Loft Conversions in Wandsworth
Rear dormer, L-shaped, hip-to-gable and mansard loft conversions across Wandsworth, Southfields, Earlsfield and Wandsworth Common. Free site visit, then a fixed-price quote.
Our fixed-price quote is based on the agreed written scope. Client-requested changes and unforeseen work are priced and approved separately before proceeding.
07564 041115Why Wandsworth Homeowners Convert Their Loft
SW18 is mostly Victorian and Edwardian terraces, with Edwardian semis and some larger houses around Wandsworth Common. Most of them have roof space that can become a bedroom and bathroom, and Wandsworth Council's Housing SPD is unusually specific about which roof shapes it will accept on which kind of house.
At a free site visit we check the roof structure, head height, stair position and planning route before anything is designed, then give you an itemised fixed-price quote. Our Southfields dormer loft is nearby in SW18.
Our fixed-price quote is based on the agreed written scope. Client-requested changes and unforeseen work are priced and approved separately before proceeding.
Conversion Types
Rear Dormer
The standard loft for a mid-terrace in SW18: a box-shaped extension on the rear roof slope with a near-vertical back wall, giving full head height across most of the room for a double bedroom and often a shower room.
L-Shaped Dormer
A rear dormer on the main roof joined to a second dormer over the back addition. To limit the impact on neighbours, the Housing SPD suggests keeping the part over the back addition to less than half the back addition's length.
Mansard
The rear slope is rebuilt at a steep angle with a flat or shallow roof above. On mid-terraces where the party walls rise through the roof, Wandsworth's Housing SPD describes a full-width mansard-style rear addition as the simplest approach and favours a sloping face of about 70 degrees. It's the type most likely to need full planning permission.
Hip-to-Gable
On a semi or end-of-terrace house with a hipped roof, the hip is built up into a vertical gable, usually with a rear dormer. The SPD says not to convert a hip where it would spoil a consistent roofscape, and that hip-to-gable conversions are "generally not acceptable in conservation areas".
Velux / Rooflight
The roof stays as it is and rooflights go into the slopes. The simplest option, but it only works where there's already enough head height under the ridge.
Planning in Wandsworth
Outside conservation areas, the national Class B rules apply: up to 40 cubic metres of extra roof space on a terrace or 50 on other houses, including earlier roof extensions, nothing above the ridge and no dormers on a front slope facing the road. Wandsworth has 46 conservation areas, and in all of them a dormer needs a householder application. Eight also have Article 4 Directions that bring smaller changes, such as windows and roof coverings, under control.
Why Bluebird Spaces
Loft conversion prices in Wandsworth
We publish one typical band, for the rear dormer with an en-suite that most terraces get. Other loft types are priced at the site visit, because roof structure, stair position and planning route vary so much.
| Type | Typical build price (ex VAT) | Notes |
|---|---|---|
| Rear dormer with en-suite | £80,000–£90,000 | Our typical loft conversion. |
| L-shaped dormer | Priced at site visit | Main roof dormer joined to a dormer over the back addition. |
| Hip-to-gable (usually with a rear dormer) | Priced at site visit | For semi-detached and end-of-terrace houses with a hipped roof. |
| Mansard | Priced at site visit | Rebuilds the rear slope; the type most likely to need planning. |
| Rooflight (Velux-style) | Priced at site visit | Only works where there is already enough head height. |
Typical project build prices, excluding VAT and professional fees (design, structural engineer, Building Control, party wall and planning fees). Prices are the same across every borough we cover; access and logistics (parking, skips, scaffold, restricted access) can affect the final price. Your fixed quote follows a site visit.
Our fixed-price quote is based on the agreed written scope. Client-requested changes and unforeseen work are priced and approved separately before proceeding.
Wandsworth's Article 4 areas and what they mean for a loft
Wandsworth's Article 4 page lists eight conservation areas with Article 4 Directions: Dover House Estate, Heaver Estate, Latchmere Estate, Putney Lower Common, Roehampton Village, Shaftesbury Park Estate, Totterdown Fields Estate and Wandsworth Common. The council's own words are that a direction "does not prevent the development to which it applies, but instead requires that planning permission is first obtained".
