Dartford, Kent
Glazed rear extension in Dartford
Full-height glass, slim frames and big rooflights for the most open rear room. If you live in Dartford and want to know what a glazed rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
We cover Dartford (DA1) as part of our Kent work. If your garden in Dartford faces south, expect us to talk about overhangs and solar-control glass before frame colours.
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 glazed rear extension cost in Dartford?
Guide prices for a glazed rear extension in Dartford start from our South East England rate of £3,140–£5,380 per square metre, including VAT. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £37,500–£64,500 |
| 4 m wide × 6 m deep (24 m²) | £75,500–£129,000 |
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 glazed rear extension in Dartford?
Planning for a glazed rear extension in Dartford follows the English householder rules.
English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.
New fabric must meet Approved Document L (2021 edition incorporating 2023 amendments): walls 0.18, roof 0.15 and floor 0.18 W/m²K, windows 1.4 W/m²K or Band B. Under the simple route, new windows, doors and rooflights should not exceed 25% of the extension floor area plus any openings removed; more glass is possible with a whole-house calculation.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Dartford like to extend?
Commuter semis and detached houses make up much of Dartford, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How a glazed rear extension in Dartford comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Glazed rear extensions near Dartford
Neighbouring places we cover include Bexley (2.8 miles) and Swanley (3.8 miles).
- Glazed rear extension in Bexley
- Glazed rear extension in Swanley
- Glazed rear extension in Belvedere
- Glazed rear extension in Swanscombe
- Glazed rear extension in Chafford Hundred
Other work in Dartford:
FAQ
Glazed rear extension questions in Dartford
What postcode areas do you cover around Dartford?
Including DA1, and the surrounding Kent area.
Do I need planning permission for a rear extension in Dartford?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
Does glass need planning permission?
The same rules apply as any rear extension; glass does not change the depth or height limits.
How long does a rear extension take to build in Dartford?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Can you match the brick or stone on my Dartford house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.