Q. My front door is wood with a window and the back door is metal. They are the original ones and neither is efficient nor airtight. I cannot afford new ones. How can I improve their efficiency myself?
A. Energy losses from inefficient entry doors can account for a significant portion of your monthly utility bills. What makes things worse is leaky ones can create drafts in your house. When this happens, people tend to set their furnace thermostat higher and this wastes even more energy.
There are ways to improve the efficiency of old doors, but don't eliminate the possibility of installing a new one. Prices for some well-insulated steel and fiberglass doors, especially one for the back door without glass, are very reasonable. A prehung one is not difficult to install yourself.
Before you make a decision on what to do, inspect your old doors. If they are in very bad condition, it will be difficult to improve their efficiency by a meaningful amount. First, make sure the wood door is not rotting and it is not badly warped. Use a long straight edge to check this.
The most common problem with metal doors (most are steel) is rust, not warping. The first place to check is along the bottom by the weatherstripping on either side. Rainwater tends to collect there and it is not always painted well. Minor holes can be repaired with car body filler.
If the doors are reasonably sound, check for the location of the air leaks. At night, have someone shine a flashlight from outdoors around the seals and look for light reaching inside. On a windy day, move a stick of lighted incense around the seals and watch the trail of the smoke.
Often with wood doors, the majority of the problem is simply the latch plate is not holding the door tightly closed against the weatherstripping. Hold the door tightly closed and check for air leaks again. The steel door should have magnetic weatherstripping, so this is not a major issue.
One solution is to reposition the latch plate. This will require filling in the old screw holes and drilling new ones. Chisel away some of the wood in the recess for the latch plate. Another option is to install an adjustable latch plate because you may want to reposition it for summer and winter.
Check the condition of the hinges and replace them if needed. If the hinges and pins get worn, the door will not hang square in the opening, and therefore, will not seal well.
It is almost certain the seal on the bottom of the doors against the floor threshold is worn. If it is not torn, adjust the floor threshold higher. There are generic replacement seals you can install. An add-on retractable threshold seal works well and automatically lifts to the clear carpeting.
The following companies offer door improvement products: Duck Brand, (800) 321-0253, www.duckbrand.com; M-D Building Products, (800) 654-8454, www.mdteam.com; Pemko Manufacturing, (800) 283-9988, www.pemko.com; and Thermwell, (800) 526-5265, www.frostking.com.
Q. The duct from the exhaust vent fan in our bathroom vents directly through the attic. During winter, water sometimes drips off the grill in the ceiling. How can I fix this?
A. With a well-insulated house and properly ventilated attic, the air in the attic should stay cold. Your bathroom vent fan probably has a metal duct which also gets cold. Moisture in the exhaust bathroom air condenses and drips out the grill.
Try running the vent fan longer after your bath. This moves the moisture-laden air out of the duct quickly before it condenses. If there is a damper in the duct, make sure it swings closed when the fan is off.
• Write to James Dulley at 6906 Royalgreen Drive, Cincinnati, OH 45244 or visit dulley.com.