In 1905, the Johns-Manville company developed asbestos cement by mixing portland cement with asbestos fibres. The result was a brittle but fire resistant material used as a mastic and mortar for chimneys, skylights and for manufacturing house siding tiles until the 1970s. Due to the health hazards of asbestos, the U.S. Occupational Safety & Health Administration and Environmental Protection Agency now regulate its use. Breathing in asbestos fibres may cause cancer or other severe respiratory illness. Asbestos cement siding is hazardous only when it is broken, scraped, cut or drilled. The siding receives paint well but the tiles must be cleaned first. Latex paint is the preferred paint for asbestos cement siding, but needs a base coat of latex primer for proper adhesion. Select the highest quality satin latex paint and prepare the tiles properly for a perfect finish.
Select exterior latex paint containing 100 per cent acrylic. Latex paint resists the alkali in cements and masonry that disintegrate alkyd and oil paints. Air and moisture pass through latex paint, allowing dampness to escape and preventing the formation of paint blisters and cracks.
Select an exterior latex paint in satin finish. Satin finish is shinier than flat paint and flatter than semigloss. Satin paint will sufficiently repel rain and snow from the siding without giving the walls excessive shine.
Consider the architectural details and the age of the building when selecting siding colours. A Victorian home, or "painted lady," benefits from multiple, coordinating bright colours that enhance the cornices, gables, icicles, gingerbread and other architectural detailing. Earthy, woody tones of browns, greens and deep reds suit a Craftsman-style home with its geometric design and natural materials. Contemporary homes adapt well to a variety of colours and combinations.
Mix a diluted solution of one part chlorine bleach to two parts fresh water in the bucket. Wear safety goggle and rubber gloves to protect your eyes and skin from the caustic effects of bleach.
Dip the brush attachment on the end of the garden hose into the bucket. Turn on the hose and gently scrub the siding. The constant stream of water will prevent asbestos fibres from becoming airborne. Use the ladder to reach high areas, if necessary. Rinse well with the garden hose. Allow the siding to dry completely.
Apply masonry block filler to cracks or holes in the siding. Follow the manufacturer's instructions for drying time and applying a second coat, if necessary. Do not sand the filler.
Apply latex primer to the siding. Begin with the walls at the top of the building. To use the shingle paint pad, dip the pad into a paint tray of paint and shake out the excess. Place the pad at the top of the asbestos cement tile and stroke the pad down with the grain of the tile. After the walls are painted, paint the trim around doors and windows with the paintbrush. Paint architectural details last.
Apply latex paint to the siding, working in the same direction as you did the primer: walls, trim, architectural details. Allow the paint to fully dry according to manufacturer's instructions.
Apply a second coat of latex paint. Allow to dry thoroughly. Do not wash the siding for at least one week after the paint has dried.
Lay a large tarp over plants or a roof below the siding to prevent paint from splattering on them. Always mix the latex paint thoroughly before applying to the siding. Mix frequently as the job progresses to prevent the paint pigments and oils from separating.
Never sand, drill into, break or scrape asbestos cement siding. Use a soft-bristled brush attachment to loosen old paint and debris.
Tips and warnings
- Lay a large tarp over plants or a roof below the siding to prevent paint from splattering on them.
- Always mix the latex paint thoroughly before applying to the siding. Mix frequently as the job progresses to prevent the paint pigments and oils from separating.
- Never sand, drill into, break or scrape asbestos cement siding. Use a soft-bristled brush attachment to loosen old paint and debris.