Structural and base materials

Aggregates & Groundworks Materials

Most of a building's ground construction is not bound. It is crushed rock, sand, recycled aggregate and geosynthetic sheet, compacted in layers, and its behaviour comes from grading, compaction and drainage rather than from a chemical set. That is why it sits apart from the cement-based family: nothing here cures.

These entries describe what each material is and what its behaviour depends on. They state no grading envelope, layer thickness, compaction requirement, permeability or bearing value — those are ground-engineering determinations made from site investigation, and they belong with the qualified professionals responsible for the work.

8 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.

Unbound granular materials: crushed rock, sands, gravels and recycled aggregates
Geosynthetics laid in ground construction: separation, filtration and reinforcement sheet
Drainage media and the cellular and confinement products laid within ground build-ups
Buried drainage goods: the pipes, fittings and chamber components laid in ground construction
Bituminous bound surfacing materials laid over a granular foundation
Does not cover cement-based materials, which are published under concrete and cement
Does not cover the POSITIONS these materials fill — a sub-base layer, a capping layer, engineered fill and a filter separation layer are published components
Does not cover ground construction as an arrangement — pavement foundations, drainage and retaining works are published building systems

All entries

Every aggregates & groundworks entry

The complete set for this category, in reference order.

Entry describes

Role in an assembly

Part of a building

Geocell →A collapsible polymer honeycomb expanded on site and filled, so that each pocket of granular, soil or concrete infill is walled against spreading sideways under load.

Concrete aggregate →The graded stone and sand that makes up most of a concrete or mortar mix by volume, where grading, shape, cleanliness and absorption decide how the mix behaves.

Crushed rock and unbound fill →Crushed rock, gravel, sand and recycled aggregate placed and compacted without any binder, where grading, compaction and drainage rather than a chemical set govern how it behaves.

Attenuation crate →A stacked modular polymer box that creates and holds open a storage void below ground, wrapped in permeable or impermeable geotextile depending on where the water is meant to go.

Geotextile separation fabric →A deliberately permeable engineered fabric laid between two different materials so that water passes through it while fine particles are kept out of the coarse layer.

Non-woven geotextile →A lofted mat of randomly laid fibres bonded by needling or heat, which cushions and drains within its own thickness as well as separating the layers it lies between.

Polymer concrete →Graded mineral aggregate bound in a thermosetting resin rather than cement — concrete in name and appearance only, cured by chemical reaction in a mould.

PVC-U drainage pipe →Extruded and moulded unplasticised PVC pipe, bends, junctions, gullies and chamber components, jointed either by solvent welding or by push-fit ring seals — two methods that do not mix.

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.

Structure

Materials that carry load or form the primary frame.

Substrate and base

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

Moisture and air control

Thin layers that control where moisture and air are allowed to move.

External surface

The visible outer face of a wall or roof.

Polymer concrete →

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 · 8
Structural frame · 1
External walls · 1
Roofs · 1
Floors · 3
Wet areas · 1
External works and landscape · 8

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.

Construction guides →How groundwork and substructure stages are planned.Landscape design guides →Where paving, drainage and external levels are decided.Materials planning guides →The planning and comparison side of the same subject.

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 →

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