Service · London
Loft Conversions in London
Turn unused roof space into a master suite, home office or family room. We design and build dormer, mansard, hip-to-gable and L-shape loft conversions across London — from structural opening to finished ensuite.

Why Prime Build
What you get when you
work with us.
The same in-house team, the same five-stage process, the same 10-year guarantee — across every service we offer.
- Dormer, mansard, hip-to-gable & L-shape loft conversions
- Structural calculations, steel beams and full building-control coordination handled in-house
- Bespoke ensuite design (see our Richmond loft conversion case study)
- Average completion: 10–14 weeks from start to handover
- Adds an average 20–22% to UK home values
Our process
A five-stage process built to remove surprises.
01
Survey
Roof survey to confirm head-height, structural feasibility and conversion type.
02
Design
Loft layout, dormer/mansard design, ensuite planning and natural-light strategy.
03
Permits
Building control, party-wall agreements and planning (where needed) handled by us.
04
Build
Scaffold, structural openings, steels, joists, insulation, plasterboard, finishes — typically 10–14 weeks.
05
Handover
Sign-off, warranty and full snagging walk-through.
Recent loft conversions
Selected projects.

Extension · Richmond, TW10
Richmond Loft Conversion — Ensuite Bathroom

Extension · Richmond, TW10
Richmond Loft Ensuite — Walk-In Shower

Extension · Richmond, TW10
Richmond Loft Ensuite — Industrial Vanity

Extension · Richmond, TW10
Richmond Loft Conversion — Master Bedroom

Extension · Richmond, TW10
Richmond Loft Conversion — Bedroom

Extension · Richmond, TW10
Richmond Loft Family Bathroom
Frequently asked questions
Answers about loft conversions.
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