Envelope and protection

Roofing Materials & Systems

A roof is a system, not a covering. The visible material sits above underlays, battens or decks, insulation, ventilation paths and a whole set of junctions at eaves, verges, ridges, valleys, upstands and penetrations. Most roof problems begin at those junctions rather than in the middle of the covering.

These entries describe the coverings and membranes themselves. They do not contain falls, drainage design, fixing patterns, wind-uplift assessments or waterproofing specifications, and no entry claims that any covering is watertight on its own — watertightness is a property of the completed, correctly detailed and correctly installed roof.

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.

Pitched-roof coverings: clay and concrete tiles, slate, shingles, thatch
Sheet-metal roofing and profiled sheeting
Flat-roof waterproofing: single-ply, built-up, liquid-applied and green-roof build-ups
Not covered: falls and drainage design, fixing patterns, wind-uplift or waterproofing specification

Start here

Frequently referenced entries

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

Natural slate roofing →Natural slate is a quarried metamorphic rock split into thin sheets and laid in courses, and this entry separates the stone itself from the manufactured boards that imitate its format.Standing seam metal roof →Standing seam roofing joins long metal trays by folding their upstands together, using concealed clips that let the metal move, which sets it apart from through-fixed profiled sheeting.EPDM roofing membrane →EPDM is a cured synthetic rubber laid as a single ply, often in sheets large enough to cover a small roof in one piece, with any seams bonded by adhesive or tape rather than heat.

All entries

Every roofing entry

The complete set for this category, in reference order.

Entry describes

Role in an assembly

Part of a building

Clay roof tiles →Fired clay roof tiles are discrete units hung in courses over battens, and this entry sets out how they differ from cast concrete tiles and why the roof system around them decides the outcome.

Concrete roof tiles →Concrete roof tiles are cast and cured rather than fired, and this entry covers how their surface colour, their weight and their weathering differ from clay tiles of similar profile.

Fibre cement slate →Fibre cement slate is a pressed board of cement and reinforcing fibres cut to a slate format, and this entry sets out how it differs from quarried stone in look, ageing and repair.

Asphalt shingles →Asphalt shingles are flexible bitumen strips surfaced with mineral granules and laid in courses over a continuous deck, which makes them quite unlike discrete tiles hung on battens.

Thatch roofing →Thatch is a roof covering of bundled plant stems laid in courses, and it comes with its own craft, its own maintenance rhythm and its own conversations with insurers and local authorities.

Standing seam metal roof →Standing seam roofing joins long metal trays by folding their upstands together, using concealed clips that let the metal move, which sets it apart from through-fixed profiled sheeting.

Profiled metal sheeting →Profiled metal sheets are rolled into corrugations or ribs and fixed through their face into the supports below, which makes the fasteners and their washers part of the weather line.

Built-up felt roofing →Built-up felt roofing is formed in place from several bonded bituminous layers rather than a single sheet, so its redundancy comes from the layers and from how each is dressed at junctions.

EPDM roofing membrane →EPDM is a cured synthetic rubber laid as a single ply, often in sheets large enough to cover a small roof in one piece, with any seams bonded by adhesive or tape rather than heat.

TPO roofing membrane →TPO is a thermoplastic single-ply sheet whose seams are fused with hot air rather than bonded with adhesive, a genuinely different jointing mechanism calling for different equipment and skills.

Liquid applied roof coating →Applied wet and cured in place, a liquid system forms a continuous film with no seams, which is why it suits complicated roofs and why preparation and film continuity decide the result.

Green roof system →A green roof is a planted build-up sitting above a roof's waterproofing layer, so the real subjects are the layers beneath it, access for inspection, the outlets and the added load.

Roofing underlay →Roofing underlay is the secondary layer beneath a covering, and the distinction between vapour-permeable and impermeable types drives how the roof space below has to be ventilated.

Corrugated fibre cement sheet →A large profiled cement-and-fibre sheet that spans between purlins and is the roof covering itself, carried by its own corrugations rather than by a deck beneath it.

Mastic asphalt roofing →Mastic asphalt laid hot in successive coats over an isolating layer, forming a jointless roof waterproofing that is deliberately free to move independently of the deck below.

PVC single-ply membrane →A plasticised PVC single-ply sheet, hot-air welded like TPO but chemically different: the plasticiser it carries is why separation from bitumen and some insulations is routine.

Reclaimed slate and tile →Slates and tiles stripped from earlier roofs and re-used, where sorting, soundness and the finite quantity actually available shape the design rather than follow from it.

Wood shingles and shakes →Small sawn or riven timber units laid in courses over spaced supports, where the split or sawn face decides how each unit sheds water and how the covering weathers.

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.

Weather barrier

Layers that shed or resist rain, wind and weather.

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.

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.

External walls · 8
Roofs · 19
External works and landscape · 1

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 roofs, walls and facades.Building envelope checklists →Preparation before envelope conversations.Durability and maintenance decisions →Preparing the upkeep side of a material decision.

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.

Building envelopeRoof Assembly Systems →Roofs answering two questions at once: where the insulation sits relative to the deck, and how the water-shedding layer achieves continuity across the whole surface.Building envelopeEnvelope Junctions, Interfaces and Terminations →The places where continuous layers stop, turn, change plane or are pierced, and several duties collide inside a very small amount of construction.

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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