For the owner of an old house, asbestos is a familiar worry, especially once a renovation comes up. Asbestos was used widely in Finnish construction from the 1920s to the early 1990s, so almost any house built before 1994 may contain asbestos-containing materials. This article goes through what the owner of an old house should know and check.
Typical asbestos locations by decade
The use of asbestos varied from decade to decade. In houses from the 1950s and earlier, asbestos turns up above all in pipe insulation, asbestos-cement (eternit) sheets and around fireplaces. In 1960s houses the common asbestos materials are tile adhesives, floor adhesives, vinyl flooring and wall fillers.
In 1970s buildings, asbestos is often found in the same places as in 1960s houses, and additionally in acoustic panels and ventilation duct insulation. In 1980s houses the use of asbestos began to fall away, but it still appears in tile adhesives, fillers and pipe insulation. The last asbestos-containing materials were installed in Finland in the early 1990s, before the ban took effect.
What to check before a renovation
Before the work starts, the owner of an old house should work out which materials the removal work will touch. Check these in particular: bathroom tile adhesives and grouts, wall fillers, vinyl flooring and its adhesive, pipe insulation, roofing materials and boarding. Any of them may contain asbestos.
A good way to begin is to look up the year the house was built and find out whether it was renovated before 1994. If it has been renovated several times, materials from different periods may be layered on top of one another.
A practical approach
Investigating asbestos in an old house does not mean testing every material at once. The most practical approach is to test the materials the renovation actually affects. If you are planning a bathroom renovation, sample the bathroom materials. If the floor is being replaced, test the floor material and its adhesive.
This targeted approach is both cost-effective and sufficient in most situations. A full building-wide survey is only warranted when the whole house is being refurbished or demolished.
Intact material vs. material being taken out
It is important to understand that intact asbestos-containing material inside a structure poses no immediate danger. Asbestos becomes harmful only when the material is broken and fibres are released into the air you breathe. That is precisely why the asbestos survey matters most immediately before removal work.
If you are not renovating an old house but are thinking of buying one, you can ask the seller for any asbestos surveys that have been done. Many condition assessments carried out for a house sale do not include an asbestos survey, so it is worth asking about separately.
Detached houses and terraced houses
Asbestos can be very widespread in detached houses, because they have often been renovated several times over the decades. Asbestos-containing materials may have been used in each of those renovations, so the structure can hold several layers of asbestos on top of one another.
The situation in terraced houses is often similar, with the added point that the structures the housing company is responsible for - facades, shared pipework and roof structures - have to be taken into account too. The housing company board should settle the asbestos question before any shared renovation project.
How to proceed
If you own an old house and a renovation is coming up, start by establishing whether the materials to be taken out contain asbestos. Take a sample of the material, pack it and post it to the laboratory. The result tells you whether you can proceed with ordinary removal work or need the help of an asbestos removal company.
An old house is not a problem - it is an opportunity. Once you know what the structure is made of, you can plan the renovation safely and efficiently. An asbestos survey is a small investment that buys certainty and peace of mind.