Structural and base materials

Masonry & Block Materials

Masonry is built from units and the mortar between them, which means the wall is a system rather than a material. Two walls built from identical bricks can behave very differently depending on the mortar, the cavity, the ties, the openings and the way water is managed at the top and bottom of the wall.

These entries describe the units and components themselves — what they are, where they are commonly met and what their performance depends on. Wall build-ups, structural adequacy, cavity detailing and movement provision are design matters for qualified professionals.

19 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.

Clay and concrete masonry units, including lightweight and reclaimed units
Mortars and the accessories that make masonry work as an assembly
Stone and gabion walling units used in construction and landscape
Not covered: wall design, structural adequacy, movement-joint spacing or cavity detailing

Start here

Frequently referenced entries

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

Clay facing brick →Fired clay units chosen mainly for the look of the finished wall face, bedded in mortar and used where the brickwork itself is the visible external surface.Concrete block →Cast concrete masonry units, solid or hollow, used for inner leaves, partitions, substructure and retaining work where a dense and heavy unit is wanted.Masonry mortar →The bedding and jointing material that binds masonry units into a wall, and the component that usually decides how the finished wall moves, weathers and fails.

All entries

Every masonry & blocks entry

The complete set for this category, in reference order.

Entry describes

Role in an assembly

Part of a building

Clay facing brick →Fired clay units chosen mainly for the look of the finished wall face, bedded in mortar and used where the brickwork itself is the visible external surface.

Engineering brick →Dense fired clay units turned to where low water absorption governs, such as below damp-proof course level, in retaining work and in the more exposed masonry details.

Concrete block →Cast concrete masonry units, solid or hollow, used for inner leaves, partitions, substructure and retaining work where a dense and heavy unit is wanted.

Aerated concrete block →Lightweight air-entrained masonry units with a closed cellular structure, easy to cut and handle, but very different from dense blocks in how they accept fixings.

Reclaimed brick →Bricks recovered from demolition and cleaned for reuse, valued for weathered character but variable in size, hardness, absorption and the mortar they were bedded in.

Brick slips →Thin facing slices of brick applied to a backing as a cladding, giving the look of brickwork without being structural masonry in their own right.

Masonry mortar →The bedding and jointing material that binds masonry units into a wall, and the component that usually decides how the finished wall moves, weathers and fails.

Wall ties →Metal components that connect the leaves of a cavity wall or restrain masonry to a frame, with type and arrangement set as an engineering decision rather than a material choice.

Masonry lintels →Components that carry masonry and other loads across an opening, supplied in steel, precast or prestressed concrete forms, and sized as an engineering decision.

Clay blocks →Large fired clay masonry units with internal voids, laid as walling in place of concrete blocks and distinguished from brick by their size and hollow structure.

Dressed stone blocks →Natural stone quarried and worked to squared faces and beds, laid as masonry with fine or coarse joints depending on how far the stone has been dressed.

Gabion walling →Wire mesh cages filled with stone and stacked to form walls, used mostly in external works and landscape for retaining, boundaries and free-draining structures.

Bed-joint reinforcement →Prefabricated metal reinforcement bedded along masonry joints in the plane of a leaf, running with the wall rather than across the cavity as a tie does.

Building lime →The lime binder itself rather than a product made from it: air lime, natural hydraulic lime and hydrated lime set by different mechanisms on different timescales.

Clay flue liner →Fired clay sections with a socketed end, built one on another as the continuous inner lining of a masonry chimney, forming the surface the flue gases meet.

Compressed earth block →Masonry units pressed from prepared subsoil and cured by drying rather than firing, sometimes stabilised with a little lime or cement, and laid in an earth or lime mortar.

Geogrid →A polymer grid laid in layers within compacted fill so that grid and fill act together as one mass, taking tension the soil itself cannot carry.

Airbricks and ventilators →Manufactured units that form a deliberate ventilation opening through a wall, from clay and concrete airbricks to grille ventilators and telescopic ducts.

Calcium silicate brick →Masonry units pressed from sand or crushed flint with lime and cured under steam pressure, a lime-bound brick that is neither fired clay nor cement-based.

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.

Thermal layer

Materials whose role in the build-up is thermal.

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.

Internal surface

The visible inner face people see, touch and walk on.

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 · 8
Structural frame · 5
External walls · 17
Roofs · 1
Internal walls and ceilings · 14
Floors · 1
External works and landscape · 9

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.

Exterior materials guides →Planning guidance for external walls and facades.Construction guides →How masonry and envelope stages are planned.Building envelope checklists →Preparation before envelope conversations.

Building Systems Encyclopedia

The assemblies these materials sit in

A material page explains what a substance is. These pages explain how the assembly around it is organised, what roles its components perform and which interfaces matter.

Structure and supportPrimary Structural Frames and Load-Bearing Wall Systems →Complete primary load paths from roof to foundation in masonry, timber, steel and concrete, together with the stability system without which none of them stands up.Building envelopeExternal Wall Build-Up Systems →Complete external walls read as a layer order: where in the thickness of the wall water is stopped, and in which direction the wall is allowed to dry afterwards.

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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