Q: We have had a mold assessment that indicates non-toxic mold, but we are being advised to have professional remediation done at a cost estimated at $11,000. Since the mold is not of the toxic variety, is this really necessary? Some contractors also are telling us that we might have asbestos to deal with. Our house is 40 years old. We are more confused than ever.

A: Does the $11,000 cost include finding what’s causing the mold? It’s fine, I guess, to clean up mold, but if the source of the problem isn’t addressed, you’ll be spending money to clean it up every couple of years.

There’s no practical way to eliminate all mold and mold spores in the indoor environment; the way to control indoor mold growth is to control moisture. You’ll need to find the source of the moisture. Once you take care of it, odds are you won’t have a mold problem.

It’s not impossible that a 40-year-old house would have some asbestos, probably in textured paint used for popcorn ceilings or in floor tiles, or naturally occurring in vermiculite used as attic insulation. If it is not disturbed, deteriorating or damaged, asbestos is not much of a problem because fibers aren’t being released into the air.

If the mold-remediation contractor is going to disturb the asbestos, then you will have to have it removed by a licensed asbestos-abatement contractor before the remodeling project begins.