Welwyn Garden City, Hertfordshire
Side return extension in Welwyn Garden City
Thinking about a side return extension in Welwyn Garden City? Infilling the narrow passage beside a Victorian or Edwardian back addition. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Welwyn Garden City and its postcode districts AL7 and AL8 are part of our Hertfordshire coverage. In Welwyn Garden City we check the boundary line and the neighbour's gutter before drawing a side return, because a few centimetres decide whether the wall goes on or beside the boundary.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a side return extension cost in Welwyn Garden City?
Guide prices for a side return extension in Welwyn Garden City start from our East of England rate of £2,440–£4,030 per square metre, including VAT. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.
| Size | Guide price inc VAT |
|---|---|
| 2 m wide × 6 m deep (12 m²) | £29,500–£48,500 |
| 2.5 m wide × 7 m deep (17.5 m²) | £42,500–£70,500 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a side return extension in Welwyn Garden City?
Planning for a side return extension in Welwyn Garden City follows the English householder rules.
In England the side part of a side return or wraparound must meet the side-extension rules (one storey, under 4 metres high, no more than half the width of the original house), and those rights do not apply on designated land. Because a wraparound combines a side and a rear extension, many need householder planning permission.
Because rear extensions often sit on or near the boundary, the Party Wall etc. Act 1996 usually applies in England. Notices go out one or two months before work depending on the type of work, and a surveyor's award is only needed if a neighbour does not consent.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Welwyn Garden City like to extend?
Welwyn Garden City mixes Victorian terraces with 1930s semis, so both side returns and full-width kitchen extensions suit houses here.
How a side return extension in Welwyn Garden City comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Side return extensions near Welwyn Garden City
Neighbouring places we cover include Hatfield (2.8 miles) and Codicote (3.6 miles).
- Side return extension in Hatfield
- Side return extension in Codicote
- Side return extension in Hertford
- Side return extension in St Albans
- Side return extension in Harpenden
Other work in Welwyn Garden City:
FAQ
Side return extension questions in Welwyn Garden City
Can you match the brick or stone on my Welwyn Garden City house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.
Glass roof or solid roof with rooflights?
A glass roof gives the most light; a solid roof with long rooflights is warmer and quieter in rain. Both work.
What postcode areas do you cover around Welwyn Garden City?
Including AL7 and AL8, and the surrounding Hertfordshire area.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
How long does a rear extension take to build in Welwyn Garden City?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.