Colchester flat roof extensions, designed and built
A flat roof extension in Colchester starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in ColchesterFrom £22,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsCO1, CO2, CO3, CO4, CO7
What should I budget for a flat roof extension in Colchester?
Prices below are for Colchester, using the East of England factor of ×1.06. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Colchester: £1,860 to £3,550 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £22,000 – £26,500 | £26,000 – £33,500 | £33,000 – £43,000 |
| 4 m × 5 m 20 m² | £37,000 – £43,500 | £43,000 – £55,500 | £55,000 – £71,500 |
| 5 m × 6 m 30 m² | £55,500 – £65,500 | £65,000 – £83,000 | £82,500 – £107,000 |
Try the guide-price tool to see a range for your own size and finish.
Extensions in and around Colchester
Postcode districts we cover around Colchester include CO1, CO2, CO3, CO4, CO7. The same team covers Clacton-on-Sea (13 miles), Witham (13 miles), Maldon (15 miles), Braintree (15 miles), all within easy reach.
Sudbury, in Suffolk, is roughly 13 miles from Colchester and also on our list. Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
Is a flat roof extension right for your house?
- Homeowners who want maximum light from above
- Modern and 1930s onwards houses
- Extensions under first-floor windows where a pitch will not fit
Planning and approvals in Colchester
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
We visit your Colchester home, measure up, talk through what you want and check the planning position.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Your questions about a flat roof extension in Colchester
How long does a flat roof extension take to build in Colchester?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Do you cover all of Colchester?
Yes. We cover Colchester and the surrounding parts of Essex. Site visits are free and there is no obligation.
Who do I contract with for a flat roof extension in Colchester?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I walk on a flat roof extension?
Only for maintenance unless it is designed as a terrace. A roof terrace or balcony needs planning permission and a different structure.
Are flat roof extensions cheaper?
Usually slightly, because there is less roof structure and no tiles. Our guide range is about £1,860 to £3,550 per m² including VAT.
Book a free site visit in Colchester
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.