Skip over navigation
STRUCTURAL ELEMENTS; BUILDING MATERIALS (for bridges E01D; specially designed for insulation or other protection E04B; elements used as building aids E04G; for mining E21; for tunnels E21D; structural elements with broader range of application than for building engineering F16, particularly F16S)
Definition statement
This subclass/group covers:

Structural elongated elements for buildings, prefabricated or not, as individual structural elements per se, e.g. pillars, columns, beams, girders, trusses;

Two-dimensional prefabricated building elements for the construction of parts of buildings, like sheets, slabs or panels, mainly for walls or partitions;

Apparatus for handling smaller elements or hardenable material for the realization of two-dimensional concrete or stone-like prefabricated elements;

Bricks or block shaped elements, but only if having special adaptations, like e.g. serving for locating conduits, or being transparent, or being built-up from parts of different materials;

Concrete reinforcements, of metal or other materials, e.g. rebars, stirrups, reinforcing grids or cages, reinforcing fibres, connectors and spacers for reinforcements

References relevant to classification in this group
This subclass/group does not cover:
Compositions of concrete, mortars or like building materials
Structural elements for bridges
Building foundations
Structural elements specially designed for insulation or other protection
Building construction in general
Load-bearing walls made from panels
Load- and non-load-bearing walls made up of layers of building elements, e.g. brick walls; bricks or block shaped building elements for walls
Other load-bearing walls
Other non-load-bearing walls; Curtain walls
Floor structures
Roof structures
Suspended or false ceilings
Roof coverings
Finishing work on building, e.g. lining, covering, flooring
Elements used as building aids, e.g. scaffolding, forms
Buildings or like structures for particular purposes, e.g. small temporary buildings, waiting shelters, telephone cabinets
Structural elements for mining
Structural elements for tunnels
Structural elements with broader range of application than for building engineering
Panels for lining or finishing
Building elements of block or other shape for the construction of parts of buildings (of relatively thin form E04C 2/00; structural elongated elements designed for load-supporting E04C 3/00, e.g. columns or pillars E04C 3/30; manufacture or material of building bricks, stones, or the like B28, C03, C04; paving elements E01C; general building constructions E04B, e.g. walls E04B 2/00, floors E04B 5/00, roofs E04B 7/00, ceilings E04B 9/00; {roof coverings E04D; coverings for walls or ceilings E04F 13/00; floorings E04F 15/00} structural elements specially designed for built-in conduit shafts E04F 17/00; {elements for buildings for particular purposes E04H 7/00} ; special elements for building ovens or furnaces F24B, F27D)
Definition statement
This subclass/group covers:

Bricks or block shaped elements for the construction of parts of buildings, but only if having special adaptations, like e.g. serving for locating conduits, or being made-up of different materials, e.g. stones with insulating inserts, or being made-up of transparent materials, e.g. glass bricks

References relevant to classification in this group
This subclass/group does not cover:
Building elements of relatively thin form, e.g. panels
Structural elongated elements designed for load-supporting, e.g. beams, column or pillars
Informative references
Attention is drawn to the following places, which may be of interest for search:
Manufacture or material of building bricks, stones, or the like
Shaping clay or other ceramic composition, producing shaped articles of clay composition
Paving elements
General building constructions
Walls
Floor structures
Roof structures
Suspended ceilings
Roof coverings
Coverings for walls or ceilings
Floorings
Structural elements specially designed for built-in conduit shafts
Elements for buildings for particular purposes
Special elements for building ovens or furnaces
Special rules of classification within this group

Building elements of block or other shape are classified in E04C 1/00 to E04C 1/42 only if they are characterised by special adaptations, if they are build-up from parts of different materials or if they are made of glass or other translucent material; general building elements of block or brick shape for walls are classified in E04B 2/00; general building elements of block or other shape for floors, e.g. filling elements, are classified in E04B 5/00.

Building elements of block or other shape characterised by particular materials, like wood, fibres or plastics are classified in P04C1/00A.

Building elements of block or other shape comprising light conducting fibres are classified in P04C1/42A.

characterised by special adaptations, e.g. serving for locating conduits, for forming soffits, cornices, or shelves, for fixing wall-plates or door-frames, for claustra
Informative references
Attention is drawn to the following places, which may be of interest for search:
Walls having cavities in the building elements
Special adaptation of floors for incorporating ducts
Soffits coverings for roof cornices
Wall copings
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Claustra
Open-work wall
{for ventilating, heating or cooling}
Definition statement
This subclass/group covers:

Building elements of block or other shape having openings or adaptations of relatively large section for ventilating, heating or cooling.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Building elements of block or other shape having openings or adaptations of relatively small section for locating conduits
Domestic or space heating systems
Air conditioning
Ventilation in general
{for claustra, fences, planting walls, e.g. sound-absorbing (pots for vertical horticulture A01G 9/022) }
References relevant to classification in this group
This subclass/group does not cover:
Pots for vertical horticulture
Informative references
Attention is drawn to the following places, which may be of interest for search:
Retaining or protecting walls, made up of similar modular elements stacked without mortar
Fences
Sound barriers
{serving for locating conduits (E04C 1/392 takes precedence) }
Definition statement
This subclass/group covers:

Building elements of block or other shape having openings or adaptations of relatively small section for locating conduits

Informative references
Attention is drawn to the following places, which may be of interest for search:
Building elements of block or other shape having openings or adaptations of relatively large section for ventilating, heating or cooling.
of glass or other transparent material { (panels made of glass bricks E04C 2/546) }
References relevant to classification in this group
This subclass/group does not cover:
Slab-like translucent elements made of glass bricks
Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels (materials or manufacture, see the relevant subclasses, e.g. B27N, D21J; made in situ E04B; specially designed for insulation or other protection E04B 1/62; load-carrying floor structures E04B 5/02, E04B 5/16; roofs consisting of self-supporting slabs E04B 7/20; roof or like covering elements E04D 3/00; for lining or finishing E04F 13/00)
Definition statement
This subclass/group covers:

Two-dimensional prefabricated building elements for the construction of parts of buildings, i.e. building elements in which one dimension is small in comparison to the other two, like e.g. sheets, slabs or panels, mainly used for walls or partitions

References relevant to classification in this group
This subclass/group does not cover:
Building elements of relatively thin form made in situ
Load-carrying floor structures, e.g. load-carrying prefabricated floor slabs
Roof or like slab shaped covering elements
Informative references
Attention is drawn to the following places, which may be of interest for search:
Manufacture by dry processes of articles, made from particles or fibres of wood
Shaping clay or other ceramic composition, producing shaped articles of clay composition
Manufacture of articles from cellulosic fibrous suspension
Building elements of relatively thin form specially designed for insulation or other protection
Roof consisting of self-supporting slabs
Slabs or panels for suspended ceilings
Building elements for lining or finishing
Special rules of classification within this group

For the materials or the manufacture, see the relevant subclasses.

