Porch extensions in Marlow: design, approvals and build
If you live in Marlow and want more space without moving, a porch extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in MarlowFrom £4,450 inc VAT
- PlanningUsually permitted development under 3 m²
- Build time2–4 weeks on site
- Postcode districtsSL7

Porch extension prices in Marlow
For Marlow we adjust our national guide rates by ×1.12, the factor we use for South East England. Figures include VAT; your written quote after the survey replaces them.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Small brick or glazed porch, up to 3 m² | £4,450 – £7,300 |
| Standard | Brick porch with tiled roof and composite door | £6,700 – £10,650 |
| Premium | Larger porch with WC or oak frame and premium glazing | £10,050 – £16,800 |
Want a range for your exact size? The guide-price tool takes about a minute.
Extensions in and around Marlow
We cover Marlow and the postcode districts SL7. We also work in nearby High Wycombe (4 miles), Gerrards Cross (9 miles), Amersham (10 miles), Chalfont St Peter (10 miles).
For homes towards Berkshire, Maidenhead is around 4 miles away. The South East has a broad mix of 1930s semis, post-war estates, newer developments and period cottages, and many houses have enough garden for a generous rear extension.
Planning and approvals in Marlow
In England a porch is usually permitted development if its ground floor area is no more than 3 m² measured externally, no part is over 3 m high, and no part is within 2 m of a boundary next to a road.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Included in a typical project
- Front door, glazing and electrics
- Design to suit the house style
- Brick, render or oak frame walls
- Foundations and drainage for rainwater
- Planning check against the porch limits
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Common questions in Marlow
Do I need building regulations approval in Marlow?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Do you cover all of Marlow?
Yes. We cover Marlow and the surrounding parts of Buckinghamshire. Site visits are free and there is no obligation.
Will my neighbours in Marlow be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
How much does a porch cost?
Our guide range is about £4,450 to £16,800 including VAT, depending on size, materials and whether it includes a WC.
Do I need planning permission for a porch?
In England a porch is usually permitted development if its ground floor area is no more than 3 m² (measured externally), no part is higher than 3 m, and no part is within 2 m of a boundary next to a highway. Other nations have similar but separate rules.
Book a free site visit in Marlow
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.