Dear Glenn: Three days ago, my toilet overflowed and continued to run while I was away for the day and lightly flooded two bedrooms and bathrooms. The bottom 6 inches of the walls show moisture content. I don't have the money at the moment to have my home remediated. I was hoping you could recommend a procedure to follow regarding cutting the sheetrock and setting up dryers and then what to use to disinfect the affected areas.

Bill, Houston

Dear Bill: Immediately opening up the walls after flooding is imperative. Just saw the sheet rock and pull out any insulation. Wear a dual canister respirator that you can get at many hardware stores. The official government designation is an N-95 respirator.

Unfortunately, the 72-hour time line is critical. The water behind the walls is as contaminated as sewer water. Go to my help site, www.masterhandyman.com. Click on "Mold Menace" in the left hand column. Click on "A Brief Guide to Mold, Moisture and Your Home" and "Mold Remediation in Schools and Commercial Buildings." Read both articles. "A brief guide" is an easier read. "Mold Remediation" gives more specific directions.

Dear Glenn: I have gable vents and pot vents and no eaves. Does this exchange my attic air? I just read in your newsletter where you suggested that a gentleman having only gable vents give the hot roof theory a try. Do you suggest that for me also even though I have pot vents?

Cathy, Warren

Dear Cathy: Gable vents just disrupt the airflow. You need soffit vents. They make special vents for people with no eves. You need to find a roofer with the expertise to install them. Some are Kearns Bros. Inc., (888) 355-6700; Chris J. Gentile Roofing and Sheet Metal, (248) 583-0465; or A & Z Roofing, (248) 395-7300, to install them.

You might consider the hot roof theory, which would eliminate all attic venting as well as sealing the attic roof and gables with foam insulation. To find out more about the theory, go to my help site and type "Hot Roof" in the search engine. You want to read my July 14, 2001 article "Homeowners have new insulation option in the Hot Roof Theory."

Dear Glenn: A few months ago, I was listening to you on the radio. I could have sworn you said you could increase energy efficiency by about 90 percent. I also thought you said you had a book that details all the steps to accomplish this. Am I remembering correctly? Is there such a book? If so, I'd be interested.

Cammie, Metamora, Ill.

Dear Cammie: You probably mean my "100 Most Important Home Improvement Questions."

Unfortunately, that book is sold out and has not been reprinted.

By the way, the 90 percent is faulty memory. I talk about a 90 percent efficient furnace and geothermal heating systems which can reduce your heating and cooling bills by about 70 percent, but I can't tell you how to cut your heating bill by 90 percent.

If you wanted to save 100 percent on your transportation energy bill, I could tell you to use a bicycle, but I doubt that you would do that. There is usually a trade-off between energy efficiency and cost efficiency. For instance, you could install energy collecting shingles on your house. According to PATH, A Public-Private Partnership for Advancing Housing Technology, a flat-plate solar collector system that would be efficient enough to supply very limited hot water needs costs between $2,500 and $3,000 and produces 80 to 100 gallons of hot water per day. If you wanted to install enough solar collectors to supply half your family's electric energy needs it would cost $40,000 or $50,000, and the entire system would set you back about $90,000 or more. And you would still be only 50 percent efficient.

The real choice is between what we presently perceive as quality of life and energy efficiency. If we want to be energy efficient we have to reduce the size of our homes and reduce energy consumption. Unfortunately, all the studies show the usage trend is up, not down.

Could you recommend one over the other and a local distributor versus buying the materials over the Internet?

Dan, Ortonville

Dear Dan: Check out Better Life Technologies before you buy anything, www.bltllc.com. The BLT G-Floor Mat is a vinyl mat that you can get to fit your garage floor. It's impervious to oil, salt, whatever. When it gets dirty, just drag it out of the garage and wash it off with a garden hose. It's that easy. The best price I've found for this was at samsclub.com. I have also seen it in their stores.