Home → Cost guides → Loft conversion cost
Loft conversion cost: what it really costs in 2026
Velux, dormer and hip-to-gable — what each costs and what actually happens.
£26,000 – £78,000
A rooflight (Velux) conversion starts around £26,000. A dormer with bedroom and en-suite typically lands between £48,000 and £78,000 depending on size and spec.
Price by spec
| Option | What it means | Typical price |
|---|---|---|
| Velux / rooflight | Good existing head height, simplest build | £26,000 – £42,000 |
| Hip-to-gable | Semis and end-terraces needing width | £45,000 – £63,000 |
| Dormer | Adding head height and floor space | £48,000 – £78,000 |
What actually happens
- Survey and structural design — head height and floor strength checked
- Scaffolding up; roof opened or dormer framed
- New floor structure and steel beams installed
- Roof windows or dormer built and made watertight
- Insulation, first-fix electrics and plumbing
- Staircase fitted and walls plastered
- Second fix, doors, decoration and snagging
Popular choices
Dormer with Juliet balconyBuilt-in eaves storageEn-suite shower roomVelux with blackout blinds
Regulations to know
- Building regulations always apply — structure, fire escape and insulation are inspected
- Most lofts fall under permitted development, but front-facing dormers and conservation areas need planning permission
- Terraced or semi-detached? The Party Wall Act usually applies — notify neighbours early
Tips from the trade
- Check head height first: you need roughly 2.2m at the ridge before it's worth pricing
- An en-suite adds several thousand but adds the most value per pound spent
Plan this project properly
Get a region-adjusted estimate, track budget against real quotes, and find local tradespeople -- free to browse on Qome.
Start planning on QomePrices on this page are approximate, region-adjusted guide figures built from cross-checked UK cost data. They exist to inform you, not to bind anyone. Actual prices are whatever you and your tradesperson agree, and a difference between a Qome guide figure and a real quote is not a fault in either.