TREATMENT OF DAMP WALLS.
There are two classes of damp walls, first where the water comes in from the outside from defective roofs, bad gutters, defective pipes, and where it comes through the walls from the ground, as in basements. In the other class we may include walls which are dampened by condensation of moisture, in places shut off from the general artificial temperature of the room, behind stationary furniture. Such walls may dry out during hot weather, or they may be kept damp by a growth of mold or fungus.
When water comes in from the outside, it is impossible to keep paint or paper on the wall in good shape. Look around for the places where the water comes in, point it out to the owner, and if he fails to stop the leak have it understood that the work is done at his risk; or, what is better, refuse to do the work; because, when a job comes off, or turns out badly, you will take the blame generally, no matter whether it is your fault or not. A job may be made to last awhile by a waterproof coating, or by sheathing with thin lumber, but it is only a question of time when the lining material will become water-soaked and spoil the paint or paper, to your discredit. I have usually been too busy to take jobs of this kind. If the water can be cut off, the next thing is to dry the wall, which you can do at the surface only by setting a stove near it, or with the flame of a paint burner; then, after all your trouble, the water, which remains in the wall, if of brick or stone, may find its way to the surface, and destroy your work. Sheet lead cemented to the wall will answer a good purpose for a time, but the dampness will finally destroy the cement and let the metal loose.
Battening out for lath and plaster is the best for basement or damp stone walls, but that is the plasterer’s work, and is rarely ever done except in private residences.
Battening and canvasing is next best; nail your battens up and down 18 inches apart. Have the canvas stitched in sheets the right size to cover the large blank spaces of the wall. Then stretch and tack it on the battens, and give it a coat of glue and alum size.
When dampness is caused by condensation the best remedy is to remove the cause and dry the wall.