Published 2026-10-04 · Updated 2026-10-04 · Alpha Services Benelux

In what order should you renovate a house in Belgium?

Short answer: Renovate from the outside in and from rough to fine: survey and investigation, design and permit, ordering, building envelope, technical installations, finishing. Belgian sources put on-site work for a full renovation at roughly 4 to 12 months, on top of design, permit and delivery lead times. The envelope comes before heating so the heating unit is not oversized.

Prices in this article are indicative Belgian market ranges, not Alpha Services Benelux's price list. Your fixed price is in the quote.

The right order in six phases

The proven order is: find out what you have, design, order, deal with the envelope, install the technical systems, then finish. Reversing phases often means opening up walls and floors again.

1. Survey and investigation: condition of roof, facade, damp, electrics, pipework, EPC and possibly asbestos.
2. Design, budget and permit: drawings, quotes and, where needed, a permit.
3. Ordering and lead times: windows, joinery and appliances reserved in time.
4. Demolition, structure and envelope: roof, windows and facade so the house is wind- and watertight.
5. Technical installations: electrics, plumbing, ventilation and heating in the open walls and floors.
6. Finishing: plastering, screed, tiling, kitchen and bathroom, interior doors, painting and flooring.

Renovatie Kampioen sums it up as outside in, rough to fine. For one coordinated team, see our renovation page.

Survey, investigation and design: the phase that shapes the site

Expect several months of preparation before the first day on site; design, permit and quotes partly overlap. Sources differ widely, depending on project size.

Have a professional carry out the survey. Damp, a failing roof or ageing pipework set the order: repairs first, then insulation, then technical installations. The technical survey can run alongside the design, so no time is lost.

Ordering and lead times: start early

Windows and made-to-measure items are the classic delays. According to InterieurKabinet, window delivery can take up to 10 weeks and custom interior joinery about 10 weeks.

So reserve windows, exterior doors and custom items as soon as the design is fixed, even if the site does not start yet. A quality contractor may itself be booked 6 months or more ahead. Plan early and agree the start date in writing.

InterieurKabinet suggests considering standard or in-stock products when a lead time is too long. Order the kitchen and bathroom definitively only after the technical measurements.

Why the envelope comes before heating

An insulated house needs less heating capacity, so you choose a smaller, cheaper and more efficient unit. Doing it the other way round often ends in an oversized boiler or heat pump.

• Facq gives the rule: insulate first, then heating, solar panels last.
• Bouw Vlaanderen calls an oversized heat pump in a poorly insulated house an expensive mistake that is hard to correct later.
• After insulation a lower flow temperature is enough, which suits a heat pump better.
• Vaillant notes that a hybrid heat pump can be an intermediate step when you cannot insulate everything at once.

Within the envelope you usually start with the roof: according to Bouw Vlaanderen, up to 30% of heat loss goes through it. Have a professional assess your house, as every building differs. See our boiler and heating page for advice before choosing a heating unit.

Technical installations and finishing on site

On site the phases follow a fixed sequence: demolition and structure, envelope, technical installations, finishing. For a full renovation the sources place on-site work between 4 and 12 months.

All cables and pipes go into the wall before plastering. Have electrics and plumbing inspected before closing walls; reopening after plastering is, according to Renovatie Kampioen, the most expensive mistake. Painting comes last, after the kitchen and interior doors. For bathrooms specifically, see our bathroom renovation page.

What drives the timeline

Scope, permit, lead times and coordination weigh most. That is why sources differ and why we give ranges.

• Scope: a bathroom or kitchen finishes sooner than a whole house.
• Permit: a forgotten procedure can delay the site by months.
• Deliveries: windows and custom items up to about 10 weeks.
• Drying: screed 6 to 8 weeks, always to be respected.
• Hidden defects: damp, rotten timber or asbestos shift the schedule.
• Coordination: with one partner preparation takes about 4 weeks according to InterieurKabinet; with several parties, two to three times longer.

Bouw Vlaanderen advises a 10 to 15% buffer for unforeseen costs. Allow a comparable margin in time.

Comparing quotes and avoiding surprises

Compare quotes on sequence, schedule and scope, not just the final price. Ask every contractor the same questions.

• Which phases and works are included, and who coordinates the other trades?
• A written start date, a planned end date and what happens in case of delay.
• Who orders windows and custom items, and when?
• When are electrics and plumbing inspected, before plastering?
• What is excluded (demolition, waste removal, repairs once defects are found)?

Alpha Services Benelux is a contractor working with its own team, active since 2014. After a site visit you receive a fixed written quote; renovation is always by appointment. For a first indication, use the renovation calculator.

VAT at 6% or 21%, and premiums

According to Test Aankoop, the reduced 6% VAT rate applies to works on a home at least 10 years old, mainly used privately, where a tradesperson both supplies and installs the materials. Materials you buy yourself stay at 21%.

Exception: for supply and installation of a gas or oil boiler, 21% always applies since 29 July 2025; for a (non-hybrid) heat pump, 6% applies, even in a home under 10 years old.

Premiums differ by region and change regularly. In Flanders, Mijn VerbouwPremie depends on your target group: check vlaanderen.be/mijn-verbouwpremie. In Brussels, Homegrade gives free advice on prioritising works, and municipal premiums may exist. In Wallonia, see energie.wallonie.be. A premium should never be the reason to change the order of works.

Frequently asked questions

How long does a full renovation take in Belgium?

On-site work averages 4 to 9 or 6 to 12 months according to Belgian sources. Add design (1 to 3 months or more) and permit (30 to 105 days in Flanders). The whole journey easily exceeds a year.

What comes first: roof, windows or heating?

Start with the envelope: roof, then facade and windows, then ventilation, and only then heating. An oversized unit in an uninsulated house is an expensive mistake. Have a professional assess your house.

How long must screed dry before the floor goes on?

According to Bouw Vlaanderen, 6 to 8 weeks, and that drying time must always be respected. Plan it before tiling or parquet, or finishing will be delayed.

When should I order windows and custom joinery?

As soon as the design is fixed. Windows can take up to 10 weeks and custom interior joinery about 10 weeks. Order before the site starts, not when the facade is already open.

When should I request quotes?

Allow 4 to 6 weeks to collect quotes. A quality contractor may be booked 6 months or more ahead. Start well before your desired start date.

Sources

1. Stappenplan totaalrenovatie: van afbraak tot afwerking — Renovatie Kampioen
2. Huis renoveren in Vlaanderen: stappenplan 2026 — Bouw Vlaanderen
3. Hoe lang duurt een renovatie? — InterieurKabinet
4. Rénover sa maison en Wallonie : guide complet 2026 — STM Construct
5. Hoe maak je je huis milieuvriendelijker en energiezuiniger? Gids 2026 — Facq
6. Een duurzame renovatie met een warmtepomp — Vaillant Belgium
7. Wanneer en hoe krijg je verminderd btw-tarief van 6% voor werken aan je woning? — Test Aankoop
8. Mijn VerbouwPremie (in English) — Vlaanderen.be
9. Homegrade : accompagnement gratuit pour améliorer son logement — Bruxelles Environnement
10. Énergie - Wallonie — Service public de Wallonie