Roofing options for home extensions
The roof does far more than keep the rain out. It shapes how your extension looks, how much light it lets in and what it costs. Here are the main options to consider.
Choosing a roof shape
Before you settle on a style, weigh up three things: your budget, whether you want a contemporary or traditional look, and whether you might want to use the roof space in future, a shallow pitch can rule out a later conversion. The main shapes are:
- Monopitch: a single sloping plane, great for maximising height and light on one side.
- Duopitch: two slopes meeting at a ridge, with gable ends.
- Hip: slopes on all sides, meeting neatly at the corners.
- Lean-to: a simple single slope against the house, ideal for rear extensions and roof lights.
- Flat or parapet: a low-profile modern look that can be hidden behind a parapet on period homes.
Flat or pitched?
Flat roofs have become much more popular as modern EPDM and single-ply membranes have largely eliminated the leaks associated with older felt roofs. They are economical, keep the roofline low and suit contemporary designs and roof lanterns. Pitched roofs allow vaulted ceilings, shed water quickly and tend to sit more comfortably on traditional houses.
Your roof, planning and building regulations
A pitched roof that rises above the existing ridge, or that changes the look of the house significantly, may need planning permission: while roof lights, re-covering and some dormers can often be done under permitted development. Either way, the roof must meet the Building Regulations for structure, insulation and weather-tightness.
Roof tiles and coverings
- Slate: elegant and long-lasting; natural slate costs more than man-made.
- Clay: attractive and eco-friendly with a long life, though more brittle and pricier.
- Concrete: a durable, cost-effective all-rounder that can mimic slate or clay.
- Interlocking: quick to lay and economical, the most common UK choice.
- Large-format: fast to install and lighter, keeping labour and support costs down.
The right covering depends on the pitch, the look you want, the weight the structure can carry and your budget. Our structural engineers and designers will help you choose.
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