Asbestos in facade panels is one of the most well-known asbestos risks in Finland. Facade boards made of asbestos cement, especially Minerit, Eternit and Luja, still cover the exterior walls of thousands of 1950–1985 built properties. The boards were used both in single-family houses and townhouses, as well as in apartment buildings, schools and industrial buildings. When the facade reaches the age of renewal, the asbestos content of the sheets must be determined before the work begins.
What are asbestos cement sheets
Asbestos cement board is made by mixing asbestos fibers with Portland cement, which act as a reinforcing fiber material. The end result was a light, durable and non-flammable board that could withstand the weather conditions of Finland excellently. The boards were produced in many different profiles and sizes, and they were popular precisely because of the low price, lightness and long service life. Asbestos was typically 10–15 percent by weight in the boards.
Typical board types and manufacturers
in Finland asbestos in facade panels practically means the following products:
- Minerit, a Finnish flat or profiled facade panel
- Eternit, an international brand, corrugated sheets and flat sheets
- Strong, domestic asbestos cement board, common with 1960–1970 numbers
- Corrugated sheets, which were also used as roofing and wall cladding
- Profiled facade panels in industrial buildings
- Smooth flat plates on balconies and facades of apartment buildings
The majority of these products were manufactured containing asbestos until the year 1985, after which they switched to asbestos-free fiber cement boards. Externally, however, the old and new plates resemble each other.
Weathering releases fibers
When the asbestos-cement board is intact in place, there is little shedding of the fibers. Over time, however, UV radiation, frost, humidity and mechanical stress weaken the cement mass. The surface corrodes, becomes mossy and begins to crumble. At this stage, fibers can come off the surface with the air flow and rain. Particularly harmful are boards that are cracked, broken or treated with a pressure washer, where asbestos fibers enter the environment directly.
Facade repair is always an asbestos risk
Renewal, additional insulation or cleaning of facade panels creates a risk whenever old panels are worked on. Sawing, drilling, sanding, pressure washing and demolition release microscopic fibers into the air. The fibers spread tens of meters away with the wind and travel through open windows into apartments. Because of this, the handling of asbestos cement sheets is only allowed for authorized asbestos removal companies that use appropriate protective equipment and isolation methods.
Survey and safe demolition
Facade renovation planning always starts with asbestos survey. The surveyor takes samples from different types of boards, and the laboratory confirms the asbestos content. Based on the report, clear instructions are given on how the plates must be dismantled, how the waste is handled and how neighbor protection is organized. After the survey, the contractor can prepare a realistic offer, and the property owner knows the costs in advance.
If you are planning to renew the facade in a property built 1950–1985, order an asbestos survey before contractor selection. In this way, the facade renovation proceeds safely and in accordance with the law.