Cottage Q&A
QUESTIONI've heard of a process called cornblasting for removing paint and stain from surfaces. Is it more environmentally friendly than the usual stripping methods?
ANSWER
The easy answer is yes. Cornblasting - that is, using ground corn cobs in a pressure sprayer as an abrasive material to remove old finishes - is one of the most environmentally friendly methods around, advises Bob Welch, technical director for the Master Painters Institute, a painting-standards organization for professionals based in Burnaby, B.C. Other organics, such as round walnut shells, are often used the same way. Softer and less abrasive than sand for blasting, these are less likely to damage wood surfaces. As a bonus, the particles that (inevitably) escape containment are biodegradable. And, adds Welch, anytime you can avoid using the powerful caustics that are essential ingredients in even the newer "biodegradable" strippers, you're doing the environment a favour.
Some caveats, though. Unless you're a dab hand with a pressure sprayer yourself, you need to call in a professional. Even with organic abrasives, the high nozzle velocities a sprayer puts out can scar and splinter a wood surface, especially if it's a soft wood like pine. Professionals should know how to damp down the velocity and keep the nozzle moving evenly. And you should check out their credentials before letting them loose on your cottage, says Bill Withey, of Prepared Surfaces Sandblasting & Staining in Minden, Ont. If you can, inspect a job the contractor has already done. Look for unintended damage, such as scarring or pitting of the wood surface.
If there's lead in the old paint layers you want to get off - and chances are there is if the cottage is more than 50 years old - stop right there, and call for a certified specialist in lead paint removal. Abrasive blasting of any kind will create airborne lead particles, a serious health hazard.
* Published in the November/December 2003 issue of Cottage Life
