Area guide · N14
House Extensions in Southgate (N14)
Planning a house extension in Southgate? We design, gain planning permission and build extensions and loft conversions across N14, from the Edwardian streets around Southgate Green to the 1930s avenues towards Oakwood. Most single-storey rear extensions here cost £45,000–£90,000 to build, applications go to Enfield Council, and the most-approved route in N14 right now is the prior-approval householder extension — the fast track to a 6m rear on a Southgate semi. Have us round for a free site visit and we'll map your options street by street.
Live planning data
What Enfield Council is actually approving right now
We track every residential planning decision across North London — so you can see what Enfield is saying yes to before you spend a penny on drawings. In the most recent decision window, 13 N14 schemes were approved, within 113 residential approvals borough-wide. These are real examples from Southgate's postcode:
- 78 The Vale, N14 — householder extension approved through the prior-approval (larger home) route
- 42 Chestnut Close, N14 — householder extension approved through the prior-approval route
- 6 Elmbank, N14 — householder extension and alterations (approved)
The pattern is clear: the prior-approval route is doing the heavy lifting in N14. Two of the three examples above used it — the process that takes a semi from the standard 3m rear extension to a full 6m (8m on detached houses) by consulting the neighbours rather than running a full application. On Southgate's deeper plots it's very often the smartest opening move, with a loft conversion as the natural second phase. The third example matters too: a conventional householder application at Elmbank, decided without drama. Between the streamlined route and the standard one, N14 owners currently have two well-oiled paths to a bigger house.
Source: Enfield Council's published decision lists. We share these to show the direction of local approvals — they aren't our schemes, and every application is judged on its own facts.
Local knowledge
Southgate's housing stock — and what works on each
Southgate announces itself with one of London's finest buildings — Charles Holden's circular 1933 station, listed at Grade II*. The houses around it split into three distinct markets, each with its own best move.
The Edwardian streets around Southgate Green. Handsome bay-fronted houses on mature roads. The classic plays here: a side-return extension (£35,000–£65,000) reclaiming the dead alley beside the kitchen, a wrap-around (£70,000–£140,000) for a complete ground-floor rethink, and a loft conversion with rear dormer making use of the generous Edwardian roof. Party wall agreements feature on the tighter plots; we run that process for you.
The 1930s belt towards Oakwood. Hipped-roof semis on wide avenues — the same stock driving N14's approvals list. The 6m prior-approval rear extension (£45,000–£90,000) and the hip-to-gable loft with rear dormer (£55,000–£90,000) are the two highest-value moves, and the recent decisions show the route working in practice. The quiet bargain on these avenues is the garage conversion (£18,000–£35,000) — many of the 1930s houses have an attached garage storing little but paint, and converting one adds a study or playroom in four to six weeks.
The Lakes Estate, between Fox Lane and Bourne Hill. Southgate's celebrated Edwardian enclave, straddling the border with Palmers Green — and a conservation area, where permitted development rights are restricted. Extensions still happen here regularly; they simply go through as full applications with proper care on materials, rooflines and detailing. We treat that as a design brief, not a barrier.
Every street is different. That's the point.
We design to Southgate's stock and to what the council demonstrably approves — not to a template. A free site visit tells you what your house can take.
Get my free estimateHonest numbers
What a house extension costs in Southgate in 2026
These are realistic all-in build ranges for Southgate — labour and materials to a good standard, excluding VAT, professional fees and kitchen fit-out:
| Extension type | Typical Southgate cost | On-site time | Usual planning route |
|---|---|---|---|
| Side-return extension | £35,000 – £65,000 | 2–3 months | Often permitted development |
| Single-storey rear | £45,000 – £90,000 | 3–4 months | Often permitted development |
| Kitchen extension (incl. mid-range kitchen) | £55,000 – £110,000 | 3–4 months | Often permitted development |
| Hip-to-gable loft + rear dormer | £55,000 – £90,000 | 6–10 weeks | Usually permitted development |
| Wrap-around extension | £70,000 – £140,000 | 4–6 months | Full application |
| Double-storey rear | £75,000 – £160,000 | 5–7 months | Full application |
| Garage conversion | £18,000 – £35,000 | 4–6 weeks | Usually permitted development |
As a rule of thumb, Southgate builds at £2,800–£4,200 per square metre — standard North London rates. Multiply that out and a 20m² rear scheme sits in the £60,000–£80,000 bracket for the build. Spec is the biggest lever — glazing, flooring and the kitchen itself move the total far more than the postcode does. After the free site visit we put everything in writing as a fixed, itemised quote: what's printed there is what you'll actually pay, to the penny.
