Builders in north London, with our own team on site
Promaester is a north London building company. We convert lofts, build extensions and refurbish houses with our own team of four to five trades, and you pay weekly for the work done, with no deposit.
- No deposit
- Pay weekly for work done
- Build schedule you can check daily
Recent jobs in north London
Three of our north London jobs, photographed by us. Click through for the full set, from the house as it was to the finished rooms.
What we build
We build three kinds of job in north London. Rear dormer loft conversions on terraces and semis, which add a bedroom and a shower room without moving house. Single-storey rear and side return extensions, usually for a bigger kitchen and dining room. And refurbishments, from a refresh to a full rewire and replaster.
The people who price the job are the people who build it. We arrange the architect and the structural engineer if you need them, and we book and attend every Building Control inspection.
Planning in each borough
The national permitted development rules are the same in every north London borough. What changes is how much of each borough is protected. Enfield has 22 conservation areas, Barnet has 16 and Haringey has 29, and inside a conservation area the permitted development rights for roofs don't apply and extensions are far more limited.
We've written up the rules borough by borough, with the council's own sources, so you can check your road before paying for drawings.
What it costs in north London
Our recent north London rear dormer loft quotes, from 2026, came in at about £72,000 to £85,000 including VAT, for a bedroom with a shower room or en-suite. Our recent single-storey extension quotes came in at about £56,000 to £90,000 including VAT, and in north London expect to be nearer the top of that.
Those are rounded ranges from real quotes, not a price for your house. You get a fixed, itemised quote after we've surveyed it.
Where we work
Edmonton, Enfield, Barnet, Southgate, Finchley, Tottenham, Wood Green, Muswell Hill, Walthamstow, Chingford, Islington, Camden, Hackney, Haringey. If you’re just outside these, send us your postcode and we’ll tell you whether we can take it on.
From first visit to finished room
Five stages. We manage each one and tell you what’s needed from you before it starts.
Survey
We visit, measure, check the structure and tell you what's realistic for your house.
Drawings and calculations
Architect plans and structural calculations, ready for Building Control.
Approvals
Lawful development certificate or planning, Building Control and party wall notices.
Build
Our own team on site, Monday to Friday, with a schedule you can check every day.
Sign-off
Building Control completion certificate and electrical certificates handed to you.
No deposit. You pay for progress, every Friday.
You never pay ahead of the work. Each Friday you pay for what was built that week, and only if the job has moved forward.
- A live build scheduleShared with you as a Google Sheet and updated daily, including Building Control inspection dates.
- Predictable site hoursMonday to Friday, 8am to 5pm, with a team of four to five on site.
- A considerate siteNo radios and no smoking, at any point in the job.
Questions about building in north London
Edmonton, Enfield, Barnet, Southgate, Finchley, Tottenham, Wood Green, Muswell Hill, Walthamstow, Chingford, Islington, Camden, Hackney and Haringey. If you're near the edge of that, send us your postcode and we'll tell you.
No. We run our own team of four to five trades on site, so the people who price your job are the people who build it.
Yes. We arrange the architect and the structural engineer if you don't have them, tell you at the survey whether you're likely to need planning, and book and attend every Building Control inspection.
As a guide, a rear dormer loft is 6 to 8 weeks on site and a single-storey rear extension 12 to 16 weeks. That's work on site only, not drawings or approvals.
No. There's no deposit. We invoice every Friday for the work done that week, so you pay weekly in arrears and never pay for work that hasn't happened yet.
Book a survey
We’ll visit, measure up and tell you what’s realistic for your house, along with a guide price for each option worth considering.