A conservation area alone already rules out a permitted development dormer, so a loft in any of the 46 conservation areas goes through a householder application (£548 from April 2026). Magdalen Park is not an Article 4 area: Wandsworth says the 2023 direction was not confirmed and was removed, though normal conservation-area controls still apply. Our Wandsworth Article 4 guide explains how to check your address in five minutes.
Hip-to-gable and corner houses in Wandsworth
The Housing SPD treats corner and end-of-terrace houses differently from mid-terraces. It says a rear mansard-style addition should be avoided on these houses, because the change to the gable would be visible from the street, and recommends a well-proportioned rear dormer set below the ridge and in from the edge instead. On corners, a hip-to-gable (if acceptable) shouldn't be combined with a rear mansard.
So on an Edwardian semi in SW18 the usual answer is a hip-to-gable plus rear dormer outside conservation areas, checked against the 50 cubic metre allowance, and a carefully sized rear dormer inside them.
Lawful Development Certificates in Wandsworth
If your loft is permitted development, a Lawful Development Certificate (£274 from April 2026) is the proof a buyer's solicitor will ask for. In our London Planning Datahub pull of 2 October 2026, Wandsworth refused 39 of the 256 proposed-use certificates it decided in the year, about 15%, and 13 of 118 loft-related ones (11%). A refusal usually means a redesign and another wait of up to eight weeks, so the volume calculation needs to come from a measured survey. Our loft LDC guide explains the rules that trip applications up.
Our Wandsworth loft work
Our Southfields dormer loft conversion took 14 weeks from start to finish and included structural steelwork, dormer construction, upgraded insulation, rooflights and complete internal finishes. For a loft combined with other work, our Wimbledon whole-house renovation added a loft with a shower room alongside a rear extension.
Our Work Near Wandsworth
Projects we have built in and around Wandsworth. Each one links to the full write-up with photos.
Southfields, Wandsworth, SW18
Southfields Dormer Loft Conversion
14 weeks from start to finish on site
- Full loft conversion
- Dormer construction
- Structural steelwork
Wimbledon, South West London, SW19
Wimbledon Whole-House Renovation, Loft Conversion & Rear Extension
- Complete strip-out and whole-house renovation
- Loft conversion with shower room
- Rear kitchen and dining extension
Richmond, South West London, TW9
Richmond Loft Conversion with En Suite
500 sq ft additional space
- Loft conversion
- New bedroom suite
- Ensuite bathroom
“We chose Ben/Tom/Milen and team over recommended builders from friends after meeting them in person. They were knowledgeable and explained each part the process/works in terms that I could understand and clearly explained any terminology. This helped build trust at the outset and their pricing…”
How a loft conversion with us runs
Step 1
Free site visit
We visit, measure up and assess the existing structure, access and any party wall implications, then explain the practical next steps. No obligation.
Step 2
Fixed-price quote
An itemised quote for the build, excluding VAT and professional fees (design, structural engineer, Building Control, party wall and planning fees), which are quoted separately.
Step 3
Approvals
Working with your architect, the drawings are developed and submitted for planning if required, and party wall notices are served to neighbours if needed. We plan the start date around them.
Step 4
Build
The programme is set out before work starts. If you change the scope, we price the change and agree it with you first.
Step 5
Handover
Final inspection, a snagging walk-through with you, and keys handed over.
Federation of Master Builders members
Bluebird Spaces is a member of the Federation of Master Builders.
View our FMB profileTalk to us about your Wandsworth project
Call us, or send the enquiry form and we'll arrange a free site visit.
Common Questions
Wandsworth coverage and nearby work
We cover Wandsworth Town, Southfields, Earlsfield, Wandsworth Common and the surrounding SW18 streets. Our Southfields dormer loft conversion, Earlsfield side-return extension, Wandsworth rear kitchen extension and Wandsworth new build are all in the borough.
Ready to talk about your project?
Free site visit, then a fixed-price quote. No deposit upfront.