Many house extensions in Berkshire fall under Permitted Development (PD) rights, meaning you don't need full planning permission. As a general guide, a single-storey rear extension up to 4m (detached) or 3m (semi/terraced) can proceed under PD. However, if you live in a conservation area, an Area of Outstanding Natural Beauty (such as parts of the North Wessex Downs), or a listed building, stricter rules apply and planning permission is almost always required. We recommend a free pre-application consultation with your local authority — and our team can handle this on your behalf.

Extension costs in Berkshire reflect the South East premium on labour and materials. A single storey extension typically runs £1,800–£2,800 per m², while a double storey extension offers better value at £1,500–£2,200 per m² because foundations and roof costs are shared across both floors. A typical 20m² kitchen extension runs £40,000–£70,000 fully fitted. For larger double storey rear extensions or side extensions the total investment varies significantly depending on specification and finish. Our home extension builders provide detailed, transparent quotes with no hidden costs before any work begins.

Build times depend on the type and size of extension. A small single storey extension up to 20m² typically takes 8–12 weeks on site. A double storey extension or two storey rear extension usually runs 16–24 weeks from groundworks to completion. Wrap-around and side extensions sit somewhere in between at 12–18 weeks. These are build times only — add 6–10 weeks for design, planning checks and structural drawings before our extension builders break ground. We provide a precise programme at the start of every project.

In most cases, no. The majority of extensions are built from the outside in, and we take great care to protect your existing home with hoarding, dust sheets, and temporary weatherproofing. The exception is typically when we break through to connect the extension to the main house — this is usually a short period of 1–3 days. We'll plan this phase to minimise disruption and always discuss it with you in advance.

• Yes — almost always. Building Regulations are separate from planning permission and ensure your extension is structurally sound, thermally efficient, and safe. They cover foundations, insulation, electrics, drainage, and fire safety. We submit all Building Regulations applications on your behalf and coordinate with the Building Control officer throughout your build.

Item descripA single storey extension adds one level to your home — typically extending the ground floor to create a larger kitchen, living space or garden room. A double storey extension adds two levels simultaneously, giving you ground floor space plus an additional bedroom or bathroom above. Double storey extensions offer significantly better value per m² because the cost of foundations and roof is shared across both floors. For homeowners in Berkshire looking to maximise space and return on investment, our home extension builders typically recommend a double storey rear extension where plot size and planning allow.tion