Classify in E04C 2/00 to E04C 2002/3494 all additional information

characterised by specified materials (translucent E04C 2/54)
References relevant to classification in this group
This subclass/group does not cover:
Slab-like translucent elements
of concrete or other stone-like material; of asbestos cement; {of cement and other mineral fibres} (E04C 2/26 takes precedence; material or manufacture B28, C04)
References relevant to classification in this group
This subclass/group does not cover:
Building sheets, slabs or panels composed of materials covered by two or more of groups E04C 2/04, E04C 2/08, E04C 2/10, or of materials covered by one of these groups with a material not specified in one of these groups
Special rules of classification within this group

For the material or the manufacture, see B28, C04.

{Apparatus for handling the smaller elements or the hardenable material; bricklaying machines for prefabricated panels (bricklaying machines in generalE04G 21/22) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Bricklaying machines in general
{of plaster (E04C 2/049 takes precedence) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Furniture panels with a continuous layer allowing folding
Folding plates or sheets by forming folding lines and folding
Panels for suspended ceilings
Building sheets, slabs or panels made of an insulating material on plaster basis, like foamed plaster
{of concrete (E04C 2/049 takes precedence) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Walls made by projecting concrete to the exterior of an insulating foam panel
Building sheets, slabs or panels made of an insulating material on concrete basis, like cellular concrete
reinforced
Definition statement
This subclass/group covers:

Building sheets, slabs or panels made of concrete or other stone-like materials and reinforcing elements, e.g. slabs of concrete with reinforcing rods

Informative references
Attention is drawn to the following places, which may be of interest for search:
Reinforcing elements, e.g. for concrete
of metal, e.g. sheet metal (E04C 2/26 takes precedence)
References relevant to classification in this group
This subclass/group does not cover:
Building sheets, slabs or panels composed of materials covered by two or more of groups E04C 2/04, E04C 2/08, E04C 2/10, or of materials covered by one of these groups with a material not specified in one of these groups
of wood, fibres, chips, vegetable stems, or the like; of plastics; of foamed products ( {E04C 2/049} , E04C 2/26 take precedence; {hydraulic cement and mineral fibres E04C 2/04} )
References relevant to classification in this group
This subclass/group does not cover:
Building sheets, slabs or panels made of hydraulic cement and mineral fibres
Building sheets, slabs or panels made of foamed concrete or other stone-like products
Building sheets, slabs or panels composed of materials covered by two or more of groups E04C 2/04, E04C 2/08, E04C 2/10, or of materials covered by one of these groups with a material not specified in one of these groups
of solid wood
Definition statement
This subclass/group covers:

Building sheets, slabs or panels substantially made of solid wood, with or without reinforcements

References relevant to classification in this subclass/group
This subclass/group does not cover:
Building sheets, slabs or panels made of fibres, chips, vegetable stems or the like
Building sheets, slabs or panels laminated and composed of materials covered by two or more of groups E04C 2/12, E04C 2/16, E04C 2/20
Informative references
Attention is drawn to the following places, which may be of interest for search:
Wood working
Building sheets, slabs or panels laminated and composed of materials covered by two or more of groups E04C 2/12, E04C 2/16, E04C 2/20
reinforced
Informative references
Attention is drawn to the following places, which may be of interest for search:
Reinforced wooden beams
of fibres, chips, vegetable stems, or the like
Definition statement
This subclass/group covers:

Building sheets, slabs or panels composed of organic or inorganic fibres, organic or inorganic chips, vegetable stems, or the like, with or without additional glue or adhesive

References relevant to classification in this group
This subclass/group does not cover:
Building sheets, slabs or panels made of hydraulic cement and mineral fibres
Informative references
Attention is drawn to the following places, which may be of interest for search:
Building sheets, slabs or panels laminated and composed of materials covered by two or more of groups E04C 2/12, E04C 2/16, E04C 2/20
with binding wires, reinforcing bars, or the like
Informative references
Attention is drawn to the following places, which may be of interest for search:
Reinforcing elements, e.g. for concrete
of plastics
Informative references
Attention is drawn to the following places, which may be of interest for search:
Shaping of plastics
Building sheets, slabs or panels laminated and composed of materials covered by two or more of groups E04C 2/12, E04C 2/16, E04C 2/20
reinforced {E04C 2/205 takes precedence}
Definition statement
This subclass/group covers:

Building sheets, slabs or panels made of plastics and comprising reinforcing elements such as fibres, rods

Informative references
Attention is drawn to the following places, which may be of interest for search:
Building sheets, slabs or panels made of foamed plastics
Reinforcing elements, e.g. for concrete
laminated and composed of materials covered by two or more of groups E04C 2/12, E04C 2/16, E04C 2/20
Informative references
Attention is drawn to the following places, which may be of interest for search:
Layered products
composed of materials covered by two or more of groups E04C 2/04, E04C 2/08, E04C 2/10 or of materials covered by one of these groups with a material not specified in one of the groups { (of cement and mineral fibres E04C 2/04) }
Definition statement
This subclass/group covers:

Building sheets, slabs or panels, laminated or not, and composed of materials covered by two or more of groups E04C 2/04, E04C 2/08, E04C 2/10 or of materials covered by one of these groups with a material not specified in one of the groups.

