Permitted Development Extensions in Denham

We provide clear, professional guidance on permitted development extensions in Denham and surrounding areas. Whether you’re planning a rear, side, or two-storey extension, understanding local planning constraints and national permitted development limits is essential before work begins.

Common Permitted Development Issues in Denham

• Incorrect measurement from original dwelling
• Outbuilding positioned forward of principal elevation
• Extension within a conservation area in Denham
• Side extension exceeds half the width of the original house
• Extension covering more than 50% of garden area
• Rear extension exceeds permitted projection limits Denham

Property Types We Advise On in Denham

• New build developments
• Victorian properties
• Bungalows
• Terraced houses
• Properties with outbuildings

Frequently Asked Questions

How is the original house defined for measurement purposes?

The “original house” refers to the property as it stood on 1 July 1948 or when it was first built, not including later extensions.

Can I convert my loft and add a dormer?

Dormer loft conversions are often permitted development within volume limits.

What is the maximum rear projection allowed?

Detached houses may extend up to four metres under standard rules, or eight metres with prior approval. Smaller limits apply to other house types.

Do I need structural calculations?

Yes, building regulations often require structural calculations for beams, foundations, and load-bearing elements.

How long does a Lawful Development Certificate take?

Most councils determine applications within eight weeks, though timescales may vary.

Can I extend above a single-storey extension?

Possibly, but this often requires planning permission and must comply with height and design considerations.

If you're planning an extension in Denham and want to confirm whether it qualifies under permitted development rules, request a free assessment today and get clarity before you build.