In detail
What matters when specifying tiled roofing
The best-looking option is not automatically the right technical choice. Roof pitch, exposure, structural capacity and the way the building is used all influence the specification. Understanding these details makes it easier to compare proposals on substance rather than appearance alone.
Clay, concrete, plain and interlocking tiles
Clay and concrete tiles are available in different shapes, colours and surface finishes. Clay can provide characteristic variation, while concrete offers a broad range of profiles and finishes. Neither material should be treated as universally right for every roof. Product dimensions, permitted pitch, weight and fitting requirements need checking against the building and the intended appearance.
Plain tiles generally use a double-lap arrangement, while interlocking tiles use shaped connections and their own overlap requirements. These systems differ in setting out, tile numbers and detailing. A low-pitch interlocking product is not interchangeable with a traditional plain tile simply because both are described as roof tiles. Select the exact product first, then coordinate battens, fixings, eaves and compatible fittings around it.
Underlay, battens and ventilation work together
Slates and tiles shed most rainfall, while the underlay provides a secondary line of protection beneath them. Underlay laps, support and drainage at the eaves must suit the roof design. Battens provide the fixing positions for the covering, so their grade, spacing and support matter. A covering installed over unsuitable battens or poorly arranged underlay can conceal problems rather than solve them.
A breathable membrane does not automatically remove the need for ventilation. The arrangement depends on the roof construction, insulation position, membrane specification and moisture conditions inside the building. Cold roof spaces and insulated roof slopes need different consideration. Blocking the eaves with insulation, or adding ridge ventilation without a suitable overall strategy, can leave moisture trapped where it causes condensation and timber deterioration.
Fixing patterns, dry ridges and roof edges
A fixing specification considers the chosen tile, wind exposure and the roof’s geometry. Nails, clips or other specified fixings help resist uplift, with particular attention often needed at edges and other exposed locations. Correct batten gauge maintains the required headlap. Stretching the gauge to avoid an awkward final course can compromise the covering, so careful setting out is important before laying progresses.
Dry ridge and dry verge systems can provide mechanically secured details without relying on mortar alone, but they still need to suit the tile and installation conditions. A ventilated dry ridge must form part of a coherent ventilation design. Mortar-bedded details also need appropriate mechanical fixing where required. The right choice is the complete compatible detail, not a blanket assumption that one edge treatment suits every tiled roof.
Junctions, rainwater and approvals
Water concentrates at valleys and changes direction around chimneys, rooflights and adjoining walls. These locations need compatible flashings, adequate overlaps and unobstructed drainage. Lead flashing must accommodate movement and be detailed for its location; simply adding sealant over a failed junction is not equivalent to rebuilding it correctly. Eaves details must direct water into the gutter rather than behind the fascia or onto vulnerable timber.
Building Regulations approval is normally required for substantial re-roofing, and thermal upgrades may need consideration where applicable. Planning permission is a separate question: listed buildings, conservation areas and some alterations can have additional restrictions. Establish the relevant route before work starts. Structural changes or a materially different covering load may also require professional assessment rather than an assumption that the existing roof can accommodate them.
Occupied homes and commercial premises
On an occupied home, roof work needs to account for people moving through entrances, items stored in the loft and rooms directly beneath the work. Dust and disturbance cannot always be eliminated, but discussing likely effects helps you prepare. Extensions, porches and adjoining roofs also need attention because the main roof must connect to them without creating awkward drainage or maintenance problems.
Commercial premises may have different access constraints, shared boundaries or activities that cannot simply stop during roofing work. The appropriate sequence depends on the building, not just the covering selected. Explain opening hours, sensitive internal areas and any restrictions on scaffolding or deliveries before the scope is agreed. A realistic plan should also account for weather interruptions rather than treating the proposed programme as an unconditional completion guarantee.