References relevant to classification in this group
This subclass/group does not cover:
Building sheets, slabs or panels made of hydraulic cement and mineral fibres
Informative references
Attention is drawn to the following places, which may be of interest for search:
Layered products
composed of insulating material and concrete, stone or stone-like material
Special rules of classification within this group

Sandwich panels composed of layers of insulating material alternated with layers of concrete are classified in E04C 2/288.

composed of insulating material and non-metallic or unspecified sheet-material (E04C 2/288 takes precedence)
References relevant to classification in this group
This subclass/group does not cover:
Building sheets, slabs or panels composed of insulating material and concrete, stone or stone-like material
Informative references
Attention is drawn to the following places, which may be of interest for search:
Fibrous panels characterised by the orientation of the fibres
characterised by the shape or structure (translucent E04C 2/54)
References relevant to classification in this group
This subclass/group does not cover:
Slab-like translucent elements
formed of corrugated or otherwise indented sheet-like material; composed of such layers with or without layers of flat sheet-like material
Informative references
Attention is drawn to the following places, which may be of interest for search:
Corrugated metal floor slabs for floors
Roofing slabs having special cross-sections
Roofing slabs comprising two or more layers, with or without corrugations
Special rules of classification within this group

Corrugated sheet-like material having one as well as a plurality of layers is classified in E04C 2/32

{with parallel corrugations}
Definition statement
This subclass/group covers:

Sheet-like material with parallel corrugations, e.g. with parallel undulated corrugations

{with incisions or reliefs in the surface (E04C 2/326 takes precedence) }
References relevant to classification in this group
This subclass/group does not cover:
Building elements of relatively thin form with corrugations, incisions or reliefs in more than one direction of the element
{with corrugations, incisions or reliefs in more than one direction of the element}
Definition statement
This subclass/group covers:

Sheet-like material with corrugations, incisions or reliefs in more than one direction of the element, e.g. egg-crate reliefs

composed of two or more spaced sheet-like parts (E04C 2/32 takes precedence; spacers for cavity walls E04B 2/44)
Definition statement
This subclass/group covers:

Sheet-like elements composed of two or more spaced sheet-like parts, e.g. sandwich panels

Informative references
Attention is drawn to the following places, which may be of interest for search:
Spacers for cavity walls
Panels composed of insulating material and concrete
Building elements of relatively thin form formed of corrugated or otherwise indented sheet-material
Roofing slabs comprising two or more layers
{spaced apart by profiled spacer sheets}
Definition statement
This subclass/group covers:

Sheet-like elements composed of two or more spaced sheet-like parts, spaced apart by profiled spacer sheets, like e.g. corrugated cardboard

spaced apart by transversely-placed strip material, e.g. honeycomb panels (honeycomb or other core members for layered products B32B)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Honeycomb or other core members for layered products
with attached ribs, flanges, or the like, e.g. framed panels (concerned with attaching to other panels or elements to form a structure, see the places for the relevant structure, e.g. E04B 2/00)
Definition statement
This subclass/group covers:

Building sheets, slabs or panels having attached ribs, flanges, or the like, e.g. framed panels and panels with upstanding edges around their borders

Special rules of classification within this group

Details of connection to other panels or elements to form a structure are classified in the groups of the relevant structure, e.g. E04B 2/00 for wall structures

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Framed panel
Panel having a frame around its borders
composed of a number of smaller components rigidly or movably connected together, e.g. interlocking, hingedly connected {of particular shape, e.g. not rectangular of variable shape or size, e.g. flexible or telescopic panels (E04C 2/041 takes precedence) }
Definition statement
This subclass/group covers:

Building sheets, slabs or panels, composed of a number of smaller components rigidly or movably connected together, e.g. foldable garage doors

References relevant to classification in this group
This subclass/group does not cover:
Building sheets, slabs or panels, composed of a number of smaller components rigidly connected together, of concrete or other stone-like material, of asbestos cement, of cement and other mineral fibres
Gratings; Grid-like panels (reinforcing elements E04C 5/00; built-in gratings E04F 19/10; gratings in general F16S 3/00)
References relevant to classification in this group
This subclass/group does not cover:
Reinforcing grids or mats of metal
Grids for ceilings
Non-metallic reinforcing mats
Built-in gratings
Gratings or grilles made from a sheet
Gratings in general
Informative references
Attention is drawn to the following places, which may be of interest for search:
Grids, gratings for stable floors
Making metal grids
Circumferential gutters for swimming-pools
with special adaptations for auxiliary purposes, e.g. serving for locating conduits (E04C 2/54 takes precedence; block-shaped elements therefor E04C 1/39; floor structures incorporating ducts E04B 5/48)
References relevant to classification in this group
This subclass/group does not cover:
Slab-like translucent elements
Informative references
Attention is drawn to the following places, which may be of interest for search:
Floor structures incorporating ducts
Building elements of block shape having adaptations serving for locating conduits
{for ventilating}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Ventilation in general
{for heating or cooling (solar heat collectors F24J 2/04; heat storage F28D 20/00) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Solar heat collectors
F24J2/042
Heat storage
Slab-like translucent elements (floors for transmitting light E04B 5/46; translucent or open-work ceilings E04B 9/32, E04B 9/34; translucent roof coverings E04D 3/06, E04D 3/28)
Definition statement
This subclass/group covers:

Translucent or transparent slab-like elements

Informative references
Attention is drawn to the following places, which may be of interest for search:
Floors for transmitting light
Translucent ceilings, open work ceilings
Translucent roof coverings
{Hollow multi-walled panels with integrated webs}
Definition statement
This subclass/group covers:

Translucent hollow slab-like elements having a cross-section which is internally subdivided by walls, e.g. a translucent polyurethane roofing slab which cross section is internally subdivided by, in use, horizontal and vertical walls

