British roofs come in a small number of shapes and a larger number of coverings, and the pair together decides almost everything about what a roof costs to own. This page separates the two questions, because owners often ask about a material when the thing constraining them is the shape, and about a shape when the thing constraining them is the pitch.
The shapes you will meet
Gable roofs, with two slopes and a wall at each end, are the default on terraces and semis. Hipped roofs slope on all four sides and are common on interwar and postwar detached housing. Mono pitch or lean-to roofs cover extensions and outbuildings. Flat roofs, which are never truly flat, cover garages, dormers and modern extensions. Mansards and gambrels appear where a floor was wanted inside the roof. Each shape sets how much detail the roofer has to form, and detail is what a roof is priced on.
The coverings, and what each is good at
Natural slate is the longest lived and the most expensive, and on an old roof it is often the fixings rather than the slates that have failed. Clay plain tiles suit steep pitches and small units of detail. Concrete interlocking tiles are the cheap and quick default on postwar housing and are heavy. Metal, whether standing seam or profiled sheet, covers low pitches that a tile cannot. Reinforced bitumen, fibreglass and rubber membranes cover the flat roofs. Thatch and stone slate are regional and specialised.
How long each tends to last
Service life on a roof is set by the weakest part rather than the headline material, which is why a slate roof can need stripping at eighty years while the slates themselves are fine: the nails have corroded. Concrete tiles outlast the felt underlay beneath them, so a re-roof is often driven by a perished underlay rather than a broken tile. Flat roof membranes are outlived by their decks when the deck is dry and killed by them when it is not. On any roof, the flashings and the leadwork are the first thing to fail and the cheapest thing to renew.
Questions people ask about types of roofs
What is the best roofing material in the UK?
There is no single answer, because the pitch, the exposure, the structure's load capacity and any conservation constraint each rule out options before preference gets a say. The useful question is which coverings your pitch and your structure allow, and then which of those you want.
Can I change my roof covering to a different material?
Sometimes. Weight is the first constraint, because a structure designed for slate may not take concrete tiles, and pitch is the second. In a conservation area or on a listed building the appearance is also controlled.
Which roof type is cheapest to build?
A simple gable roof covered in concrete interlocking tiles, because it has the fewest lines of detail and the cheapest large-format covering. Cheapest to build and cheapest to own are not always the same roof.