GSM Builders Ltd are builders in Ruislip and across the HA4 area including Ruislip Manor, Ruislip Gardens, South Ruislip, Eastcote and Ickenham. As a Hillingdon-based company (our yard is in Hayes, about 15 minutes down the A437) we know the local housing, the local planning department and the local suppliers.
Metroland houses and what they can become
Ruislip is classic 1930s “Metroland”: wide tree-lined roads of semi-detached and detached houses with hipped roofs, bay windows and long gardens, built when the Metropolitan and Piccadilly lines arrived. Ninety years on, most families want more space than the original layout gives them, and these houses are among the easiest in London to extend.
The projects we are asked for most in Ruislip are hip-to-gable loft conversions with a rear dormer (often adding a large bedroom, en-suite and eaves storage), wrap-around extensions that combine a rear and side extension into one open-plan kitchen, dining and family room, and double-storey side extensions that add a bedroom above a new utility or garage space. We also carry out a lot of full refurbishments for buyers modernising a house that has not been touched since the 1970s.
Planning in Ruislip and Hillingdon
Planning is handled by the London Borough of Hillingdon. Ruislip Village, Eastcote Village and parts of Ickenham are conservation areas, and Ruislip Woods and the Lido sit within the green belt, so a small number of streets have tighter rules. Elsewhere, single-storey rear extensions up to 3 m (or 6 m with prior approval) and loft conversions up to 50 m³ on a semi are normally permitted development. Hillingdon also allows householders to apply for a Lawful Development Certificate, which we recommend for any loft or extension so you have paperwork proving the work was lawful when you sell.
Building services we offer in Ruislip
- House extensions, single-storey rear, side-return, wrap-around and double-storey
- Loft conversions. Velux, rear dormer, hip-to-gable and L-shaped
- Full property refurbishment and renovations
- Kitchen fitting and kitchen renovation
- Bathroom renovation and wall tiling
- Roofing, plastering, flooring and painting & decorating
- 24/7 emergency call-outs, plumbing, electrics, glazing and boarding-up
Why choose GSM Builders Ltd in Ruislip?
- Genuinely local. Our base at Leven Way, Hayes UB3 is about 15 minutes by road from Ruislip, so site visits, quotes and snagging calls are quick and easy.
- One team from start to finish. Design input, structural calculations, Building Control liaison, all trades and decoration under one contract.
- Building Control approved work. Every structural project is signed off with completion certificates you will need when you sell or remortgage.
- Clear written quotes. Itemised pricing, agreed payment stages and no hidden extras.
- Fully insured with public liability cover and a 12-month workmanship warranty.
Examples of our work in the Ruislip area
- Hip-to-gable loft conversion with rear dormer on a 1930s semi in Ruislip Manor
- Wrap-around kitchen extension with vaulted ceiling and sliding doors in Eastcote
- Double-storey side extension adding a fourth bedroom in South Ruislip
- Full house renovation including rewire, new boiler and two bathrooms in Ickenham
What building work costs in Ruislip (2026)
These are the 2026 ranges we quote for Ruislip (HA4), excluding VAT. They assume a standard specification and reasonable access; the cost calculator gives a figure for your own project, and a free site survey gives you a fixed written price.
| Project | 2026 price (excl. VAT) | Time on site |
|---|---|---|
| Single-storey rear extension (3 m) | £48,000 to £68,000 | 8 to 10 weeks |
| Side-return extension | £45,000 to £65,000 | 8 to 10 weeks |
| Wrap-around extension | £65,000 to £95,000 | 10 to 14 weeks |
| Rear dormer loft conversion | £38,000 to £48,000 | 6 to 8 weeks |
| Hip-to-gable loft with en-suite | £55,000 to £85,000 | 8 to 10 weeks |
| Whole-house refurbishment (3-bed) | £70,000 to £150,000 | 10 to 18 weeks |
| Kitchen fitting (supply & fit) | £12,000 to £30,000 | 2 to 4 weeks |
| Bathroom refit | £8,000 to £20,000 | 2 to 3 weeks |
Drawings, structural calculations and Building Control fees add £2,500 to £4,500. Where planning is needed, Hillingdon Council charges £548 for a householder application or £249 for prior approval (fees from 1 April 2026). Our planning guide explains which route applies, and the loft conversion comparison covers which loft type suits your roof.
Frequently asked questions
Do I need planning permission for an extension in Ruislip?
Ruislip is in the London Borough of Hillingdon. Outside the Ruislip Village conservation area, a single-storey rear extension up to 3 m on a semi (4 m on a detached house) is normally permitted development, and 3 to 6 m (4 to 8 m detached) needs prior approval at £249. Inside the conservation area a householder application at £548 is usually required.
How deep can I extend on a Ruislip plot?
Interwar Ruislip plots are often deep enough for a 4 m rear extension and still leave a usable garden. Detached houses get 4 m under permitted development and up to 8 m with prior approval, so it is worth checking the plot before settling for 3 m.
How quickly can you get to Ruislip?
Our yard is on Leven Way in Hayes, about 15 minutes from Ruislip, so site visits, deliveries and snagging calls are straightforward. There is no London-wide travel premium in our pricing.
Do you handle Building Control in Ruislip?
Yes. Every extension, loft conversion and structural alteration needs Building Regulations approval and a completion certificate regardless of planning. We make the application, book the inspections and hand you the certificate at the end, you will need it when you sell.
Are you insured and do you give a warranty?
Yes, public and employer’s liability insurance, an itemised written quote before anything starts, staged payments against completed work and a 12-month workmanship warranty in writing on every contract.
Nearby areas we also cover
Hillingdon · Uxbridge · Harrow · Greenford & Northolt · West London
Talk to local Ruislip builders
For a free, no-obligation quote on a loft conversion, extension or refurbishment in Ruislip, get in touch and we will arrange a visit.