Informative references
Attention is drawn to the following places, which may be of interest for search:
Translucent roof covering made with elements having special cross-sections
Extrusion dies for extruding multi-channel profiles
B29C47/20E
Greenhouse of flexible material with double or multiple walls
Structural elongated elements designed for load-supporting (as building aids E04G)
Definition statement
This subclass/group covers:

Structural elongated elements designed for permanent load-supporting in buildings, e.g. building beams and columns

References relevant to classification in this group
This subclass/group does not cover:
Structural elongated elements for bridges
Piles for foundations
Non-load supporting elongated members for partition walls
Non-load supporting elongated elements for suspended ceilings
Structural elongated elements designed as building aids
Structural elongated elements for masts, towers, poles
Structural elongated elements for tents
Structural elongated elements for mining, tunnels
Informative references
Attention is drawn to the following places, which may be of interest for search:
Structural elongated elements for railways or railway vehicles, for land vehicles, for ships, for aircrafts
Structural elongated elements for hoisting devices, e.g. cranes
Structures comprising elongated load-supporting parts; three-dimensional framework structures
Connections of bar shaped building elements; for metal bars; for wooden bars
Special rules of classification within this group

Classify in E04C 3/00 to E04C 2003/0495 all additional information

{Girders or columns that are rollable, collapsible or otherwise adjustable in length or height (girders as supporting members for forms E04G 11/54) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Structures characterised by movable, separable, or collapsible parts
Extensible girders as supporting members for forms; telescopic
Telescopic shores or struts
Telescopic poles
Collapsible frames for tents; telescopic
Telescopic grandstands; foldable, retractable tribunes
Inflatable tubular frameworks for tents
Locating rails for walls, with adjustable curvature
Extensible carriers for electric cables
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Girders or columns that are rollable
Girders or columns that are coilable or windable
Joists; Girders, trusses, or trusslike structures, e.g. prefabricated; Lintels; Transoms; {Braces} (E04C 3/38 takes precedence; for structures characterised by movable, separable, or collapsible parts E04B 1/343; {braced purlins E04B 7/024} )
References relevant to classification in this group
This subclass/group does not cover:
Arched girders or portal frames
Roof structures having braced purlins
Informative references
Attention is drawn to the following places, which may be of interest for search:
Girders for cranes
Girders for bridges
E01D9/00
Structures characterised by movable, separable, or collapsible parts
Connections of bar shaped building elements
Constructional features of the supporting construction of suspended-ceilings, e.g. inverted T-bars
Reinforcing elements consisting of light-weight girders as reinforcing elements, e.g. light-weight girders for floors construction
Girders for shutterings
Cross-sectional aspects of beams, girders and joists made of metal
Special rules of classification within this group

Structures characterised by movable, separable, or collapsible parts should be classified in E04B 1/343; when these structures have elongated structural elements presenting inventive aspects they can also be classified in E04C 3/02 or its sub-groups.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Joist
Horizontal supporting member that runs from wall to wall, wall to beam, or beam to beam to support a ceiling, a roof or a floor.
Girder
Support beam used in construction, e.g. an I-shaped girder, a box-shaped girder, a truss- or lattice-girder.
Truss
Elongated structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred as nodes.
Lintel
Load-bearing elongated element located in use over door or window openings.
Transom
A bar of wood or stone across the top of a door or window opening
Brace
A structural elongated element serving as connecting/reinforcing element between structural elements, e.g. braces between wooden joists in a floor structure
of metal (E04C 3/29 takes precedence; as reinforcing elements E04C 5/06; manufacture B21)
References relevant to classification in this group
This subclass/group does not cover:
Joists, girders or trusses built-up from parts of different material
Informative references
Attention is drawn to the following places, which may be of interest for search:
Manufacture of metallic elongated elements; Rolling of metal
Metallic girder or trusses used as reinforcing elements
Structures of metal for towers, masts or poles
Cross-sectional aspects of beams, girders and joists made of metal
Special rules of classification within this group

Metallic girders or trusses used as reinforcing elements should be classified in E04C 3/04 and its sub-groups only if they have some inventive aspects and can be used as load-supporting elements per se.

with substantially solid, i.e. unapertured, web (E04C 3/10, E04C 3/11 take precedence) {honeycomb girders E04C 3/083}
References relevant to classification in this group
This subclass/group does not cover:
Metallic joists, girders and trusses with non-parallel upper and lower edges
Honeycomb metallic beams, i.e. castellated beams; metallic beams with apertured solid web
Informative references
Attention is drawn to the following places, which may be of interest for search:
Prestressed metallic joists, girders and trusses
Cross-sectional aspects of beams, girders and joists made of metal
Special rules of classification within this group

Metallic girders having a web constituted by a series of unapertured webs having a spacing between them, i.e. like a rake, are classified in E04C 3/06 and in E04C 3/083.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
web
The "vertical" element of the beam connected to the flange(s); the beam can either be an I-, T-,C- or a box beam; in case of an H or U-beam the web is considered to be the "horizontal" element (in analogy with I- and C-beams.)
at least partly of bent or otherwise deformed strip- or sheet-like material
Definition statement
This subclass/group covers:

Metallic girders or beams having a non-apertured web and made at least partially of deformed strip- or sheet-like material, e.g. by cold rolling

Informative references
Attention is drawn to the following places, which may be of interest for search:
Bending of sheet metal
Wall partitions with framework or posts of metal
Metallic girders or beams made of bent or otherwise deformed strip- or sheet-like material, and having an apertured web
Supporting beams for a suspended ceiling having a folded cross-section
Lintels
Braces
Cross-sectional aspects of beams, girders and joists made of metal
with apertured web, e.g. with a web consisting of bar-like components; Honeycomb girders (E04C 3/10, E04C 3/11 take precedence)
References relevant to classification in this group
This subclass/group does not cover:
Metallic joists, girders and trusses with non-parallel upper and lower edges
Metallic arched girders or trusses, portal frames
Informative references
Attention is drawn to the following places, which may be of interest for search:
Truss-type bridges
Three-dimensional frameworks
Connections specially adapted for structures comprising elongated supporting parts of metal
Prestressed metallic joists, girders and trusses
Reinforcing elements consisting of metallic light-weight girders, e.g. light-weight girders for floor construction
Metallic truss-like structures for masts, towers, poles
Metallic truss-like structures composed of separate truss elements
{Honeycomb girders; Girders with apertured solid web}
Definition statement
This subclass/group covers:

Honeycomb metallic girders, i.e. castellated metallic girders; Metallic girders with apertured solid web, i.e. metallic girders in which apertures have been made in the solid web.

