A Velux loft conversion turns your existing loft into a bright, finished room without changing the shape of your roof.
Rooflight windows are set into the slopes, the structure stays exactly as it is, and the work is done in 6–8 weeks with less disruption than any other conversion type. It's also the most affordable route into the loft, and it almost never needs planning permission.
We design and build Velux conversions across London with everything handled in-house, from feasibility through to final snagging.
01
A Velux loft conversion works entirely within your existing roof envelope. Velux or similar rooflight windows are set into the slopes, the floor is strengthened and insulated, and a proper staircase goes in, all without any structural extension to the roof.
02
Around 6–8 weeks on site, with the full process taking roughly 12–16 weeks from your first call to handover. No other conversion type gets you a finished room faster.
03
Almost always permitted development on houses, because nothing extends beyond the existing roof (Lawful Development Certificate and Building Control sign-off still required). Even conservation areas that refuse dormers will usually accept rooflights.
04
A site manager you know by name. Weekly photo updates by WhatsApp. The same trade teams we've worked with for over seven years. No rotating subcontractors, no agency labour walking in and out.
Each project is labelled with the time on site, the final price and the council that covered it.
Two-slope Velux conversion creating a bright home office on an Edwardian terrace.
Four-rooflight guest bedroom in a conservation area where dormers were off the table.
Velux conversion with a double bedroom and compact shower room on a Victorian terrace.
Three-rooflight study and reading room on a tall-roofed Victorian terrace.
Rooflight conversion adding a guest bedroom in the West Greenwich conservation area.
High-ridge Velux conversion creating an artist studio under the original slopes.
Not sure which side you fall on? Daniel will tell you straight at the free survey. book one here →
| Type | Build time | Floor area added | Planning | Best for |
|---|---|---|---|---|
| Velux | 6–8 weeks | Smallest | Usually permitted development | Homes with enough existing headroom and a leaner budget |
| Dormer | 8–10 weeks | Large | Usually permitted development | Victorian and Edwardian terraces, 1930s semis |
| L-Shaped Dormer | 10–12 weeks | Largest (two rooms) | Often permitted development | Victorian terraces with a rear back addition |
| Hip-to-Gable | 10–12 weeks | Large | Usually permitted development | Semi-detached and end-of-terrace with hipped roofs |
| Mansard | 12–16 weeks | Largest single room | Planning permission required | Conservation areas, period properties needing maximum space |
From your first call through to the day you move back in: a clear, predictable timeline that protects your home and your schedule.
Step 01
Daniel measures your ridge height and usable headroom, checks the rafters and services, and tells you on the visit whether a Velux conversion will work.
Step 02
Design drawings, the rooflight layout and a fully itemised fixed-price proposal, with every cost on its own line. A 15% deposit secures your build slot.
Step 03
A Lawful Development Certificate puts permitted development in writing, with floor calculations and Building Control lodged alongside. Party wall notices only where the new floor bears on a shared wall.
Step 04
Your roof never comes off: each rooflight is cut, fitted and weathered the same day. Floor, insulation, services and finishes complete in 6–8 weeks. Weekly photo updates by WhatsApp.
Step 05
Final walk-around, completion certificate and written guarantees. 5% stays in retention until you've signed off the snagging.
A Velux loft conversion in London typically costs £38,000 to £48,000, VAT included. The lower end gets you a study or guest room with carpet and standard finishes.
The mid-range adds more floor area, extra rooflights and engineered wood floors. The upper end gets you a double bedroom with a compact shower room, premium finishes and fitted eaves storage.
Every figure is itemised line by line before you sign, with no provisional sums.
Rarely. Because the conversion happens entirely within your existing roof and the rooflights sit almost flush with the slope, it falls under permitted development on nearly every house, including many conservation areas where a dormer would be refused.
We still apply for a Lawful Development Certificate so you have the position in writing, and Building Control sign-off is always required.
Flats and maisonettes do need planning permission, but rooflight schemes are usually the easiest of all to get approved.
Around 6 to 8 weeks on site, the shortest build of any conversion type. The roof never comes off, so there is no weatherproofing stage and no external structure to build.
The strengthened floor goes in during the first fortnight, rooflights are cut in and sealed the same day, and insulation, plastering and finishes follow.
Add the design and certificate stage beforehand and the full journey from first call to handover is roughly 12 to 16 weeks.
You need around 2.3m or more at the ridge, and that height needs to extend across a decent area of the loft rather than a narrow strip under the ridge line. Bear in mind the new insulated floor and ceiling build-up takes a little of the existing height.
Daniel measures all of this at the free survey and tells you on the spot whether the numbers work, and if they do not, whether a dormer or mansard would create the headroom instead.
Yes, on the right loft. Upper-end Velux builds around £48,000 include a compact shower room, usually positioned near the centre of the roof where headroom is best and above the existing bathroom below to keep the plumbing runs short.
On smaller lofts the space is often better spent on the room itself, and Daniel will give you an honest steer on that at the survey.
Yes, and some clients plan it that way deliberately. The staircase, strengthened floor, insulation and electrics in a Velux conversion are built to the same Building Regulations standard as any other conversion, so nothing is wasted if you add a dormer in a few years.
If you think an upgrade is likely, tell us at the survey and we will position the staircase and services so a future dormer slots in with minimal rework.
Adds the most usable headroom and floor space. The most popular choice for Victorian and Edwardian terraces across South London.
About Dormer conversionsTwo dormers joined in an L over the rear and side return. Adds two rooms, typically a bedroom and a generous bathroom.
About L-Shaped Dormer conversionsA full new storey behind a steep rear wall. The highest spec, the biggest space, often required in conservation areas.
About Mansard conversionsSquares off a sloping side roof to create the volume needed for a proper room, perfect for semi-detached and end-of-terrace homes.
About Hip-to-Gable conversionsVelux conversions come into their own on London's taller-roofed housing stock: the Victorian and Edwardian terraces of Putney, Wandsworth, Hammersmith and Richmond all tend to carry the ridge height they need, and conservation areas that restrict roof extensions will usually accept rooflights.
We build them across the whole of London from our Fulham base.
Tap any area to see what's possible on a house like yours.
Tell us your postcode and a bit about your house.
Daniel will arrange a free home survey to measure your ridge height and confirm whether a Velux conversion is the right call, and if it is, you'll have a fully itemised fixed-price proposal within 7 days of the visit.
If your roof needs a different approach, he'll tell you that too and recommend the right type for your house.
Prefer to talk? Call Daniel on 07414 648 263.
