Canada Mortgage and Housing Corporation (CMHC) describes many ways in which asbestos can become a risk - disturbing loose-fill insulation, removing roof shingles or siding, tampering with roofing felt, ripping away asbestos insulation from a hot water tank, sanding or scraping asbestos floor tiles, breaking apart acoustical ceiling tiles, and sanding plaster or coatings such as roofing compounds, sealants, paint, putty caulking or drywall containing asbestos.
Disturbing asbestos-containing materials can release microscopic fibres into the air.
While there are regulations governing asbestos removal, private homes or residential buildings with four units or less are exempt. If homeowners suspect asbestos is present and may be disturbed during renovations, they are advised to consult an expert in asbestos abatement and removal.
Buildings constructed or renovated in Canada between 1950 and 1978 may also have Polychlorinated biphenyls (PCBs)-contaminated caulk around windows and door frames, between masonry columns and in other masonry building materials. PCBs were added to caulk to increase its flexibility. PCBs cause cancer in animals,and their use in caulking was discontinued in 1978. Dust created during renovations can be contaminated with PCBs from this older caulking.
Choosing healthy building materials
The report notes that sealing and tightening a building to improve energy efficiency can reduce air exchange, resulting in more concentrated levels of indoor pollutants and potential health troubles.
And new building materials such as such as caulking, sealants, glues and insulation that contain volatile organic compounds can off-gas or release toxic chemicals such as benzene, toluene and formaldehyde.
Recent studies have shown that the risk of asth
|Contact: Terry Collins|
Canadian Environmental Law Association