References relevant to classification in this group
This subclass/group does not cover:
Metallic girders or beams made of bent or otherwise deformed strip- or sheet-like material, and having an apertured web
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making rigid structural elements or units, e.g. honeycomb structures
Special rules of classification within this group

Metallic girders having a web constituted by a series of unapertured webs having a spacing between them, i.e. like a rake, are classified in E04C 3/06 and in E04C 3/083.

Synonyms and Keywords
Honeycomb girder
Castellated girder
at least partly of bent or otherwise deformed strip- or sheet-like material
Definition statement
This subclass/group covers:

Metallic girders or beams made of at least partially deformed strip- or sheet-like material, and having an apertured web, e.g. made by an expanded metal sheet or made by cutting holes in the solid web.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Supporting beams for a suspended ceiling having a folded cross-section
Wall partitions with framework or posts of metal
Metallic girders or beams made of at least partially deformed strip- or sheet-like material, and having a substantially unapertured web
Bending of sheet metal
Special rules of classification within this group

Metallic trusses made of bar-like elements consisting of bent or deformed sheet material, the bar-like elements per se having an unapertured web, should be classified in E04C 3/08 and in E04C 3/07, not in E04C 3/09.

prestressed
Informative references
Attention is drawn to the following places, which may be of interest for search:
Members specially adapted to be used in prestressed constructions
with non-parallel upper and lower edges, e.g. roof trusses (arched girders, portal frames E04C 3/38)
References relevant to classification in this group
This subclass/group does not cover:
Metallic arched girders, portal frames
Informative references
Attention is drawn to the following places, which may be of interest for search:
Connections specially adapted for structures comprising elongated supporting parts of metal
Roofs consisting of a plurality of parallel similar trusses
of wood, e.g. with reinforcements, with tensioning members (E04C 3/292 takes precedence)
References relevant to classification in this group
This subclass/group does not cover:
Joists, girders or trusses made of wood and metal
Informative references
Attention is drawn to the following places, which may be of interest for search:
Wall partitions with framework or posts of wood
Wood working
with substantially solid, i.e. unapertured, web ( {E04C 3/127,} E04C 3/17, E04C 3/18 take precedence)
References relevant to classification in this group
This subclass/group does not cover:
Joists, girders or trusses with non-parallel upper and lower edges, e.g. roof trusses
Joists, girders or trusses made of wood with metal or other reinforcements or tensioning members
Special rules of classification within this group

Wooden girders having a web constituted by a series of unapertured webs having a spacing between them, i.e. like a rake, are classified in E04C 3/14 and in E04C 3/16.

with apertured web, e.g. trusses (E04C 3/17, E04C 3/18 take precedence)
References relevant to classification in this group
This subclass/group does not cover:
Joists, girders, or trusses with non-parallel upper and lower edges, e.g. roof trusses
Wooden arched girders, portal frames
Informative references
Attention is drawn to the following places, which may be of interest for search:
Three-dimensional framework structures
Connections specially adapted for structures comprising elongated supporting parts of wood
Joists, girders or trusses made of wood with metal or other reinforcements or tensioning members
Wooden truss-like structures for masts, towers and poles
Special rules of classification within this group

Wooden girders having a web constituted by a series of unapertured webs having a spacing between them, i.e. like a rake, are classified in E04C 3/14 and in E04C 3/16.

with non-parallel upper and lower edges, e.g. roof trusses
References relevant to classification in this group
This subclass/group does not cover:
Wooden arched girders, portal frames
Informative references
Attention is drawn to the following places, which may be of interest for search:
Connections specially adapted for structures comprising elongated supporting parts of wood
Roof consisting of a plurality of parallel similar trusses
Wood working
with metal {or other} reinforcements or tensioning members
Informative references
Attention is drawn to the following places, which may be of interest for search:
Reinforced panels of solid wood
Joists, girders or trusses made of wood and metal
Members specially adapted to be used in prestressed constructions
{Synthetic reinforcements}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Reinforcing elements of material other than metal
of concrete or other stone-like material, e.g. with reinforcements or tensioning members (reinforcing elements E04C 5/00)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Joists, girders or trusses built-up from parts of steel and parts of concrete
Reinforcing elements
{with apertured web, e.g. frameworks, trusses (E04C 3/26 takes precedence) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Prestressed joints, girders or trusses made of concrete or other stone-like material
built-up by elements jointed in line
Definition statement
This subclass/group covers:

Concrete beams built-up by elements jointed in-line, e.g. made up of stacked elements

Informative references
Attention is drawn to the following places, which may be of interest for search:
Prestressed joints, girders or trusses made of concrete or other stone-like material
prestressed (E04C 3/22, E04C 3/29 take precedence; Prestressing members E04C 5/08)
References relevant to classification in this group
This subclass/group does not cover:
Joists, girders or trusses made of concrete or other stone-like material, and built-up by elements jointed in line
Informative references
Attention is drawn to the following places, which may be of interest for search:
Joists, girders or trusses built-up from parts of steel and parts of concrete
Members specially adapted to be used in prestressed constructions
of other materials not covered by groups E04C 3/40 - E04C 3/44
Definition statement
This subclass/group covers:

Joists, girders or trusses made of specified materials other than metal, wood. concrete or stone-like materials, e.g. joists made of glass or plastics

References relevant to classification in this group
This subclass/group does not cover:
Joists, girders or trusses built-up from parts of different materials, e.g. laminated from parts of different materials
Informative references
Attention is drawn to the following places, which may be of interest for search:
Producing beams of plastics
built-up from parts of different material, {i.e. composite structures}
Definition statement
This subclass/group covers:

