Portslade, East Sussex
Glazed rear extension in Portslade
Glazed rear extension in Portslade: full-height glass, slim frames and big rooflights for the most open rear room. We measure the house, show you what the rules allow, price it in writing and build it.
We cover Portslade (BN1, BN3 and BN41) as part of our East Sussex work. If your garden in Portslade 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 Portslade?
In Portslade, our guide for a glazed rear extension is £3,140–£5,380 per square metre including VAT for a standard specification. 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 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a glazed rear extension in Portslade?
Here is how the rules in England apply to a glazed rear extension in Portslade.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is 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. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Portslade like to extend?
Commuter semis and detached houses make up much of Portslade, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How a glazed rear extension in Portslade comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
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.
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.
Glazed rear extensions near Portslade
We also build glazed and glass-box rear extensions in nearby Hove (2.3 miles) and Shoreham-by-Sea (2.6 miles).
- Glazed rear extension in Hove
- Glazed rear extension in Shoreham-by-Sea
- Glazed rear extension in Brighton
- Glazed rear extension in Lancing
- Glazed rear extension in Hurstpierpoint
Other work in Portslade:
FAQ
Glazed rear extension questions in Portslade
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
How much does a glazed rear extension cost in Portslade?
As a guide, £3,140–£5,380 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £37,500–£64,500 at that rate. Your written price follows the survey.
Is there a limit on how much glass I can have?
In England the simple rule is 25% of the floor area plus openings removed; more is allowed with a calculation showing the house still meets Part L.
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.
What postcode areas do you cover around Portslade?
Including BN1, BN3 and BN41, and the surrounding East Sussex area.
Do you handle building control in Portslade?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.