Builders in London

GS Renovation is a London building firm run by Abdelaaziz Saaid, who has spent more than 30 years on the tools and on site in London homes. The limited company, GS Renovation Ltd, was incorporated in 2023 to put that long-running trade on a formal footing, and it works across London and the surrounding counties from a registered office in Potters Bar. We are builders in the ordinary sense of the word: one accountable team that takes on the whole job, from a single knocked-through wall to a full house refurbishment, rather than a broker passing your project to whoever is free.

Most people arrive at this page because they need building work done and do not yet know what to call it. That is normal. The list below is the honest scope of what we take on, and just as importantly what we do not.

What our London builders take on

We are a general building contractor with a structural specialism. The structural side, steel beams and wall removals, is the part most builders subcontract out, and it is the part we do ourselves. Everything else on a domestic project is carried out by our own team or by trades we have used for years and stand behind.

• Full house refurbishments, including rewiring, replumbing, heating, plastering and decoration
• Kitchen and bathroom installation, from design through to the final seal
• Steel beam (RSJ) installation, load-bearing wall removal and knock-throughs
• Chimney breast removal with the stack above properly supported
• Single and double storey rear and side return extensions
• Structural openings, new joists and supported alterations to existing walls
• Plastering, joinery, flooring, tiling, painting and making good
• Electrical and plumbing first and second fix, with new circuits certified by a registered electrician under Part P or notified to building control

What we are not is a firm of designers. We do not draw your planning application and we do not design your structure. On any job that touches structure we appoint an independent structural engineer, build to their calculations, and put the work in front of building control for inspection. That separation is deliberate. The person specifying the steel should not be the person selling you the steel.

How to check a builder before you let them start

The building trade has no single licence, so anybody can print a van livery. That puts the checking on you. These are the checks that actually tell you something, in the order worth doing them, and you should run every one of them on us as readily as on anyone else quoting.

• Look the limited company up on Companies House. Ours is number 14611254. Check the incorporation date, the registered address and that accounts are filed.
• Ask for the public liability insurance certificate and read the expiry date on it, not the broker's covering email.
• Read reviews on a platform where the reviewer had to have hired the trade. Ours are on MyBuilder: 4.9 from 31 verified reviews.
• Insist on a written, itemised quotation. A single figure on one line hides everything that later becomes an extra.
• Ask who signs off the structural work and who notifies building control. If the answer is vague, that is your answer.
• Ask for two recent addresses in London where similar work was done, and go and look at them.
• Check the payment schedule is staged against completed work. A large deposit before anything happens is the classic warning sign.

Our full guide to choosing a builder in London goes through each of these in more detail, including the questions worth asking on the first site visit and the answers that should worry you.

What building work costs in London

London prices are not national prices, and quotes that look cheap against a national average usually are. The ranges below are the ones we work to and publish across the site, so you can sanity check anyone else's number before you sign.

Type of work	What it covers	Typical London cost
Steel beam over one opening	Beam supply and installation, padstones, building control sign-off. The engineer's fee sits in the knock-through figure	£1,500 to £4,000
Full knock-through	Wall removal, beam, engineer's fee, propping and making good	£2,500 to £6,500+
Chimney breast removal	One floor. A steel beam is the usual route; gallows brackets only where the engineer and building control accept them	£2,200 to £3,250 on a steel beam; £1,500 to £2,500 where brackets are accepted
Kitchen renovation	Mid-range: quality units, stone worktops, integrated appliances, new layout	£20,000 to £40,000
Bathroom renovation	Mid-range: quality suite, porcelain tiling, new layout, heated rail	£7,500 to £12,000
Full house refurbishment	Mid-range per m²: strip out, rewire, replumb, heating, kitchen, bathrooms, decoration	£1,500 to £2,200 per m²
Single storey extension	Standard finish, per m² of new floor area	£2,000 to £2,800 per m²

Indicative London ranges, MyBuilder and Checkatrade, 2026.

Every project is quoted from a site visit, itemised, and free of obligation. The figures above tell you whether a quote is in the right postcode. Only a survey tells you what your house actually needs.

How a job runs, from first visit to final sign-off

A well run building job is mostly sequencing. The commonest cause of a project going wrong is not bad workmanship, it is trades arriving in the wrong order and undoing each other's work. This is the order we work in.

• Free site visit and survey, with an honest view of what the property needs rather than what is easiest to sell
• Written itemised quotation, with the provisional sums and exclusions stated plainly
• Structural engineer appointed where the work touches structure, and their calculations issued before anything is ordered
• Building control notified. Where the Party Wall Act applies you serve the notices as building owner, and we give you the drawings and programme they need
• Strip out, propping and structural work first, while the house is at its most disrupted
• First fix electrics, plumbing and heating, then plastering once the services are buried
• Kitchens, bathrooms, joinery and second fix, then decoration last
• Building control inspection and sign-off, snagging walked with you, certificates handed over

You deal with the same people from the survey to the snagging list. That is the practical difference between a builder and a project you are managing yourself.

Where we work

We cover all 32 London boroughs, 125 London neighbourhoods and 41 towns in the surrounding counties, with a page for every service in every area. If you already know the job you need, go straight to the service; if you know only the area, start with the borough below, or with the full list of areas we cover.

Four boroughs have their own builders page: builders in Enfield, builders in Barnet, builders in Islington and builders in Richmond, and the county our office is in has builders in Hertfordshire. If you want one firm to hold the whole job under a written contract, the building contractor page explains how that works, and the renovations page sets out what a renovation involves and the order it runs in.

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254). Prices are indicative and every quotation follows a site survey. Structural design is by the consulting engineer appointed to your project.