Renovation includes sanding and varnishing the original wood parquet floors. Unfortunately, very little effort is being made by the floor contractors to ventilate the varnish fumes. The fumes build up in hallways and neighboring apartments. I've complained to management, to no avail.

Maybe I'm being an unnecessary alarmist. Are such fumes very toxic in an enclosed space? What about the fumes interacting with a gas stove? It's a cat- and dog-friendly building - as well as some new babies.

Answer: I think your concern is justified. The Environmental Protection Agency has a long list of common products that emit these harmful fumes such as minerals, varnishes, enamels, lacquers, stains, latex, and water colors. People react to these indoor pollutants in different ways; the most chemically sensitive have the severest reaction, and such exposure could increase in severity as the years pass.

Children? I would assume that babies and people with respiratory illnesses would react the most to the fumes. I also believe, however, that everyone, even the healthiest among us, would have a problem with the fumes after time if they continued to build.

As far as a problem with the fumes and gas stove, I would say that, under the right conditions, the combination could cause a problem.

It would be simple to ventilate the area being varnished, using large fans at windows to exhaust the odors out of the building. The workers also could use a less-toxic, water-based varnish that would not produce the same fumes.

Remember, too, that varnish fumes linger awhile after the workers have left. It's probably better for everyone involved, including the workers, to use products that are less harmful to themselves and the environment.

Q: I have a 16-foot-by-32-foot inground pool and am thinking of filling it in. It is more than 30 years old and needs a new liner and maybe wall work done. The pool company said it could cost up to $18,000 to get it into shape. What would be the best way of filling it in?

A: I would suggest calling the municipality first to see if it has any rules governing taking pools out of service. Local officials may require a permit, at least, or may want to inspect the job at some point to make sure that what's used can't bury your next-door neighbor's yard in a heavy rain.

Then call a contractor who specializes in this kind of thing. You might be able to use the concrete in the pool as filler after it is broken up - if the municipality allows - and the excavator punches holes in the concrete in the bottom of the pool so that rain and melting snow will drain properly.

You'll probably need to get a couple of estimates on alternative methods of filling. One can only hope that filling it will cost less than fixing it, but you never know.

Q: I live in a tri-level house with living space on all floors. Do you have any recommendations as to how to balance my heating system during the winter and my air-conditioning system during the summer? Nothing I have tried has prevented the lowest level from being cold in the winter and the top level from being warm in the summer. The thermostat is on the top level and is set at 68 in the winter and 78 in the summer. I know the laws of physics are against me, but I thought you might have some suggestions involving mechanical means to remedy this problem.

A: It's odd that the thermostat would be on the top floor rather than on the bottom. What the HVAC installer tries to do in locating the thermostat is to find a place lacking extremes - avoiding breezy hallways or spots below halogen lights.

I'd never put a thermostat on the top floor, especially in the summer, because the air conditioner would run constantly.

I would recommend moving the thermostat. An HVAC contractor - perhaps not the one who put it on the top floor in the first place - might help fix the problem or at least tell you why it can't be corrected.