🇧🇪 Brussels · Wallonia · Flanders 🔨 Guide

Renovation: choosing a contractor, and protecting yourself

A building job that goes wrong rarely costs you because of a bad price. It costs you because of a vague quote, too large a deposit, an invoice that loses you the grant, or a handover signed too quickly. Here is how to choose, contract and accept the works, in order.

A work table in a brick house under renovation, with a printed quote and a tape measure, a ladder and a freshly plastered wall in the background.
The quote on the table decides almost everything that follows: price, deadlines, grant, recourse.

Check the firm first

Five minutes are enough, and they prevent most nasty surprises. Using the company number on the quote, look it up in the Crossroads Bank for Enterprises (CBE), online and free:

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The firm exists and is active Name, registered address, date of incorporation, status. A company set up a few months ago, or whose address does not match the quote, deserves questions.
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It is registered for VAT Without an active VAT number there is no proper invoice — so no reduced rate, and often no grant.
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Its activities match the works The CBE lists the registered activities. In Wallonia and Brussels, several construction trades are still subject to professional access requirements; Flanders abolished them. A roofer registered for retail trade is a warning sign.

Then ask for recent references for comparable jobs, and call at least one. Ask for a certificate of professional liability insurance, and of ten-year liability insurance if your works are subject to it — see below.

Reading a quote — and comparing

A good quote is written, dated, and detailed enough for another contractor to price exactly the same thing. If it fits on three lines, it protects you from nothing.

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Items, quantities, materials Areas in m², brands and references of materials, insulation thicknesses, performance. Without them, two quotes cannot be compared: one may be cheaper because it prices less.
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What is included, and what is not Demolition, waste removal, scaffolding, finishing, cleaning. Almost all the "extras" on a job come from what the quote did not say.
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Deadlines and validity Start date, duration of the works, and how long the price is guaranteed. A price valid for one month for a job in six months' time is not a price.
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The VAT rate and payment terms The rate applied must be stated, with payment instalments tied to the actual progress of the works.
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Ask for at least three quotes, all based on the same specification that you write yourself — even a simple one. It is the only way to compare prices rather than different interpretations of your request.

VAT and grants: the invoice matters

Renovation work on a private home that has been in use for a long time can qualify for a reduced VAT rate, provided the contractor invoices the end consumer directly and the home is older than a minimum age. The contractor applies the rate, but you sign the statement that justifies it: if the conditions are not met, the difference can be claimed from you.

For energy grants, the invoice is often the deciding document. Several regional grants require the works to be carried out by a registered contractor, an energy audit to have come first, or the material's performance to appear on the invoice.

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Before signing, read the conditions of the grant you are aiming for and ask for the invoice to state exactly what it requires: performance, areas, material reference, site address. A grant is lost far more often over a badly worded invoice than over a technical criterion.

For specific works, our pages on roof insulation, wall insulation and heat pumps set out each Region's requirements.

The contract, the deposit, the deadlines

A quote signed by both parties is a contract. Before signing, check that it contains what protects you:

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A reasonable deposit A deposit on ordering is justified for made-to-measure materials. Paying most of the price before work starts, never: it is your only leverage if the job goes off the rails. Then pay in instalments tied to progress, by bank transfer only.
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Deadlines and a late-completion penalty An end date and, for a large job, compensation per day of delay. Without a date, a delay can hardly be held against anyone.
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A procedure for changes Any extra must be accepted in writing, with its price, before it is carried out. That is the clause that prevents the surprise final bill.

For building or heavily converting a home, the Breyne Act imposes a strict framework: written contract, price, deadlines, a cap on the deposit and a completion guarantee. It does not apply to small works, but if you are having a house built or buying off-plan, check that your contract complies.

During the works

Keep a site diary: dated photos of every stage, especially of what will be hidden later — insulation, waterproofing, wiring, pipes. It is the only proof of what was fitted once the ceiling is closed, and several grants ask for exactly those photos.

Communicate in writing — an email is enough — about anything that changes: an unavailable material, an extra, a delay. A verbal agreement on a building site is a disagreement waiting for its moment.

Handover — the trap

Handover (acceptance) is the act by which you accept the works. It often happens in two stages: a provisional acceptance at the end of the job, then a final acceptance after an observation period set in the contract.

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Signing the acceptance without reservations in principle means accepting every defect visible at that moment. You can no longer complain about them afterwards. So never sign in a hurry, on the day the workers pack up their tools: walk round, write down every defect you find, and have them recorded as reservations.

If you are not qualified to judge — a roof, a heating installation —, get someone to help. An architect, an independent expert or even a friend in the trade will see in an hour what you would not see in a year. Hold back part of the final payment until the reservations are cleared, if the contract allows it.

Afterwards: the guarantees

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Ten-year liability The contractor and the architect remain liable for ten years for serious defects that threaten the building's soundness or stability. It is a statutory liability that no contract can exclude.
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Compulsory ten-year insurance For works on a home that require an architect, contractors and architects must be insured for this liability. Ask for the certificate before work starts: if the firm goes bankrupt, the insurer answers for it.
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Hidden defects A defect that was invisible at handover and less serious than a ten-year defect can still be invoked, provided you act quickly after discovering it. Report it in writing as soon as you notice it.
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Manufacturers' warranties Boilers, heat pumps, windows, inverters: the manufacturer's warranty often requires registration and annual servicing. Keep invoices, technical sheets and servicing certificates together — you will need them when you sell, and for the EPC certificate.

What we do not put figures on

The applicable VAT rates and their exact conditions (age of the home, type of works, special regimes), the Breyne Act deposit cap and prices per m² for works are not extracted from our sources, and we do not publish them. Grant amounts are, Region by Region, on our dedicated pages.

In a dispute with a contractor, a written attempt at an amicable settlement always comes before going to court. The FPS Economy points consumers to the competent ombudsman services.

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Never sign a handover without having reread it on site, with the works in front of you. That signature decides what you can still claim.

Further reading