The Minerit sheet is Finland's best-known fibre cement board, used extensively on roofs, facades and the walls of wet rooms. Minerit sheets manufactured before 1988 contain asbestos in practically every case - after that, production moved to asbestos-free fibres, and the use of asbestos ceased altogether by 1994 at the latest.
What is asbestos cement board?
Asbestos cement board is a sheet pressed from cement and asbestos fibre. The asbestos gave the board strength, weather resistance and fire resistance. Product names and types include:
- Minerit - corrugated or smooth sheets on roofs and facades
- Vartti roofing - a shingle-like fibre cement roof covering, common in the 1970s and 1980s
- Smooth facade and balcony panels - balcony railings, plinths and eaves on apartment buildings
- Interior lining boards - panelling in wet rooms and around heating appliances
How do you identify an asbestos-containing board?
Reliable identification is impossible by eye - identical-looking boards were manufactured both with and without asbestos. Indications of asbestos:
- The building or the roof covering dates from before the 1990s
- The board is grey, hard and brittle - it breaks with a sharp edge
- Fine fibres may be visible in the fracture surface
- There is no marking on the back of the board indicating that it is asbestos-free (such as "NT", new technology)
The only certain way is laboratory analysis. A small piece of the board is enough for a sample - the analysis costs 39,90 € + VAT.
What about Luja board?
Luja board is a fibre cement board used especially in fire protection and interior linings. Older Luja boards (from before the end of the 1980s) may contain asbestos, newer ones do not. The same rule applies: the age gives you an indication, but only analysis gives you certainty.
Is an intact Minerit roof dangerous?
An intact, coated asbestos cement board does not release fibres into indoor air under normal conditions. The risk arises when the board is worked on: drilling, cutting, sanding and above all pressure washing release asbestos fibres. Therefore:
- Never pressure wash an old Minerit roof
- Do not drill or cut the board before you have an analysis result
- Removing the boards is asbestos removal work if asbestos is found - see the price of asbestos removal
Roof or facade renovation coming up?
- Take a small piece of the board as a sample and send it to our laboratory - a quick result, 39,90 € + VAT
- Or order an asbestos survey if the site has several suspect materials - from 119 € incl. VAT
- A negative result means the boards may be removed as ordinary demolition work and disposed of as construction waste