Asbestos in renovation: how to check before demolition

If the home you are renovating, or its surfaces, date from before asbestos was banned in your country (2005 at the latest across the EU, and earlier in many countries), you should find out whether asbestos is present before you demolish, sand or chisel. You can test a single suspect material such as tile adhesive, filler or the adhesive under a vinyl floor by taking a sample and sending it to a laboratory. Larger demolition or renovation work usually requires an asbestos survey carried out on site by a surveyor.

Finding asbestos during a renovation is nothing unusual. It was used in many common building materials and cannot be seen with the naked eye. In this article we explain how to find out whether asbestos is present, when a sample is enough and what to do if asbestos turns up in the middle of the work.

Why must asbestos be checked before a renovation?

Intact material containing asbestos does not release fibres. The risk arises when the material is damaged: sanded, drilled, chiselled or torn out. Fibres can then get into the air, and breathing them in can cause serious diseases such as asbestosis and mesothelioma in the long term.

The occupational safety rules also assume that, before demolition starts, it is established whether the materials contain asbestos. If you hire a contractor, they need to know which materials contain asbestos in order to plan the work safely. If you are unsure which rules apply to your project, check with your country's occupational safety authority – national rules differ.

The practical reason is just as important: if asbestos is only discovered during demolition, the work is stopped, the schedule slips and costs rise. Checking beforehand is almost always the cheaper option.

How do I know whether there is asbestos where I am renovating?

Only a laboratory analysis gives you certainty. But you can first assess the risk with three questions:

• When was the house built or last renovated? If surfaces or building parts date from before the asbestos ban, asbestos may be present.
• Which materials will you remove or damage? Typical examples are tile adhesive and grout, wall and ceiling filler, vinyl floor coverings and their adhesive, vinyl floor tiles, pipe insulation and various boards.
• Has the building been tested before? The housing association, the property manager or the previous owner may have an earlier survey or sample results. Check whether they cover exactly the materials affected by the renovation.

The most common renovations involve bathrooms, kitchens and floors. In the bathroom, asbestos can be in the tile adhesive and filler behind the tiles; in the kitchen, in the wall filler and in the adhesive behind the tiled splashback above the worktop; and in floors, in the adhesive under vinyl floor coverings and vinyl tiles. More on this in the articles Asbestos in the bathroom and Asbestos in tile adhesive.

Is an asbestos survey needed or is a sample enough?

That depends on how extensive the renovation is and what information is needed to plan the demolition.

• A sample is often enough if you want to know whether a single, clearly defined material contains asbestos. Examples are the tile adhesive in one room or an old vinyl floor covering. You can take the sample yourself following the instructions and send it to the laboratory.
• An asbestos survey is needed if many materials are to be removed, the renovation is extensive or a written survey report is needed to plan the demolition, which is often the case for projects run by housing associations. In a survey, a surveyor inspects the building, takes the necessary samples and writes a report.

Semlab is a laboratory: we analyse samples but do not carry out on-site surveys. If you need a survey, contact a surveyor near you. The difference is described in more detail in the article Asbestos survey or asbestos analysis. If you are not sure what suits your situation, you can ask us before you send samples.

How do I take an asbestos sample where I am renovating?

You can take the sample yourself if the material is intact and the sampling spot is small. The most important thing is to take the sample from exactly the material you will remove, and in such a way that all layers come with it. On a bathroom wall, for example, that means the tile, tile adhesive and filler right down to the base.

• Wear disposable gloves and preferably a respirator of at least class FFP3.
• Lightly moisten the sampling spot to keep dust to a minimum.
• Use a knife or chisel to remove a piece of about 2–5 centimetres and put it straight into a resealable plastic bag.
• Place the bag in a second bag and write the room, location and material on it.
• Cover the sampling spot with tape and wipe the surface with a damp cloth.

Take a sample of every material that differs from the others. If the floor and walls in the bathroom have different tiles and adhesives, those are two different samples. You will find more detailed instructions in the article How to take an asbestos sample.

What do I do if asbestos turns up in the middle of the renovation?

Stop work at that spot immediately. Do not carry on sanding, drilling or tearing out, and do not clean up the dust with an ordinary vacuum cleaner or broom.

1. Close off the work area and keep other people out of the room.
2. Take photos and note down the exact location and material.
3. Take a sample of the suspect material under controlled conditions, or call in a professional if the material is damaged over a large area.
4. Wait for the laboratory result before deciding how to proceed.
5. If the result is positive, the demolition is planned as asbestos work and carried out by a specialist asbestos removal contractor.

If the result is negative, you can continue working on that particular material. Remember, though, that the result only applies to the material tested: if a new layer or a different material appears during demolition, that is tested separately too.

A calm stop is almost always cheaper than guessing. You will find a more detailed procedure in the post Suspected asbestos in the middle of a renovation.

Checklist before starting the renovation

Go through these points before the first tile is removed or the filler is sanded:

• Find out how old the building and the surfaces are.
• Make a list of the materials that will be removed, sanded or drilled during the renovation.
• Ask the housing association, the property manager or the previous owner about earlier surveys and sample results.
• Decide whether a single sample is enough or a survey is needed.
• Take the samples following the sampling instructions so that all layers come with them.
• Label each sample: room, location and material.
• Build the time for the results into the schedule before demolition begins.
• Tell the contractor and everyone else involved about the results before work starts.
• If asbestos is found, get a quote from a specialist asbestos removal contractor before you award the contract for the work.

How much does analysing an asbestos sample cost?

At Semlab the analysis costs €49.99 incl. VAT per sample. The price is the same for 1–100 samples. Postage is not included. The samples are sent as a letter or small parcel with your national postal service to the laboratory in Finland and analysed with a JEOL SEM-EDS electron microscope, and you receive the result by email, usually on the same day the sample arrives at the laboratory. If you send the samples well before demolition and allow a few working days for delivery, you will have the result before the work begins. See the prices or order the analysis online and pay by card.