Ambleside Avenue, Streatham SW16
L-shaped dormer adding a master bedroom and en-suite to a large Victorian terrace near Tooting Bec Common.
- L-Shaped Dormer
- 11 weeks
- £68k
- Lambeth Council
- Delivered by us
Loft Conversions in Streatham SW16
The London Loft Conversion Company designs and builds loft conversions across Streatham and the surrounding SW16 and SW2 postcodes, around 30 minutes from our Fulham base. One in-house team for feasibility, design, planning, structural engineering and the build itself. One fixed price, VAT included, written contract.
- Typical project
- £52k–£65k, 8–12 weeks
- Area
- Streatham SW16 (SW2)
- Local council
- Lambeth
- Best for
- Victorian and Edwardian terraces and semis
Why Streatham lofts give you more space for your money
Streatham has some of the best-value period housing in south London: street after street of large Victorian and Edwardian terraces and semis, most built between the 1880s and the 1910s as the railway pushed the suburb outwards. The houses are noticeably bigger than much of the stock closer to town, with wide roof spans and generous loft volumes that convert brilliantly. L-shaped dormers over the rear outrigger and straight rear dormers both deliver full-height rooms with space to spare.
Planning sits with Lambeth Council across Streatham, Streatham Hill and Streatham Common, which keeps things simpler than areas split between boroughs. A full application typically takes 8 to 10 weeks; Lawful Development Certificates are usually decided in around 6. The Telford Park and Streatham Lodge conservation areas restrict some roof alterations, so on those streets a mansard or a low-impact Velux conversion is often the smarter route.
We're around 30 minutes by road from our Fulham base, straight through Wandsworth and Balham, so survey visits in Streatham are easy to arrange, usually within the same week. And because Streatham lofts are bigger than most, the cost per square metre of finished space here is among the best of any area we build in.
Recent loft conversions in Streatham
A selection of dormer, L-shaped, mansard and Velux projects we've delivered across SW16 and Streatham Hill, labelled clearly so you can see whether the build was through The London Loft Conversion Company or our parent company, Pillarstone Operations Group.
Telford Avenue, Streatham Hill SW2
Rear mansard creating a full new storey on a late-Victorian house within the Telford Park conservation area.
- Mansard
- 14 weeks
- £84k
- Lambeth Council
- Delivered by us
Sunnyhill Road, Streatham SW16
Rear dormer with double bedroom and walk-in shower on an Edwardian terrace just off Streatham High Road.
- Dormer
- 9 weeks
- £56k
- Lambeth Council
- Delivered by us
Pendennis Road, Streatham SW16
Rear dormer creating two bedrooms with a reconfigured landing on a Victorian mid-terrace near Streatham station.
- Dormer
- 10 weeks
- £61k
- Lambeth Council
- Group-delivered
Mount Ephraim Road, Streatham SW16
Velux conversion turning a deep, high-ridge loft into a guest bedroom and study without altering the roofline.
- Velux
- 7 weeks
- £42k
- Lambeth Council
- Group-delivered
Gleneagle Road, Streatham SW16
L-shaped rear dormer with a bathroom and built-in storage over the outrigger of an Edwardian terrace.
- L-Shaped Dormer
- 12 weeks
- £72k
- Lambeth Council
- Group-delivered
Our projects in and around Streatham
Which loft conversion suits a Streatham home?
Streatham's period stock splits into terraces with rear outriggers, wider semis and a handful of conservation-area streets. Here's what usually works on each.
Rear DormerWhy it suits Streatham
The most cost-effective option for Streatham's Victorian and Edwardian terraces, and the reason SW16 is such good value: the roofs are big, so a straightforward rear dormer often yields a master bedroom and en-suite with headroom to spare. Usually permitted development.
£52,000 – £65,000
Read more about rear dormersL-Shaped DormerWhy it suits Streatham
Most Streatham terraces have a rear back addition ("outrigger"), which is exactly where an L-shaped dormer sits. Adds two rooms, usually a master bedroom and a generous bathroom, within permitted development on the vast majority of houses outside the conservation areas.
£62,000 – £76,000
Read more about l-shaped dormersMansardWhy it suits Streatham
Where the Telford Park or Streatham Lodge conservation areas restrict rear dormers, a mansard rebuilds the rear roof at a steep angle and creates a full new storey with vertical walls inside. The highest-spec option for the large late-Victorian houses around Streatham Hill.
£70,000 – £92,000
Read more about mansardsPlanning permission in Streatham: what you actually need to know
When you'll usually need planning permission in Streatham
- Mansards, in almost every case
- Front-facing dormers, almost always
- Any conversion of a flat or maisonette
- Properties within the Telford Park or Streatham Lodge conservation areas
- Listed buildings (rare in SW16 but worth checking)
- Properties where previous extensions have used up the permitted development "allowance"
- Anything that significantly alters the ridge line or chimney stacks
Conservation areas affecting Streatham
- Telford Park Conservation Area — The grid of streets around Telford Avenue on the Streatham Hill side, with large late-Victorian houses. Roof alterations visible from the street can be restricted; rear mansards and carefully detailed dormers are usually the route.
- Streatham Lodge Conservation Area — Covers streets at the southern end of Streatham towards the Common. Dormer design and materials come under closer scrutiny; we prepare the heritage statement as part of the fixed quote.
