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Structural and base materials

Metals in Construction

Metals turn up throughout a building: as frame, as reinforcement, as sheet roofing and cladding, as lath and mesh, and as the fixings that hold other materials in place. The questions that matter are usually about corrosion, compatibility and movement rather than raw strength.

Two themes recur. Different metals in contact, in the presence of moisture, can corrode faster than either would alone. And metals move measurably with temperature, which is why sheet metal roofing and cladding are detailed with movement in mind. Both are design matters for qualified professionals.

12 reference entries · educational materials reference · suitability always depends on the complete assembly and qualified professional review

Scope

What this category covers

Where the boundary of this part of the library sits, including what it deliberately leaves to qualified professionals.

  • Structural and light-gauge steel, reinforcement and decking
  • Corrosion-protected and corrosion-resistant metals used in the envelope
  • Non-ferrous sheet metals used for roofing, cladding and flashings
  • Not covered: structural sizing, connection design, corrosion-protection specification

Start here

Frequently referenced entries

A starting point, not a ranking — these are simply the entries most people arrive looking for.

All entries

Every metals entry

The complete set for this category, in reference order.

Structural steelHot-rolled steel beams, columns and hollow sections used for primary structure, fabricated off site and connected on site by bolting or welding.Light gauge steel framingCold-formed steel studs, tracks and joists roll-formed from thin coated coil, used for framing, infill walls and light structure rather than for primary beams.Galvanised steelSteel carrying a metallic zinc coating that corrodes in preference to the steel beneath it, which makes cut edges, drilled holes and site damage the real subject.Stainless steelSteel alloyed with chromium so that a thin passive surface film resists corrosion through the metal's own chemistry rather than through any coating applied to it.AluminiumA light metal used as rolled sheet, extruded profiles and castings, carrying its own oxide film and usually finished further by anodising or by powder coating.Copper sheetRolled copper used as fully supported roofing, cladding and flashing, worked by folding and seaming, and changing colour steadily as a patina develops outdoors.Zinc sheetRolled zinc alloyed with small additions of titanium and copper, used as fully supported roofing and cladding and settling to a matt grey surface layer outdoors.Weathering steelLow-alloy steel that forms a dense, adherent rust layer through repeated wetting and drying, used unpainted where its orange-brown surface is part of the design.Steel reinforcing barRibbed steel bar cast into concrete to carry tensile forces, protected from corrosion by the alkaline environment of the sound concrete cover surrounding it.Profiled metal deckingCold-formed profiled steel sheet spanning between supports as permanent formwork to a concrete floor, or as a structural roof deck carrying the build-up above it.Metal lathExpanded or perforated metal sheet fixed as a background for render and plaster, giving a mechanical key where the wall behind cannot provide one of its own.Lead sheetA dense, highly workable sheet metal traditionally used for flashings, valleys and weatherings, dressed to shape by trained trades who manage its handling considerations.

Browse by role

By the role the material plays

The same entries, clustered by what they typically do in an assembly. A material can appear in more than one cluster because it genuinely plays more than one role.

Substrate and base

Backgrounds and bases that other materials are fixed or applied to.

Weather barrier

Layers that shed or resist rain, wind and weather.

Jointing and fixing

Materials that bond, seal, support or connect other materials.

Where they appear

Parts of a building this category touches

An orientation aid only — it does not imply that any entry is suitable for that part of a particular building.

  • Foundations and groundworks · 1
  • Structural frame · 7
  • External walls · 9
  • Roofs · 8
  • Internal walls and ceilings · 3
  • Floors · 4
  • Wet areas · 1
  • External works and landscape · 4

Elsewhere on Build Design Hub

Planning guidance for this subject

This library explains what materials are. These sections help with choosing between them and preparing for the conversation.

Materials & Systems Encyclopedia

Reference entries for building materials, product formats and system components — what they are, what their behaviour depends on and what to ask about them.

Browse the full Materials Library →