Having a wall knocked through or removed: what does it cost and what do you need to arrange?

Is the wall load-bearing, and what does that mean for the cost?

A load-bearing wall, or a load-bearing chimney breast, holds up part of the house, such as a floor or the roof. If you take a section out, something else has to carry that load. A non-load-bearing partition only separates spaces. That difference decides which steps are needed, and with them most of the cost.

Check the current rules for your region and municipality; in Flanders, via the Omgevingsloket (the online permit portal). Stricter rules apply to a listed building.

You cannot always tell from the wall itself whether it is load-bearing. A thick wall can be non-load-bearing, and a thin partition can still support a floor. Start by looking at the building plans for your house. If you are in doubt, have a structural engineer assess it before anything comes out of the wall.

The finishing is the same either way, including for a sliding door in a widened opening in the facade. After the opening is made, it has new edges and the wall around it is damaged. Those edges get corner beads and the wall gets a new coat of plaster, so that later you cannot see where the old wall stood.

When do you need a permit and a structural engineer?

With a load-bearing wall you always need a structural engineer, and usually a permit as well. Removing a load-bearing wall changes the structure of the house, and stricter rules apply than for ordinary interior work. Exactly what is required depends on your region and municipality, so check with the planning or urban development department of your municipality.

With the application, the municipality generally asks for details of the strength and stability of the new structure. These come from the structural engineer’s calculation, which also states which beam goes above the opening and what it rests on. Our contractor teams then carry out the opening as the calculation prescribes, including when the rear wall is opened up for an extension.

Removing a non-load-bearing interior partition is usually exempt from a permit. That applies as long as nothing changes in the load-bearing structure or the fire safety of the building. With a listed building, even interior work may need a permit.

Allow for the waiting time in your planning. A permit procedure takes time, and how long differs by region and by case. So start with the permit check for your renovation as soon as your plan is fixed.

What does the finishing cost after knocking through a wall? A worked example

The structural part differs from house to house: the thickness of the wall, the beam, the pipes inside it. That is why we put it in the quote after the consultation. The finishing you can work out in advance. Take an opening 2.4 metres wide and 2.3 metres high, with the wall around it on both sides.

On each side, an opening like this has three edges: left, right and the top. That is 2.3 + 2.3 + 2.4 = 7.0 metres, and on both sides 14.0 metres of corner bead on the external corners. The wall around the opening comes to 10 m² in this example.

Prices from our 2026/2027 price list, valid from 1 September 2026. Prices exclude VAT; for homes over 10 years old, 6% VAT usually applies. The measurements are an assumption, not an average.

If you have only the opening finished, the fixed charges are almost half of the amount. The small-job surcharge and the call-out charge come to €349.98 together, against €229.90 of plastering.

If the opening is part of a larger job, the surcharge falls away and you pay the call-out charge once. That is why we prefer to include an opening in the renovation of your house, with the walls and ceilings of the new space as well, or in the finishing of your extension.

After plastering, the coat has to dry. According to Knauf, gypsum plaster is dry enough to paint after about four weeks under good conditions. A plasterer plasters on average 100 m² per day, so in the example the plastering itself, at 125 m², is done within two days.

Can’t you just remove a non-load-bearing wall yourself?

You can. For a non-load-bearing interior partition you usually do not need a permit, and the demolition itself is not the hardest part. Still, the cost is rarely in the demolition. It is in what is left afterwards.

Interior partitions often contain pipes or sockets, which have to be rerouted first. After demolition you are left with a bare strip in the floor and ceiling and damaged edges in the adjoining walls. Those are exactly the spots you notice first after painting if they are not neatly finished.

Also watch the rules on demolition waste. Rubble has to be taken away or brought to a recycling centre, and it is wise to sort it. A wall 4 metres long, 2.6 metres high and 10 centimetres thick is about 1 m³.

Asbestos is the exception you cannot avoid. It may have been used in older homes, and damaged asbestos should only be removed by a specialist company. If you are unsure about an old layer on the wall, we discuss it in the consultation, just as with having old plaster removed.

How do you have a wall knocked through by us?

Request a quote or call us on weekdays between 9:00 and 17:00. In the free consultation we discuss which wall has to go, whether it is load-bearing and what else needs doing in the space. After that you receive a plan and a quote, with the finishing at the fixed prices from our price list.

If you agree, we measure up and check the walls. The final price and the schedule are then fixed, and we start on the day we agree together. The opening and the pipework come first, then the plastering, and after drying the paint or wallpaper.

The structural work is done by our four own contractor teams of four people each. The plastering is done by our 32 in-house plasterers, part of a team of 97 tradespeople on permanent contracts. That gives you one point of contact for the whole job, and we work throughout Belgium, in Flanders, Brussels and Wallonia.

You pay 50% on the first working day, once all materials are on site and we have started, and 50% on completion. If you want to tackle more than one wall, you can also have your whole home renovated by one contractor. Plastering alone is possible too: that is plastering walls during a renovation.