Local councils
Lambeth Council
Covers Streatham, Streatham Hill and Streatham Common
Planning portal: lambeth.gov.uk/planning
Typical planning timeline
- Full application (Lambeth Council)
- 8–10 weeks
- Lawful Development Certificates
- ~6 weeks
We handle every part of this, from Lawful Development Certificates and full planning applications to Design and Access Statements, conservation-area heritage statements, council liaison and responding to planning officer queries, as part of your fixed quote. You don't deal with the council, we do.
What does a loft conversion in Streatham cost?
Streatham is the best value of the south London areas we publish pricing for. The houses are larger, the roofs are more generous and access is usually straightforward, so you get more finished space per pound than in Clapham or Balham. The ranges below are 2026 figures for Victorian and Edwardian houses in SW16 and SW2. Final quotes are confirmed in writing after a free home survey.
| Type | Typical range | Build time | Planning |
|---|---|---|---|
| Velux | £38,000 – £46,000 | 6–8 weeks | Usually permitted development |
| Dormer | £52,000 – £65,000 | 8–10 weeks | Usually permitted development |
| L-Shaped Dormer | £62,000 – £76,000 | 10–12 weeks | Often permitted development |
| Hip-to-Gable | Quoted at survey | 10–12 weeks | Usually permitted development |
| Mansard | £70,000 – £92,000 | 12–16 weeks | Planning permission required |
VAT included. Final price varies with structural complexity, spec and finish. Your proposal is itemised line by line before any commitment.
Book a free survey for your Streatham quoteWhat our Streatham clients say
We were nervous about committing to such a big project, but the team made it the smoothest experience. They stayed on budget, finished a week early and even sorted the snags before we'd noticed them. Our bedroom is the best room in the house now.
Sarah & Tom
L-shaped dormer · Clapham
From the first survey to handover, everything happened when they said it would. The fixed price genuinely was fixed, and the weekly photo updates meant we always knew exactly where the build was. The dormer has completely changed how we use the house.
James R.
Rear dormer · Wandsworth
Our loft was a dumping ground for ten years and now it's the nicest room we own. The crew were tidy, polite and honest about what was possible, and the finish is better than we dared hope for.
Rebecca H.
Mansard · Fulham
Loft conversion questions from Streatham homeowners
How much does a loft conversion in Streatham cost?
Loft conversions in Streatham typically cost £52,000 to £92,000 depending on the type and the property. A rear dormer on a Victorian or Edwardian terrace usually falls between £52,000 and £65,000. L-shaped dormers, common on terraces with a rear outrigger, run £62,000 to £76,000. Mansards, sometimes required in the Telford Park and Streatham Lodge conservation areas, are £70,000 to £92,000, and a Velux conversion starts at around £38,000. That makes Streatham the best value of the south London areas we publish pricing for. Every figure is VAT included and confirmed in writing after a free home survey.
Do I need planning permission for a loft conversion in Streatham?
Often not. Rear dormers and L-shaped dormers on Streatham houses usually fall under permitted development, needing only a Lawful Development Certificate. You will need planning permission for a mansard, for any conversion of a flat or maisonette, and for most roof alterations within the Telford Park and Streatham Lodge conservation areas. We assess your street's exact position at the free survey and handle whichever route applies.
How long does Lambeth Council take to approve a loft conversion in Streatham?
A full planning application typically takes 8 to 10 weeks with Lambeth. A Lawful Development Certificate, which is all most Streatham dormer conversions need, is usually decided in around 6 weeks. We prepare and submit everything, deal with any planning officer queries, and build the approval time into your project programme.
Why are loft conversions cheaper in Streatham than in Clapham or Balham?
Mostly the housing stock. Streatham's Victorian and Edwardian houses are larger than much of the equivalent stock nearer town, with bigger, more accessible roofs and more straightforward structural work, so you get more finished space for less. The team, the spec and the fixed-price contract are exactly the same as every other area we build in; the price per square metre is simply better.
What's the most common loft conversion type in Streatham?
The L-shaped dormer, because most of Streatham's terraces have a rear outrigger for it to build over. Straight rear dormers are close behind, and on the wider semis around Streatham Common a hip-to-gable conversion, often combined with a rear dormer, unlocks the most space. Some of the deepest SW16 lofts have enough headroom for a Velux-only conversion.
Is my Streatham house definitely under Lambeth Council?
Almost certainly, yes. Lambeth covers Streatham, Streatham Hill and Streatham Common. A few streets at the edges of SW16 fall under neighbouring boroughs, such as the Furzedown side towards Tooting and the southern end towards Norbury. We confirm exactly which council your house falls under at the free survey and submit to the right one. The process and your fixed price are the same either way.
We also work in nearby areas
Don't see Streatham as your nearest postcode? We work across London. Most of our work comes from referrals between neighbouring streets.
- Loft Conversions in Balham
- Loft Conversions in Tooting
- Loft Conversions in Clapham
- Loft Conversions in Wimbledon
- Loft Conversions in Wandsworth
- Loft Conversions in Battersea
Looking for a specific postcode? See all the South London areas we cover or West London areas.
Ready to start your Streatham loft conversion?
Tell us your postcode and a bit about your house. Daniel will arrange a free home survey, usually within 5 working days in SW16, and you'll have a fully itemised fixed-price proposal within 7 days of the visit. No pressure, no obligation, no hard sell.
- Free home survey, usually within 5 working days in Streatham
- Itemised fixed-price proposal within 7 days of the survey
- 15% deposit only after you sign · 5% retention held until snagging is signed off
- VAT included in every figure
Prefer to talk? Call Daniel on 07414 648 263.