Joists, girders or trusses built-up from parts of specified different materials, e.g. built-up from laminated parts of different materials, or from assembled parts of different materials

Informative references
Attention is drawn to the following places, which may be of interest for search:
Shaping composites
Producing beams of plastics
Layered products
Superstructures of vehicles characterised by the materials
Special rules of classification within this subclass/group

Wooden or concrete beams having reinforcements should primarily be classified in E04C 3/18, E04C 3/185 respectively E04C 3/20-E04C 3/26; when the reinforcements represent a substantial part of the cross-section of the beam, or are themselves constituting a beam, the composite wooden or concrete beams with these reinforcing elements can also be classified in E04C 3/29

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Composite structure
Composite structure refers to the structure of the assembly of the different parts, not to the material
the materials being wood and metal
References relevant to classification in this group
This subclass/group does not cover:
Wooden joists, girders or trusses with metal reinforcements or tensioning members
the materials being steel and concrete (concrete with internal reinforcements or tensioning members E04C 3/20)
References relevant to classification in this group
This subclass/group does not cover:
Metallic beams forming part of a floor structure
Joists, girders or trusses made of concrete with internal reinforcements or tensioning members
of concrete combined with a girder-like structure extending laterally outside the element (light weight girders used as reinforcement E04C 5/065; as part of a floor structure E04B 5/23)
Definition statement
This subclass/group covers:

Girders or trusses built-up from a concrete element and a steel girder-like structure extending laterally outside the concrete element

References relevant to classification in this group
This subclass/group does not cover:
Metallic beams forming part of a floor structure, and extending below the floor
Light weight girders with concrete precast parts, used as reinforcement
Columns; Pillars; Struts (not designed for end loading E04C 3/02; posts, masts, as independent structures E04H 12/00)
References relevant to classification in this group
This subclass/group does not cover:
Elongated supporting members for partition walls
Structural elongated elements not designed for end loading
Structural elongated elements designed as building aids
Posts, masts as independent structures
Structural elongated elements for tents
Poles for tents
Informative references
Attention is drawn to the following places, which may be of interest for search:
Coverings or linings for columns
of metal (E04C 3/36 takes precedence)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Girders made of metal
Cross-sectional aspects of beams, girders and joists made of metal
Special rules of classification within this group

Always classify in E04C 3/32 columns or pillars in which at least a bearing part of the column or pillar is made of metal, with the exception of concrete rebars

of concrete other stone-like material, with or without permanent form elements, with or without internal or external reinforcement, e.g. metal coverings (E04C 3/36 takes precedence)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Closed reinforcement cages composed of one single bent reinforcement mat
Closed reinforcement cages with spiral- or coil-shaped stirrup rod
Special rules of classification within this group

Always classify in E04C 3/34 columns or pillars in which at least a bearing part of the column or pillar is made of concrete or stone-like material

of other materials not covered by groups E04C 3/40 - E04C 3/44; of a combination of two or more materials
Definition statement
This subclass/group covers:

Columns, pillars or struts made of specified materials other than metal or concrete or stone-like materials, e.g. wood, glass, plastics

Informative references
Attention is drawn to the following places, which may be of interest for search:
Joists, girders or trusses made of materials other than metal, wood. concrete or stone-like materials, e.g. joists made of glass or plastics
Joists, girders or trusses built-up from parts of different materials, e.g. laminated from parts of different materials
Arched girders or portal frames (straight girders able to be bent E04C 3/02; inflatable E04H 15/20)
References relevant to classification in this group
This subclass/group does not cover:
Straight girders able to be bent
Inflatable girders or portal frames
Informative references
Attention is drawn to the following places, which may be of interest for search:
Gantries or semi-gantries, a.k.a. road sign holders
Arched structures
Vaulted roofs
Arched-type supports for tents
of metal (E04C 3/46 takes precedence)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Mechanical metal-working
Metallic girders
Metallic trusses
Cross-sectional aspects of beams, girders and joists made of metal
Connections specially adapted for structures comprising elongated supporting parts of metal
Special rules of classification within this group

Always classify in E04C 3/40 if a bearing part of the arched girder or portal frame is made of metal

of wood, e.g. units for rafter roofs (E04C 3/46 takes precedence)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Working of wood
Connections specially adapted for structures comprising elongated supporting parts of wood
Wooden girders
Wooden trusses
Special rules of classification within this group

Always classify in E04C 3/42 if a bearing part of the arched girder or portal frame is made of wood

of concrete or other stone-like material, e.g. with reinforcements or tensioning members (E04C 3/46 takes precedence)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Reinforcing elements
Special rules of classification within this group

Always classify in E04C 3/44 if a bearing part of the arched girder or portal frame is made of concrete or other stone-like material

of other materials not covered by groups E04C 3/40 - E04C 3/44; of a combination of two or more materials
Definition statement
This subclass/group covers:

Arched girders or portal frames made of specified materials other than metal, wood, concrete or stone-like material, e.g. of glass, plastics

Informative references
Attention is drawn to the following places, which may be of interest for search:
Joists, girders or trusses made of materials other than metal, wood. concrete or stone-like materials, e.g. joists made of glass or plastics
Joists, girders or trusses built-up from parts of different materials, e.g. laminated from parts of different materials
Reinforcing elements, e.g. for concrete; Auxiliary elements therefor ( {methods or devices for making reinforcing materials B21D} ; material composition {C04B} , C21, C22; arrangements of reinforcing elements, see the relevant subclasses)
Definition statement
This subclass/group covers:

Reinforcing elements, metallic and non-metallic, in particular for concrete;

Auxiliary elements for reinforcements, e.g. connectors, spacers;

Arrangements of reinforcing elements, e.g. stirrup baskets

References relevant to classification in this group
This subclass/group does not cover:
Methods or devices for making metallic reinforcing materials
Informative references
Attention is drawn to the following places, which may be of interest for search:
Material composition
Reinforcing elements of metal, e.g. with non-structural coatings { (E04C 5/08 takes precedence) }
References relevant to classification in this group
This subclass/group does not cover:
Members specially adapted to be used in prestressed constructions
Informative references
Attention is drawn to the following places, which may be of interest for search:
Mechanical metal-working
Working or processing of metallic wire
{Discrete reinforcing elements, e.g. fibres}
Definition statement
This subclass/group covers:

Discrete reinforcing elements of metal, i.e. suitable to be mixed with the concrete before pouring, e.g. metal fibres

Informative references
Attention is drawn to the following places, which may be of interest for search:
Filler material of fibre shape for concrete
Special rules of classification within this group

Discrete reinforcing elements of metal with a well-defined shape other than granular are classified in E04C1/00A; discrete elements of metal of granular shape or the shape of which is not defined are considered filler elements and are only classified in C04B

{Anti-corrosion coatings or treating compositions, e.g. containing waterglass or based on another metal (coating of discrete reinforcing elements C04B 20/10) }
Definition statement
This subclass/group covers:

Reinforcing elements of metal including anti-corrosion coatings or treating compositions or in-situ anti-corrosion treatments, e.g. cathodic protection

References relevant to classification in this group
This subclass/group does not cover:
Coating of discrete metallic reinforcing elements, e.g. coating of metallic fibres
Informative references
Attention is drawn to the following places, which may be of interest for search:
Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger
{Anti-corrosion coatings or treating compositions containing cement}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Mortars containing hydraulic cement
Coating compositions based on cement
of low bending resistance
References relevant to classification in this group
This subclass/group does not cover:
Anchoring devices specially adapted for balconies
Informative references
Attention is drawn to the following places, which may be of interest for search:
Masonry wall-ties, e.g. anchors
Reinforcing elements for brick walls, inserted between brick layers
with indentations, projections, ribs, or the like, for augmenting the adherence to the concrete
Informative references
Attention is drawn to the following places, which may be of interest for search:
Rolling or cold-forming of concrete metallic reinforcement bars
Bending of reinforcing metallic rods for concrete
Mats ( {combined with reinforcing elements protruding out of the plane of the mat E04C 5/0627; three-dimensional mats E04C 5/0636} ; bases for plaster E04F 13/04)
Definition statement
This subclass/group covers:

Metallic reinforcing mats

References relevant to classification in this group
This subclass/group does not cover:
Metallic reinforcing mats combined with reinforcing elements protruding out of the plane of the mat
Three-dimensional metallic reinforcing mats
Bases for plaster
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making metallic wire nets
of high bending resistance, i.e. of essentially three-dimensional extent, e.g. lattice girders { (anchorage devices specially adapted for balconies E04B 1/0038; supporting devices for connector reinforcing rods for concrete walls E04G 21/125) }
References relevant to classification in this group
This subclass/group does not cover:
Anchorage devices specially adapted for balconies
Supporting devices for connector reinforcing rods for concrete walls, e.g. reinforcement connection boxes
Special rules of classification within this group

Loose closed stirrups suitable to make prismatic or cylindrical reinforcement cages are classified in E04C 5/0604.

Loose open stirrups suitable to make stirrup baskets are classified in E04C 5/0622.

{Prismatic or cylindrical reinforcement cages composed of longitudinal bars and open or closed stirrup rods (E04C 5/0631 takes precedence) }
References relevant to classification in this group
This subclass/group does not cover:
Reinforcing mats combined with separate prefabricated reinforcement cages or girders
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making wire network of tubular form, e.g. as reinforcement for pipes or pillars
Making wire network of tubular form by attaching individual stirrups to longitudinal wires
Special rules of classification within this group

Loose closed stirrups suitable to make prismatic or cylindrical reinforcement cages are classified in E04C 5/0604.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
open stirrup rod
Rebar bent in an open loop
closed stirrup rod
Rebar bent in a closed loop
{Closed cages composed of two or more coacting cage parts, e.g. transversally hinged or nested parts}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making wire network of tubular form by bending preformed mesh
{Closed cages made of one single bent reinforcement mat}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making wire network of tubular form by bending preformed mesh
{Closed cages with spiral- or coil-shaped stirrup rod}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making wire network of tubular form by attaching continuous stirrup to longitudinal wires, by rotation
Prefabricated foundation piles of reinforced concrete
Concrete foundation piles cast in situ
Columns or pillars made of concrete
{Open cages, e.g. connecting stirrup baskets (E04C 5/0609 takes precedence) }
References relevant to classification in this group
This subclass/group does not cover:
Closed cages composed of two or more co-acting cage parts
Special rules of classification within this group

Loose stirrups suitable to make stirrup baskets are classified in E04C 5/0622.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
stirrup basket
a substantially U-shaped channel like basket made of a series of parallel open stirrups positioned one after the other and linked by at least one longitudinal rebar
{Three-dimensional reinforcements composed of a prefabricated reinforcing mat combined with reinforcing elements protruding out of the plane of the mat (E04C 5/0645 takes precedence) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Shear reinforcements
Making of plaster-carrying wire network
{Reinforcing mats combined with separate prefabricated reinforcement cages or girders (E04C 5/064 takes precedence) }
References relevant to classification in this group
This subclass/group does not cover:
Three-dimensional reinforcing mats composed of two parallel mats connected by separate connecting parts
Special rules of classification within this group

E04C 5/064 takes precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
girder
a light-weight metallic girder that can also be used as concrete reinforcement
{Three-dimensional reinforcing mats composed of reinforcing elements laying in two or more parallel planes and connected by separate reinforcing parts (E04C 5/0645 takes precedence) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Shear reinforcements
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
separate reinforcing parts
parts that are not connected to the reinforcing elements before being connected to them
{the reinforcing elements in each plane being formed by, or forming a, mat of longitunal and transverse bars}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making wire networks of three-dimensional form by connecting wire networks
{Shear reinforcements, e.g. shearheads for floor slabs}
Definition statement
This subclass/group covers:

Metallic reinforcements specially adapted for shear reinforcement, e.g. shearheads for floor slabs, shear baskets, shear spiral reinforcements, shear studs,

