Merseyside
Rear extensions in Rainhill
We design and build rear extensions for homes in Rainhill, Merseyside, from single-storey kitchen-diners across the back of the house to two-storey extensions that add a bedroom above.
Rainhill is in Merseyside, with postcode districts including L35. The nearest places we also cover are Whiston (1.0 miles) and Prescot (1.7 miles).
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
Rear extensions we build in Rainhill
- Single-storey rear extensions
- Two-storey rear extensions
- Kitchen-diner rear extensions
- Side return extensions
- Wraparound extensions
- Glazed and glass-box rear extensions
- Rear extensions for terraced houses
- Rear extensions for semi-detached houses
- Rear extensions for bungalows
- Rear extension plans and planning applications
Also available across Merseyside:
- Rear extensions for detached houses
- Flat-roof rear extensions
- Pitched and lean-to roof rear extensions
- Knocking through to a rear extension
- Roof lanterns and rooflights for rear extensions
- Permitted development rear extensions
- Larger home extension prior approval (England)
- Building Regulations for rear extensions
Rear extension prices in Rainhill
North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Example | Guide inc VAT |
|---|---|
| Single-storey, 3 m × 4 m (12 m²) | £21,500–£35,000 |
| Single-storey, 4 m × 6 m (24 m²) | £43,000–£70,000 |
| Two-storey, 3 m × 5 m footprint (30 m²) | £51,000–£76,000 |
| Side return, about 14 m² | £30,500–£50,000 |
| Wraparound, about 25 m² | £51,500–£84,500 |
What are homes in Rainhill like to extend?
Stone and brick terraces are common around Rainhill. Where houses back onto a ginnel or alley, deliveries can come in from the rear, which makes the build tidier.
Planning rules for Rainhill
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.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
Every rear extension in England needs Building Regulations approval, whether or not planning is needed. You can use the council's building control service or a registered building control approver, by full plans (checked before work, usually within five weeks) or a building notice, and you get a completion certificate at the end.
Nearby towns
FAQ
Questions people ask
How much is a rear extension in Rainhill?
A 3 m × 4 m single-storey rear extension is about £21,500–£35,000 including VAT at our North West England guide rates; the written price follows a survey.
Do I need planning permission in Rainhill?
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.
Is the site visit in Rainhill free?
Yes, with no obligation.
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.