Welwyn Garden City bungalow extensions, designed and built
Planning a bungalow extension in Welwyn Garden City? We survey the house, work out the planning route, draw the design and build it, so you deal with one team from the first visit to the completion certificate.
- Guide price in Welwyn Garden CityFrom £27,500 inc VAT
- PlanningSingle storey often permitted development
- Build time10–18 weeks on site
- Postcode districtsAL6, AL7, AL8, AL10
Planning and approvals in Welwyn Garden City
In England a single-storey extension to a bungalow follows the normal permitted development limits (3 m or 4 m, or 6 m and 8 m through prior approval). Adding a first floor always needs planning permission.
The planning position for a specific Welwyn Garden City address depends on its history and any designations, which is why we check it at the first visit.
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Working in Welwyn Garden City
Postcode districts we cover around Welwyn Garden City include AL6, AL7, AL8, AL10. Neighbouring towns we cover include Hatfield (3 miles), Hertford (6 miles), St Albans (6 miles), Harpenden (6 miles).
Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
How much does a bungalow extension cost in Welwyn Garden City?
For Welwyn Garden City we adjust our national guide rates by ×1.06, the factor we use for East of England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Welwyn Garden City: £1,860 to £3,600 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 5 m 15 m² | £27,500 – £33,500 | £32,500 – £42,500 | £41,000 – £54,500 |
| 4 m × 6 m 24 m² | £44,500 – £53,500 | £52,000 – £67,500 | £66,000 – £86,500 |
| L-shape 35 m² | £64,500 – £78,000 | £76,000 – £98,500 | £96,000 – £126,500 |
Try the guide-price tool to see a range for your own size and finish.
What we take care of
- Planning application where needed
- Structural survey before any upward extension
- Roof designs that tie into the existing hipped or gable roof
- Single-storey extension options assessed first
- Level thresholds and accessible layouts
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
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
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 bungalow extension in Welwyn Garden City
Will my neighbours in Welwyn Garden City 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.
Do you cover all of Welwyn Garden City?
Yes. We cover Welwyn Garden City and the surrounding parts of Hertfordshire. Site visits are free and there is no obligation.
Do I need building regulations approval in Welwyn Garden City?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I extend a bungalow without planning permission?
In England a single-storey rear extension to a bungalow follows the same permitted development limits as a house: 3 m or 4 m, or up to 6 m or 8 m through prior approval. Adding a storey always needs planning permission.
Is it better to extend sideways or upwards?
Sideways and rearwards is usually simpler, cheaper and keeps single-level living. Upwards saves garden but means stairs, more structure and planning permission.
Book a free site visit in Welwyn Garden City
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.