Plan Then Build

Dormer loft conversion cost in East of England

East of England build costs run at 108% of the UK national average, across councils including Cambridge, Norwich, Ipswich. A 20m² example at mid-range spec: £80,307–£108,650. Adjust the size and spec below for your project.

Permitted Development & Cost Checker

England only. Takes about a minute.

Dormer loft conversion cost by size and spec in East of England

SizeBasicMid-rangePremium
15£41,826–£56,589£60,230–£81,488£86,255–£116,698
20£55,769–£75,452£80,307–£108,650£115,007–£155,598
30£83,653–£113,177£120,460–£162,975£172,511–£233,397

Does a dormer loft conversion need planning permission?

Council planning fees in East of England

Each council sets its own fees and decision times. See your council’s page for the exact figures.

Dormer loft conversion cost in other regions

Cost bands refreshed quarterly from published 2026 UK cost guides.