Informative references
Attention is drawn to the following places, which may be of interest for search:
Floor structures of extraordinary design
Light-weight girders, e.g. with precast parts (light-weight girders in general E04C 3/08, E04C 3/294)
Definition statement
This subclass/group covers:

Light-weight girders, e.g. with precast concrete, like the pre-fabricated light-weight girders for floor construction

Informative references
Attention is drawn to the following places, which may be of interest for search:
Metallic girders with apertured web
Girders made of concrete combined with a girder-like structure extending laterally outside the element
Reinforcing elements of material other than metal, e.g. of glass, of plastics, or not exclusively made of metal (metal elements with non-structural coatings E04C 5/01)
References relevant to classification in this group
This subclass/group does not cover:
Anchoring devices specially adapted for balconies
Metal elements with non-structural coatings
Informative references
Attention is drawn to the following places, which may be of interest for search:
Reinforcing elements for brick walls, inserted between brick layers
Increasing or restoring the load-bearing capacity of building construction elements
{Discrete reinforcing elements, e.g. fibres}
Definition statement
This subclass/group covers:

Non entirely metallic discrete reinforcing elements, i.e. suitable to be mixed with the concrete before pouring, e.g. glass or carbon fibres

Informative references
Attention is drawn to the following places, which may be of interest for search:
Filler material of fibre shape for concrete
Special rules of classification within this group

Non entirely metallic discrete reinforcing elements with a well-defined shape other than granular are classified in E04C7/00A; non entirely metallic discrete elements of granular shape or the shape of which is not defined are considered filler elements and are only classified in C04B

Members specially adapted to be used in prestressed constructions { (production of reinforced objects in general B28B 23/00; prestressed structures produced in situ E04G 21/12) }
Definition statement
This subclass/group covers:

Members specially adapted to be used in prestressed constructions, e.g. prestressing tendons and cables, ducts, anchoring devices.

References relevant to classification in this group
This subclass/group does not cover:
Tools or methods for in situ tensioning
Tensioning of moulded or shaped articles, at the factory
Informative references
Attention is drawn to the following places, which may be of interest for search:
Anchors; Connections of cables to bridge parts
Suspension cables for bridges
Increasing or restoring the load-bearing capacity of building construction elements
Ducts
Informative references
Attention is drawn to the following places, which may be of interest for search:
Rigid pipes wound from sheets or strips of metal
Anchoring devices (tools or methods for tensioning {in situ} E04G 21/12)
References relevant to classification in this group
This subclass/group does not cover:
Tools or methods for tensioning in situ
{the tensile members are anchored by wedge-action}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Construction of stressing jacks
{the tensile members are profiled to ensure the anchorage, e.g. when provided with screw-thread, bulges, corrugations}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making helical shapes on metallic bodies
Ground anchors
Coaxial connection of reinforcement bars by means of sleeves
Anchoring bolts for galleries
Auxiliary parts for reinforcements, e.g. connectors, spacers, stirrups ( {E04C 5/06 takes precedence;} tools connecting reinforcing elements E04G 21/12)
Definition statement
This subclass/group covers:

Auxiliary parts for reinforcements, e.g. connectors and spacers

References relevant to classification in this group
This subclass/group does not cover:
Tools for connecting reinforcing elements
Supporting devices for connector reinforcing rods for concrete walls, e.g. reinforcement connection boxes
Informative references
Attention is drawn to the following places, which may be of interest for search:
Connecting stirrup baskets
Special rules of classification within this group

Loose closed stirrups suitable to make prismatic or cylindrical reinforcement cages are classified in E04C 5/0604.

Loose open stirrups suitable to make stirrup baskets are classified in E04C 5/0622.

{Connectors or means for connecting parts for reinforcements (E04C 5/168 takes precedence) }
References relevant to classification in this group
This subclass/group does not cover:
Machines for joining reinforcing bars
Informative references
Attention is drawn to the following places, which may be of interest for search:
Spacers connecting parts for reinforcement and spacing the reinforcements from the form
{the reinforcements running in one single direction}
Definition statement
This subclass/group covers:

Connectors connecting reinforcements running in one single direction, either coaxially or only parallel to one another

{Coaxial connection by means of sleeves}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Connections wire to wire by soldering or welding with additional connecting elements or material
Making helical shapes on metallic bodies
Connections using screw-thread elements for coaxial connections of two rods
{the reinforcements running in different directions}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Machines for joining reinforcing bars
{Connection by means of clips or other resilient elements}
Definition statement
This subclass/group covers:

Connection by means of clips or other resilient material of reinforcements running in different directions

Informative references
Attention is drawn to the following places, which may be of interest for search:
Clamping or clipping connections for rods forming a crossed-over connection
{Spacers connecting parts for reinforcements and spacing the reinforcements from the form}
Definition statement
This subclass/group covers:

Spacers connecting parts for reinforcement together, and spacing the reinforcements from the form

Informative references
Attention is drawn to the following places, which may be of interest for search:
Substantially metallic spacers
Non substantially metallic spacers
{ Spacers} of metal or substantially of metal { (E04C 5/168 takes precedence) }
Definition statement
This subclass/group covers:

Metallic or substantially metallic spacers spacing the reinforcements from the form or spacing the reinforcements from one another, e.g. spacers between two reinforcing grids (upper and lower) in a floor structure

References relevant to classification in this group
This subclass/group does not cover:
Spacers connecting parts for reinforcements and spacing the reinforcements from the form
of material other than metal or with only additional metal parts, e.g. concrete or plastics spacers with metal binding wires { (E04C 5/168 takes precedence) }
Definition statement
This subclass/group covers:

Spacers of material other than metal or with only additional metal parts, e.g. concrete or plastics spacers with metal binding wires, spacing the reinforcements from the form or spacing the reinforcements from one another, e.g. spacers between two reinforcing grids (upper and lower) in a floor structure

References relevant to classification in this group
This subclass/group does not cover:
Spacers connecting parts for reinforcements and spacing the reinforcements from the form
This page is owned by Office of Patent Classification.
Last Modified: 10/11/2013