Permissions, handled
Planning permission in Southgate — what you need to know
Most Southgate extensions don't need a full planning application. On a semi or terrace, permitted development lets a rear extension run 3m deep without an application; a detached house gets 4m. The larger home prior-approval route then lifts those limits to 6m and 8m — the same path 78 The Vale and 42 Chestnut Close took in the recent decisions. Loft conversions enjoy a generous volume allowance.
The Lakes Estate is the exception. On the Edwardian roads between Fox Lane and Bourne Hill, permitted development rights are restricted and schemes are judged on conservation criteria — materials, proportions and roof forms matter. Elsewhere in Southgate, we check your address against Enfield's conservation map as standard before designing.
Timing: count on roughly eight weeks for Enfield to determine a standard householder application; prior-approval cases often conclude sooner. Allow a further 4–8 weeks before submission for design and drawings — worth building into any timeline that's supposed to end with a finished kitchen by Christmas.
Party walls: semis and terraces dominate Southgate, so the Party Wall Act applies to most projects — budget £1,000–£2,500 per affected neighbour where surveyors are appointed, and open the conversation early. We serve the notices as part of the job.
Paperwork that pays: for permitted development projects we secure a Lawful Development Certificate, so your extension stands up to any scrutiny when you sell.
How it works
How it works
- Free site visit — we come to your Southgate house, hear what you're hoping for, and give you an honest read on feasibility, budget and the right planning route.
- Design & drawings — plans drawn to scale plus 3D visuals, designed around your home and the rhythms of family life inside it.
- Planning, handled — every form, drawing and document goes to Enfield Council under our management, right through to the decision.
- Fixed-price build — our vetted North London team builds it out, secures building control sign-off and hands over a tidy finished space.
Our work
Recent work near Southgate
Our build team's recent North London projects include a full house transformation taking a family home from 120m² to 360m², a 55m² garden room with kitchen and bathroom, and an Edwardian conversion in Finchley. Tell us your plans at the site visit and we'll walk you through the nearest equivalents.
Questions, answered
Southgate extension FAQs
What will an extension cost me in Southgate?
£45,000–£90,000 covers most single-storey rear builds; lofts run £55,000–£90,000 and double-storey schemes £75,000–£160,000, all excluding VAT and fees. N14 builds at standard North London rates of £2,800–£4,200/m², and we quote fixed after a free site visit.
I'm on the Lakes Estate — can I still extend?
Yes. Conservation status restricts permitted development, so your scheme goes in as a full application judged on design quality — sympathetic materials, correct proportions, considered rooflines. Well-mannered schemes do get approved; ours are designed that way from the first sketch.
What exactly is a prior-approval extension?
A streamlined route for larger single-storey rears — up to 6m on a semi, 8m on a detached house — where Enfield consults your neighbours rather than assessing a full application. It's currently the most-used route in N14, including the recent approvals at 78 The Vale and 42 Chestnut Close.
Does the listed station change anything for my house?
No — the Grade II* listing protects Holden's station building itself, not the surrounding housing. Your project is governed by normal householder rules unless your own street carries a designation, which we check against the council's conservation map before designing.
How long does Enfield take to decide?
Around eight weeks for a standard householder application — and the borough is approving at volume, with 113 residential schemes passed in a recent two-week window, 13 of them in N14.
Which extension adds most value to an Edwardian house near Southgate Green?
Usually the side-return or wrap-around — turning a narrow galley kitchen into a full-width kitchen-diner transforms how these houses live — with a rear-dormer loft adding a bedroom without losing garden. We'll prioritise by value at the site visit.
Nearby areas we cover
What clients say
Rated 5.0 on Google
“Used The Extension Company for a loft conversion on our semi detached in Barnet and couldn't be happier. They explained what was possible at the first visit, sorted the planning side, and gave a fixed price with no surprises at the end.…” read the full review
“Really impressed with the entire project. The side extension and conservatory have been finished to a very high standard and the team made the process straight forward and stress-free. It’s transformed the space and added so much value, would definitely recommend.”
“Brilliant experience with the extension company, transparent from the word go. Completed a double story extension for me and I couldn’t be more pleased. Thank you”
“I got the extension company to do a bathroom refurb for us a January they done a great job they managed to fit in a large shower as well as a bath”
Reviews shown word for word from our Google profile. Read all 8 reviews on Google
Free site visit
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Free site visit anywhere in Southgate, honest feasibility advice and a fixed, itemised price — design, planning and build handled end to end by the Pine Grove team.
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