DEAR BARRY: We have a major problem with drain flies under our house. We’ve called a plumber and an exterminator, but both say they’ve never seen this kind of problem before. We’ve also had the septic system pumped and inspected, but this doesn’t seem to be the source of the flies. What should we do? –Tracy
DEAR TRACY: Your exterminator should know about drain flies. These pests breed in the soft, organic matter that coats the insides of drainpipes. To get rid of them, you must thoroughly remove the slimy residue in the pipes. This cannot be done with common drain cleaners, nor with boiling water or bleach. Instead, there are special products called "drain gels" that are specifically made for this type of drain cleaning. But before using drain gel, solid residues such as hair should be purged from the drains. For this, you should hire a plumber to snake out the lines.
Keep in mind, however, that drain flies can be breeding in other locations where there is rotting organic matter, such as moldy drywall or discarded food waste. In some cases, spillage from an open waste line under a home can provide the environment needed by drain flies.
To determine if the flies are originating in your drains, there is a tape test that you can do. For several consecutive nights, place a piece of duct tape across each of your drain openings, with the sticky side down. Do not cover the entire opening with the tape. Just run a strip of tape across the center of the orifice and leave the sides open. If the flies are breeding in the drains, some of them should be stuck to the tape in the morning. Hopefully, the drain is the source. Otherwise, you’ll have the job of searching for other places where breeding might be taking place.
For further information about drain flies, visit http://www.pestproducts.com/fliesdrains.htm.
DEAR BARRY: I am presently in escrow to buy a home, and the mortgage company requires that I buy flood insurance. This must mean that there has been flooding at some time in the past, but I see no evidence of water damage anywhere on the property. So I’m wondering, how serious can the insurance requirement be? Is there any way to find out if the house has been flooded, and if so, what was the extent of the damage? –Kathleen
DEAR KATHLEEN: The requirement for flood insurance does not mean that the house has been flooded in the past. Mortgage companies typically base flood insurance requirements on the location of the property, not on its flood history. If a house is situated in a geological flood plain — that is, if there is the possibility of flooding every 100 years — then flood insurance is usually required. In some cases, a property that is partially in a flood plain will require flood insurance, even if the home is on higher ground and not located in the flood plain.
You should check with the county engineering department to determine whether the home you are buying is actually located in a flood zone. In some cases, it is possible to negotiate these insurance requirements with the mortgage company.
To write to Barry Stone, please visit him on the Web at www.housedetective.com.
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