Q. We live in a mobile home. During the summer, we sometimes smell a strange odor in the bathrooms and under the sink. We checked underneath to make sure there were no dead animals, cleaned the cupboards, and deodorized all the drains, but nothing works. We have a regular discharge pipe and it is not a sewage problem.

A. Though you say you have already checked for dead animals, there may be one spot you have missed: under the floor beneath the shower. Smaller animals like rodents can crawl into spaces as small as an inch and become trapped. Check this and any other smaller openings where there is even a remote possibility of a trapped animal, and hopefully you can track down and remove the source of this odor. Once you have located an opening, seal it with a patching compound, expandable foam sealant or caulk.

The way to remove a dead rodent, if you find one, is by cutting in a small access hole from below the shower or tub. A mirror and flashlight can be used to inspect the area and remove any surprises. The access panel can be screwed back into place and caulked shut. This can be done by a small repair contractor or handy-person.