Jun 28, 2014 5 min read

Q. A squirrel or several squirrels ate a hole in my lead flashing, and now it leaks badly when it rains. Water from the roof runs down into the hole. The top of the flashing is cemented into the chimney between the bricks. The job appears to be well done and has lasted many years. The hole is about the size of a squirrel’s head. How can I repair it?

A. The squirrel is doing what it has to do to shorten and sharpen its teeth: gnawing. The lead is just right for him: soft but able to keep wearing down the teeth. Buy a heavy-duty piece of sheet aluminum or galvanized steel big enough to cover the hole and surrounding area. Lead flashing around chimneys is usually not glued to the roof, so lift it carefully, slather the roof and patch with roofing cement, and insert the patch under the flashing. If the flashing is glued to the roof, you can put the patch directly on top.

Putting the patch under the flashing might work better, so keep an eye on the on-top patch and see how long it lasts. Finally, treat the patch with a critter repellent, sold in hardware stores.

Q. I renovated a split-level ranch last year. I am getting septic odors downstairs in my house quite frequently, especially after a family member has showered. Odors seem to be coming from the laundry room where the vent stack is in the house. I’m not sure what’s causing the problem. Any ideas on what I can do to fix it?

A. It sounds as if the vent stack is blocked or unconnected to the shower room and other places. The vent stack takes septic fumes up through the roof, where they are released. An unvented shower, toilet, or any other appliance can be dangerous. Have a plumber check it out and clear the stack. Don’t wait; septic gases can be lethal.

Q. My wooden front door has developed a long crack wide enough to see light through it. Can it be sealed with plastic wood or wood filler, or should some other method be taken to save the door?

A. The crack must be in one of the panels, which are thinner than the frame pieces. This was caused by expansion and contraction of the wood. Try this: Buy adhesive caulk that will firm up as hard as plastic wood or wood filler. Fill the crack with this caulk, pressing it in with your fingers. Hold a board on the other side to keep the caulk from oozing through. Let it set. You can scrape it smooth. Do the other side if necessary, and finally paint the panel to match the door.

Q. We have a forced hot air heating and air-conditioning system. I see ads all the time for air-duct cleaning. My heating, ventilation, and air-conditioning company doesn’t do it, and they have said that such cleaning can damage the ducts. Do you have an opinion?

A. If your ductwork is more than 25 years old, it’s a good idea to have it cleaned. Sure, damage can ­occur, but it’s rare and reputable companies will fix it. My own ducts are 50 years old, and were they ever stuffed with dirt, crud, and you name it. I had them cleaned, and they’ll be good for another 25 years or so. Do it!

Q. Interestingly I was reading your column in Sunday’s Globe about carpenter bees vs. bumblebees. I have carpenter bees drilling holes in my shed, so I am familiar with their work and there seems to be only one or two hovering around my head. While cleaning gutters recently, I saw what appeared to be many bumblebees going in and out of space on the fascia, possibly into the attic area. They came out like a swarm, landing on my face. I believe these were some type of bumblebee, but I could be wrong. I sprayed insecticide, but what now? How do I make sure they are dead? Should I caulk the hole or fill it with expanding insulating foam?

A. Don’t use insecticides. Bees are beneficial, because they are pollinators. Fill the holes with adhesive caulk and/or replace the damaged wood.

Q. Two sparrows are trying to build a nest inside my dryer vent. I’m on the second floor of a three-story turn-of-the-century brick apartment block. Outside access to that window is limited. How can I keep them out?

A. One answer is to let them nest, then in spring they will produce little ones and all will fly the nest. Or, fasten an insect screen just inside the flapper door. Or, have a new fan installed with a heavier flapper door that will stay closed when the fan is off.

Q. I have several smoke detectors from about 10 years ago that have turned brown. I see that they say “do not paint” on the covers. What causes this discoloration and is total replacement the only answer or what can I do to make them white again so they do not stand out on the bright white ceilings?

A. I don’t know how or why they turned brown. Did they go off when they detected smoke, which could have discolored them? At any rate, generally it is suggested to replace them every five years, so you can do that to keep safe.