Hemel Hempstead, Hertfordshire
Glazed rear extension in Hemel Hempstead
Glazed rear extension in Hemel Hempstead: 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 Hemel Hempstead (HP1, HP2 and HP3) as part of our Hertfordshire work. A wide sliding door with one long rooflight, rather than a fully glazed roof, keeps a glass-led extension usable in summer.
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 Hemel Hempstead?
In Hemel Hempstead, our guide for a glazed rear extension is £2,970–£5,090 per square metre including VAT for a standard specification. 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 |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £35,500–£61,000 |
| 4 m wide × 6 m deep (24 m²) | £71,000–£122,000 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a glazed rear extension in Hemel Hempstead?
Whether your glazed rear extension in Hemel Hempstead needs a planning application depends on its size, your house and any local restrictions.
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 Hemel Hempstead like to extend?
Hemel Hempstead mixes Victorian terraces with 1930s semis, so both side returns and full-width kitchen extensions suit houses here.
How a glazed rear extension in Hemel Hempstead 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.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
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 Hemel Hempstead
Close by, we work in Abbots Langley, about 3.6 miles away, and Berkhamsted, about 5.0 miles away.
- Glazed rear extension in Abbots Langley
- Glazed rear extension in Berkhamsted
- Glazed rear extension in St Albans
- Glazed rear extension in North Watford
- Glazed rear extension in Harpenden
Other work in Hemel Hempstead:
FAQ
Glazed rear extension questions in Hemel Hempstead
How long does a rear extension take to build in Hemel Hempstead?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
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.
Will a glass extension be too hot?
Not if it is designed for its orientation, with solar-control glass, shading and ventilation.
Can you match the brick or stone on my Hemel Hempstead house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
Do you handle building control in Hemel Hempstead?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Is the site visit in Hemel Hempstead free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.