Ace Alfa Construction London
Loft conversion specialists London - dormer and mansard roof conversion project

Ace Alfa Construction · London

Loft conversions across London - dormer, Velux, mansard and more

Ace Alfa Construction delivers loft conversions across all London boroughs - adding an extra bedroom, bathroom, or home office without touching your garden. We manage structural design, building regulations, and full interior fit-out. Most loft conversions complete within 8-12 weeks on site.

Get a Free QuoteCall 07878 537 554

Overview

Types of loft conversion we deliver

The right loft conversion type depends on your roof structure, head height, and budget. We assess and advise at the free site visit.

  • Dormer Loft ConversionThe most popular type in London. A box-shaped structure is added to the rear roof slope, creating full head height and a proper room. Suits most terraced and semi-detached houses.
  • Velux (Rooflight) ConversionThe simplest and most affordable option. Roof windows are added to the existing slope without changing the roof shape. Requires good existing head height - minimum 2.2m to ridge.
  • Mansard ConversionReplaces one or both roof slopes with a near-vertical wall and flat roof, maximising usable floor space. Common in London terraces and requires planning permission in most cases.
  • L-Shaped DormerTwo dormer structures joined at right angles - typically across the rear and the return of an L-shaped Victorian or Edwardian house. Creates the largest possible loft space.
  • Hip-to-Gable ConversionExtends a hipped roof end to a vertical gable wall, adding floor area at the eaves. Often combined with a rear dormer. Common on semi-detached and end-of-terrace properties.

Why us

Why choose this service

  • Add a bedroom without losing garden spaceA loft conversion is one of the most efficient ways to create an extra bedroom or bathroom in a London home - no footprint change, no garden lost.
  • Increase your property value by up to 25%Loft conversions consistently rank among the highest-return home improvements in London. An extra bedroom in the loft can add significant value at resale.
  • Full structural and interior deliveryWe manage structural engineering, insulation, roofing modifications, staircases, electrics, plumbing, and finishing - all under one contract.

How we work

Our process

  1. Structural and roof assessmentWe assess your roof type, head height, and structural requirements to determine the right conversion type and confirm feasibility before any cost is committed.
  2. Building regulations and roof alterationsWe prepare and submit all building regulation drawings, manage structural steelwork or timber modifications, and handle any required party wall notices.
  3. Interior fit-out and finishingStaircase installation, insulation, boarding, electrics, plastering, and decorating are all completed by our team to deliver a fully finished, move-in-ready room.

Scope

What's included

  • Structural assessment and roof surveyWe confirm your roof type, head height, and structural feasibility before any design or cost is committed.
  • Architectural drawings and building regulationsWe prepare or commission all required drawings and submit building regulation applications on your behalf.
  • Structural steelwork or timber alterationsAny structural changes to your roof - new beams, ridge alterations, or rafter modifications - are designed by a structural engineer and carried out by our team.
  • Staircase design and installationA new staircase is designed to meet building regulation requirements for headroom and rise, and installed by our carpentry team.
  • Full interior fit-outInsulation, boarding, plastering, electrics, windows, flooring, and decoration - all completed to a fully habitable standard.
  • En-suite bathroom (where included)Where your loft conversion includes an en-suite, we manage all plumbing, tiling, sanitaryware, and electrics as part of the same contract.

Recent work

Case studies

Mansard loft conversion structure during construction in London

Central London

Loft Master Suite Build

Mansard loft conversion in Central London creating a full master suite with en-suite bathroom, integrated storage, and Juliet balcony. Project completed in 11 weeks including all building regulations.

Finished loft bedroom conversion with fitted storage in London

South London

Family Loft Bedroom Conversion

Dormer loft conversion adding a large double bedroom and shower room for a family in South London. Velux front windows, full insulation upgrade, and new staircase installed.

Answers

Frequently asked questions

Is my loft suitable for conversion?

We assess head height, structure, and layout to confirm feasibility and recommend the most practical conversion option.

Will insulation and comfort improve after conversion?

Yes. Loft conversion work includes insulation upgrades designed to improve comfort and long-term performance.

Do I need planning permission for a loft conversion in London?

Most loft conversions fall under Permitted Development and do not require planning permission, provided they meet volume limits and design conditions. Exceptions include properties in conservation areas, listed buildings, flats, and certain mansard conversions. We confirm your planning status at the site assessment stage.

How much does a loft conversion cost in London?

Costs depend on the conversion type, size, and interior specification. We provide a full written quote following your free site assessment.

How much head height do I need for a loft conversion?

You generally need a minimum of 2.2 metres from floor to ridge. We measure this at the site visit. If your current head height is lower, we may be able to raise the ridge or recommend a dormer solution to create the required space.

Explore

Related services

Loft conversions often combine with other projects.

House ExtensionsExtend below while converting above for maximum space.Bathroom RenovationAdd an en-suite to your new loft bedroom.Full RenovationCombine your loft with a whole-house refurbishment.