Caulking top and sides of storm windows helps create seal

Q. My 1,200-square-foot ranch built in the 1950s had wooden storm and screen windows when I moved in 10 years ago. I replaced them with stock aluminum storm/screen windows, which I purchased at Menards. The instructions advised to caulk the top and sides when installing. I did not do that and we just installed them with no caulk. I get lots of spider webs in the summer between the storms and double-hung interior windows. Since the interior windows are so old, but in good shape, I can't open all of them all the way to clean the inside of the storms. How would I clean the outside of the interior windows anyway unless I remove the storms?

My question is, is there really a problem with not properly caulking the storms? I can feel some cold air infiltrating in the winter at the bottom of the windows, but I don't see how caulking would prevent that.

A. The suggestion to caulk the top and sides of combination storm/screen windows is to seal them from wind and water penetration, and make them more efficient. The bottom needs to be uncaulked to allow any condensation in the winter and rain accumulation through the screens in the other seasons to drain out.

For spiders to get in the space between the storms and primary windows, they must be entering through the drain holes, unless there is a space between the bottom of the storms and the window sill.

To discourage the spiders, try spraying an insecticide on the windowsills and the inside bottom rail of the storms.

You will continue to feel cold air infiltration as long as the primary windows are themselves leaky. You can stop that by improving the weatherstripping of the primary windows. There are many types of weatherstripping available in hardware stores and home centers; choose the most appropriate one. Puttylike rope caulk, such as Mortite, is an easy one to install and remove in the spring for reuse next winter.

The storm and screen panels of combination storm/screen windows should be easily removable to allow you to clean them and the primary windows. It may also be worthwhile to free the primary window sashes.

Q. I have a particular problem that came up in a log house we own. We bought it at auction, so we did not get much, if anything, disclosed.

Anyway, a couple days ago, during this beautiful Indian summer weather when the temperatures rose well into the 70s, we were inundated with ladybugs. Literally thousands. I have been vacuuming them up, but they keep coming.

Any ideas on how to get rid of them? Thanks.

A. Are they truly ladybugs (which are very beneficial and should be preserved), or are they Asian lady beetles, a parasitic subspecies?

Here is a reprint of Entomological Notes from Penn State University's College of Agricultural Sciences Cooperative Extension:

"Multicolored Asian beetles are slightly larger than most native lady beetles, with adults measuring 9/32-inch long and 7/32-inch wide. They are oval or convex in shape, and yellow to red in color (with or without black spots on wing covers). The beetles' spots, which can vary in size and pattern, number from no spots to as many as 19. The head is usually concealed beneath the disk-shaped pronotum, which is cream to yellow in color with a black 'M' design in the center."

Common ladybugs tend to have fewer spots than Asian lady beetles. They are also much more passive. Asian lady beetles, on the other hand, are reportedly aggressive, and have been known to bite humans if they are picked up. When crushed, they emit a yellow, messy, smelly gel.

Asian lady beetles are usually found in large groups. Considering the numbers that beset you, these beetles are likely to be the Asian types, but to make sure, you can take a few to your local extension service or pest control operator for identification.

True ladybugs should not be destroyed and can be collected and given to gardeners or garden centers that appreciate and value them. They can also be stored in jars with a few holes in their tops, and refrigerated over the winter to be released in late winter and early spring, depending on the climate.

The nefarious varieties can be vacuumed up and disposed of.

Q. I just read your comments regarding venting bathroom and kitchen fans. I moved into a patio home where the dryer vent is on the roof. A roofer was on the roof recently and found the vent flap stuck open with hardened packed lint. He cleaned it out but this, to me, is a fire hazard and I'm wondering how or why it was vented out the roof and not the side of the house. Is this common to vent dryers out of the roof? I plan to pursue this with the building inspector, but I would welcome your expert advice first.

A. Dryer vents should not be vented through the roof, and I hope it is not that common. Venting them vertically results in what happened to your vent because of the resistance in the vent caused by the need to push air vertically. It represents a potential fire hazard.

They should be vented through a wall, and need to be checked regularly to make sure that the vent is not clogged up. It is also advisable to have a way of cleaning the duct by means of small special brushes made for the purpose, which you can buy in hardware stores.

Q. We had a cement slab poured at the end of our driveway two years ago when we replaced our carport with a deck. The slab is about 20 square feet and is 12 inches thick. The first year it held up well - but the second year it started to get long cracks in it. These are about 4 feet apart and run the entire length of the slab.

We asked the contractor and he put a sealant on the slab. However, the cracks are still open and I assume the sealant went into them but did not fill them up. Our concern is that these cracks will get bigger this year. Can you advise what should be done to fix it correctly?

A. Twelve inches thick! Wow! What was the reason for this thick a slab of concrete?

I wish you had sent me photos, but it sounds as if the cracks are shrinkage cracks, a normal occurrence on concrete slabs and walls as they cure, unless the concrete is reinforced with re-rods and steps are taken to allow it to cure properly.

My guess is that the contractor didn't score the concrete to create control joints, as he or she should have done in both directions every 10 feet on a slab this large. Shallow control joints sawed in the top of the concrete do just that: the shrinkage cracks occur at the control joints and are not objectionable; they are hardly noticeable.

The sealant has nothing to do with filling the cracks; it simply protects the slab from chemical damage from de-icing compounds and other sources, as well as from deep water penetration, which can cause any ferrous metal in the concrete to rust over time.

In your case, unless there is some settlement going on, the cracks are unlikely to grow bigger.

There is not much you can do now if they are only hairline cracks, but if they are bigger than one-eighth inch, they can be filled with a vinyl-reinforced cement mix.

Q. We have a 1,900-square-foot ranch house with two-zone heat, the master bedroom and bath being one of the zones. We heat with propane, and during the winter we always keep the bedroom thermostat down to 65 degrees, and the other zone at 69 or 70 degrees. Is the colder air from the bedroom causing the other thermostat to come on more often? It is located across a large living room from the bedroom door. Should we keep both thermostats the same, close the bedroom door, or what should we do?

A. Interesting that you put the bathroom on the same zone as the bedroom; most people like a cool bedroom, but a warm bathroom.

Yes, it is possible that the cooler master bedroom air is activating the second zone thermostat more than it needs to be. Closing the bedroom door should take care of this.

Q. I live in western Pennsylvania and have a well-insulated house with R-39 in the attic, but I sometimes still get ice dams. Last winter when it stayed well below freezing, I had none, but they happen when we have thaw and freeze days because the sun heats the snow on the roof causing it to melt and refreeze when it reaches the overhang, which is still below freezing.

A. The ice dams you encounter from externally caused snow melting should not grow very big or cause serious problems because they are also likely to melt as temperatures moderate and the sun warms them up.

Unless you have noticed some problem, such as leakage inside, I think you needn't worry.

• Henri de Marne was a remodeling contractor in Washington, D.C., for many years, and is now a consultant. His book, "About the House," is available at www.upperaccess.com and in bookstores. His website is www.henridemarne.com. Readers can send questions to Henri de Marne's email address at henridemarne@gmavt.net, or to First Aid for the Ailing House, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.

© 2014, United Feature Syndicate Inc.