M. G., Cleveland, O., writes:

"Each winter we have great trouble with our pipes for conducting the storm water from the roof to sewer. They seemed to begin to freeze at the foot of the pipe, after some stoppage which we cannot account for, as we keep our roof clean. They will then fill to the top of the pipes, overflowing and forming threatening and dangerous icicles, or making a disagreeable dripping, generally most annoying in the afternoon. Each spring we have to replace those pipes or pay large repair bills, many of the seams and joints being found burst. Our roof is of tin with a pitch of one-half inch to 1 foot. Our engineer suggests that we write you on the subject in the hope that you may suggest a remedy."

[Your complaint is a very common one in cold climates, and is especially common in New York in the winter. The fact that the dripping begins generally in the afternoons is because by that time the steam heat in your building (we assume you have steam heat, as you refer to your engineer) has begun to affect the snow and ice on your roof by passing through the wood sheathing and tin, which have been frozen hard by the colder air of the night. This action is accelerated by the sun's rays, if the temperature is above the freezing point.

If unobstructed, the water will fall through the conductor pipe to the sewer or outlet, as it cannot freeze while in rapid motion, or when the air is at a temperature that will allow of thawing. Here this water comes in contact with the cast-iron or earthen sewer pipe imbedded in the earth or stone sidewalk, which is surrounded by all the influences of frost, and which has the nucleus of an ice formation in the hoar frost on the inside, the result of warmed damp air ascending and condensing its moisture, which is readily frozen. This operation continues until the pipes are entirely closed. Then the pipe will gradually fill to the first relief point, and if the pipe has been made perfectly tight it will freeze to the top. The practice of making these pipes tight is wrong, as loose fitting joints united only, will allow the water to escape when it fills to them.

The most certain and direct cure for your trouble would be to have large conductor pipes placed on the inside of your building, where they will be removed from the influences of frosty blasts or frozen outlets. But in this case it should be of extra-heavy cast-iron pipe with leaded joints to prevent sewer gases or odors from entering the building. This is the practice adopted for public building and business structures. The pipes should be in recesses and accessible for repairs.

If you cannot change your conductors, see that the snow is removed from the roof before it has had time to freeze to the tin. This will help you, save when there is a cold rain or sleet storm. A sure method to keep the pipes open without regard to the severity of the frost is to enter a steam pipe with jet end at the lowest accessible point of the leader, arranged with a swivel joint, so that the jet may be turned up when desired to clean the pipe, or downwards when not in use, when it will not become filled with water and freeze. A valve at a convenient point under the charge of your engineer will enable him to use it as his judgment dictates in thawing the ice or frost.]