An oak-framed garage, porch or garden room is one of the most common building projects around Surrey's villages, and one of the easiest to get wrong. Prices range widely, guarantees cover different things, and the planning rules are stricter across much of the county than many people expect.
This guide sets out the rules first, then five firms that design and build in Surrey. Everything below comes from the Planning Portal or the firms' own websites, checked in October 2026. Prices and terms change, so confirm them when you ask for a quote.
Do you need planning permission?
Porches: adding a porch to an outside door is usually permitted development, so it needs no planning application, as long as its ground floor area is no more than 3 square metres, no part is more than 3 metres high, and no part is within 2 metres of a boundary that faces a road.
Garages and garden buildings: a detached single-storey building can also be permitted development, within limits. The eaves can be no higher than 2.5 metres, and the overall height no more than 4 metres with a dual-pitched roof or 3 metres otherwise, dropping to 2.5 metres if it is within 2 metres of a boundary. It cannot sit in front of the house, and outbuildings cannot cover more than half the land around the original house. It must be used for something incidental to the house, not as a separate home.
Much of Surrey has stricter rules. In the Surrey Hills National Landscape, conservation areas and similar designated land, an outbuilding at the side of the house needs planning permission, and buildings more than 20 metres from the house are limited to 10 square metres in total. Any outbuilding in the grounds of a listed building needs permission. Check with your council before you commit.
Building regulations are a separate question. A detached garage under 15 square metres normally doesn't need approval, nor does one of 15 to 30 square metres if it is at least a metre from any boundary or built largely of non-combustible materials. A garage attached to the house normally does. A ground-level porch under 30 square metres is normally exempt, as long as the front door between the house and the porch stays in place.
Green oak, and why it moves
Most frames are made from green oak, which is freshly sawn rather than dried. It shrinks across the grain as it dries, so splits and cracks appear, and Crown Oak Buildings notes that these are natural and do not affect the structure. Eavoak says most of the shrinkage happens in the first two years. Seasoned, air-dried oak is more stable and more expensive, and Eavoak uses it where high-specification glazing is fitted. Left untreated, oak weathers to a silvery grey.
Five firms that build in Surrey
01
Arbour Bespoke
Farnham, Surrey
A Farnham carpentry firm that designs and builds oak structures, and will work alongside your architect or garden designer. Its recent projects include work in Farnham, Leatherhead and Grayshott.
It does not publish prices or a guarantee, so ask about both when you request a quote.
- Builds
- Oak garages (including rooms above), car ports, garden rooms, porches, outdoor kitchens
- Area
- Surrey, Hampshire and West Sussex
- Contact
- 01252 710518
02
Eavoak
Oakhanger, on the Surrey–Hampshire border
Formerly Rookery Barns, and trading since 1998, with its registered office in Farnham and its workshop at Oakhanger, just over the Hampshire border. It works mainly in Surrey, Hampshire and Sussex.
Eavoak only does complete design-and-build projects, including the planning application and building regulations package; it doesn't sell frames on their own. It gives guide prices for its standard garages on request, and says the design and planning stage alone takes eight to twelve weeks.
- Builds
- Garages, garages with rooms above, garden rooms, annexes, pool houses, garden barns
- Guarantee
- 10 years on structure and foundations (excludes shrinkage and cracking)
- Contact
- 01420 488870
03
Sussex Oak Structures
Faygate, near Horsham
A framing yard just over the West Sussex border that covers Sussex, Surrey and Kent, with recent work at St George's Hill in Weybridge. It builds everything from porches to whole houses, and handles planning applications.
It is unusually open about money, publishing 2026 price ranges for garages and garden rooms, and it gives a ten-year insurance-backed structural guarantee. Its pages differ on whether it sells frames on their own, so ask if you want to self-build.
- Example price
- Two-bay garage with a room above: frame only £40,000–£55,000; turnkey £95,000–£150,000 (its 2026 figures)
- Lead times
- Double garage 8–12 weeks from sign-off; garden room 10–16 weeks from survey
- Contact
- 01293 851287
04
Crown Oak Buildings
Edenbridge, on the Kent–Surrey border
Based on the Kent, Surrey and Sussex border, Crown Oak supplies and fits in Surrey and the neighbouring counties, and sends self-build kits further afield, with numbered joints and the engineer's calculations included.
It publishes example porch prices and has online designers for porches and garages, which makes it a good place to get a feel for costs before talking to anyone.
- Example price
- Open porch 1.8m × 1.2m: kit £2,640 plus £1,320 fitting; clay roof tiles £2,200 (VAT not stated)
- Warranty
- Materials free from defects for 5 years from completion
- Contact
- 01732 866910
05
English Heritage Buildings
Woods Corner, East Sussex
Further away, in East Sussex, but it delivers nationwide and has a page for Surrey. Its online tool lets you design a frame and get an instant quote including delivery, and it says the quoted price includes site-specific structural calculations.
It states it holds BM TRADA Q-Mark certification, which is independently audited. Ask whether it can also put the frame up for you in Surrey.
- Builds
- Garages, garden rooms, extensions
- Guarantee
- 10-year frame guarantee
- Contact
- 01424 838643
Before you sign
Ask exactly what the guarantee covers: the firms above range from five years on materials to ten-year structural guarantees, and some exclude the shrinkage and splitting that green oak always shows. Check whether quoted prices include VAT, foundations, roofing and fitting. Ask to see a finished project near you. And allow for planning time on top of any build time a firm quotes.
If you would like an introduction to one of the makers in our directory, the Private Desk can pass your brief to them.