Building services in Welwyn Garden City
House extensions
- Single-storey extensions
- Double-storey extensions
- Side extensions
- Side return extensions
- Wraparound extensions
- Kitchen extensions
- Orangeries
- Glazed and contemporary extensions
- Porches
Loft conversions
- Dormer loft conversions
- Hip-to-gable loft conversions
- Mansard loft conversions
- Rooflight loft conversions
- Bungalow loft conversions
Garage, basement and barn conversions
New build homes
Renovations and structural work
Design and approvals
Guide prices in Welwyn Garden City
| Project | Guide range (inc VAT) |
|---|---|
| Double-storey extensions | £1,750–£2,650 per m² of floor area (both floors) |
| Dormer loft conversions | £51,000–£72,000 for a typical rear dormer with en-suite |
| Garage conversions | £19,000–£32,000 for a single integral garage |
| House renovations | £950–£1,900 per m² for a medium to full renovation |
| Structural alterations and knock-throughs | £4,750–£10,000 for a typical knock-through with steel beam |
| Porches | £7,000–£17,000 from a 3 m² porch to a small front extension |
We start from a UK-wide guide and adjust it for the East of England, where labour and materials are typically about 6% above average.
Planning permission in Welwyn Garden City
In England a single-storey rear extension is often permitted development: broadly up to 3 metres deep on a semi-detached or terraced house and 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary, and covering no more than half the garden. The larger home extension scheme allows up to 6 or 8 metres if you notify the council first and neighbours have a chance to comment. In conservation areas, National Parks and National Landscapes the larger home extension route, side extensions and cladding are not permitted development. Flats and houses whose rights have been removed need a planning application, and listed buildings need listed building consent.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
About building in Welwyn Garden City
Across the East of England, 1930s and post-war semis, newer estates and rural cottages all feature, each with different extension and loft options.
Welwyn Garden City sits in Hertfordshire, about 6 miles west of Hertford. We cover the whole of Welwyn Garden City, including postcodes AL8. Welwyn Garden City has a population of around 52,000.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions from homeowners in Welwyn Garden City
Is the home visit free?
Yes. The first visit to discuss your project and measure up for a quote is free, with no obligation.
How much does a loft conversion cost in Welwyn Garden City?
A rear dormer loft conversion in Welwyn Garden City typically costs £51,000–£72,000 for a typical rear dormer with en-suite, including VAT.
How much does an extension cost in Welwyn Garden City?
A single-storey extension in Welwyn Garden City typically costs £2,050–£3,050 per m² of floor area, and a double-storey extension £1,750–£2,650 per m² of floor area (both floors), including VAT.
Do you work in Welwyn Garden City?
Yes. We take on extensions, loft conversions, conversions, renovations and new builds across Welwyn Garden City, including postcodes AL8.
Do I need planning permission for an extension in Welwyn Garden City?
In England a single-storey rear extension is often permitted development: broadly up to 3 metres deep on a semi-detached or terraced house and 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary, and covering no more than half the garden. The larger home extension scheme allows up to 6 or 8 metres if you notify the council first and neighbours have a chance to comment. In conservation areas, National Parks and National Landscapes the larger home extension route, side extensions and cladding are not permitted development. Flats and houses whose rights have been removed need a planning application, and listed buildings need listed building consent.