The roof will play an important role in defining the appearance of your home and, of course, needs to be an effective shield against the elements.
The type of covering you choose will be part of the overall design strategy, but may also need to reflect the environment around you. For example, your local authority could ask you to match the slate of neighbouring properties or stipulate a green roof so your house blends into an open rural landscape.
The roof pitch and profile also needs to come into play. “The golden rule in roof design is not to force a material to do something it can’t technically do,” says Steven Harris from CRSH Architects. “For instance, slate can’t be laid at a low pitch.”
Metal roofing is popular for its durability, lifespan and weathering. It is also relatively lightweight and has the flexibility to work with most roof shapes in a way that would be impossible with traditional tiles – metal can be installed onto a roof pitch as low as 3°, for example.
This material requires fewer joints than tiles, is quick to install and low maintenance. It’s also easier to conceal details, such as gutters and pipes, to enhance the profile of the roof shape. However, be aware that metal can promote a flat aesthetic compared to the texture of traditional coverings.
Zinc (around £140 per m2) is available in various colours and popular in contemporary designs. Solar panels clip easily onto the seams and the sheets can be used to clad the walls and roof for a streamlined appearance. Corrugated aluminium is priced at roughly £30 per m2, plus £5 per m2 for fixings – while standing seam versions will cost around £80 per m2.
“The bare metal has a space age quality about it that gives a strong contemporary aesthetic,” adds Alan Dickson from Rural Design Architects.
Camillin Denny Design are cladding the walls and roof of a new property in Cornwall in double standing seam copper (from £160 per m2). “The first question everyone asks about copper is when it will turn green,” says Mark Camillin from the company. “It could take anything from 40-60 years depending on the exposure, but the roof still looks fantastic in its raw, shiny state.”
Steel roofs in houses tend to be standing seam systems that are mechanically secured, like the click fix system Colorcoat Urban from Tata Steel (priced at around £60-100 per m2 supply and installed, depending on the project).
Colorcoat Urban is suitable for both roofs and walls; it curves naturally to a 6m radius and can be pre-rounded to 2.5m making it suitable for all kinds of roof shapes. It comes in a range of colours and coordinating roof accessories and solar panels can be attached, too.
Contemporary roof profiles
An ultra-modern roof shape will add to the 21st-century aesthetic of your home. Here are some of the most popular options:
The monopitch roof on this house by CRSH Architects in Monmouthshire is clad in dark grey corrugated concrete sheeting. The roof shape is designed to follow the angle of the Skirrid mountain range behind the dwelling, while also maximising the roof area for photovoltaics and solar thermal panel application.
The use of glass by glazing supplier Tombe in the double-pitched roof of this steel-framed extension shows traditional architecture and contemporary materials can sit beautifully alongside each other
Giles Pike Architects has installed a flat roof on this London extension. It’s an integral part of the modernist design, enhanced by frameless glazing to draw in natural light.
A big plus of single-ply PVC roofing membranes is they’re easy to install. The materials are hot welded onto a flat roof deck to create one solid waterproof covering. The membrane is flexible, resistant to UV radiation and options such as Sarnafil’s single ply product (which costs around £80-£120 per m2) can last in excess of 40 years.
It’s also possible to create the appearance of a sharp, modern roof with pre-formed PVC coated steel edges, to which the membrane is welded. Single-ply coverings can also mimic the look of zinc, steel or copper roofs by using standing seams.
Installing a waterproof wall membrane and single-ply means that you can envelope the walls and roof of a house in a single material. The decorative cladding then acts as the rainscreen. “The effect looks very sharp; as though you’ve hewn the house out of a block of wood,” says Mark Camillin.
“My only reservation is the zone between the cladding and membrane filling up with leaves or nesting birds.” If you do decide to go down this route, be aware of the extra costs involved to fit the roof and the rainscreen finish.
These coverings are great for blending a house into the landscape or to soften the appearance in an urban setting. They’re normally built on top of a single-ply surface and the waterproofing needs careful attention.
Be aware that a green roof is heavy, so you’ll need stronger structural roof members than usual to cope with the extra load. “There is enormous interest in creating green roofs,” says Tom Pike from Giles Pike Architects. “They are great for wildlife and can look impressive, but you need the right planting regime and time to maintain them.”
The beauty of clay tiles lies in their array of shades, textures and profiles, which complement brick and render. Slate has a crisp finish in tones of grey, black, green and blue that works well with zinc. Slate and clay are both natural, fire-resistant materials and long-lasting, although sometimes tiles can crack or break.
Neither material is suitable for low roof pitches and they are heavier than metal and concrete, so the roof structure will need to be sized accordingly. Concrete tiles could be considered as a cheaper alternative, but the material doesn’t weather as well.
The strong colour of Dreadnought’s Staffordshire Blue (pictured above) cost from £29.38 per m2. These smooth-faced units are a good example of a traditional clay tile being used to create a contemporary aesthetic. The tight dimensional tolerances accommodate curves, and in this Cotswolds house below, are curved around a barn-style roof that hangs around the structure.