Side extensions for homes in Hertford
We design and build side extensions for houses in Hertford, with a written price once the survey and design are done and one point of contact throughout.
- Guide price in HertfordFrom £23,000 inc VAT
- PlanningSingle storey can be permitted development
- Build time10–18 weeks on site
- Postcode districtsSG13, SG14
Guide prices for Hertford
Prices below are for Hertford, 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 Hertford: £1,860 to £3,600 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 5 m 12 m² | £23,000 – £28,000 | £26,000 – £34,000 | £33,000 – £43,500 |
| 3 m × 6 m 18 m² | £33,000 – £40,500 | £39,000 – £51,000 | £49,500 – £65,000 |
| 3 m × 8 m 24 m² | £44,500 – £53,500 | £52,000 – £67,500 | £66,000 – £86,500 |
For a figure based on your own dimensions, use our guide-price tool.
Planning and approvals in Hertford
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
Who a side extension suits
- Houses where the rear garden is small
- Homes needing a utility, study or ground-floor bedroom
- Detached and semi-detached houses with side land
Covering Hertford
Across SG13, SG14, we can visit, measure and advise. The same team covers Hoddesdon (4 miles), Welwyn Garden City (6 miles), Hatfield (7 miles), Cheshunt (7 miles), all within easy reach.
Just over the Essex border, Waltham Abbey is about 8 miles away. Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
Our process, step by step
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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.
Side extension questions answered
Do you cover all of Hertford?
Yes. We cover Hertford and the surrounding parts of Hertfordshire. Site visits are free and there is no obligation.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Hertford, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does a side extension take to build in Hertford?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
How much does a side extension cost?
Our guide range is about £1,860 to £3,600 per m² including VAT, depending on specification, so a standard 18 m² single-storey side extension lands around £39,000 to £51,000 in Hertford.
How close to the boundary can I build?
It depends on height. In England, within 2 m of a boundary the eaves must not exceed 3 m under permitted development. Building on the boundary is possible but brings party wall and maintenance access issues we plan for.
Book a free site visit in Hertford
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.