RE-PAPERING, TREATING DAMP WALLS, ETC.
In re-papering it is desirable, though not ab solutely necessary, that the old paper should be stripped from the walls. If it is decided to leave it on, rub down the joints of overlapping blocks. if any exist, with glass-paper; do any necessary stopping, then give the walls a coat of strong size. When dry, re-paper in the usual manner.
Paper is stripped off by damping it with water until the paper will come off without diffi culty. Give the walls a thorough rinsing down with clean water so as to get rid of all old paste and size. It is desirable to wash the walls with an antiseptic, such as carbolic acid.
Before papering old ceilings, they should, after being cleaned, be coated with a solution of strong glue size and whiting, which must be al lowed to dry thoroughly.
Before papering a painted wall, first wash it with strong soda water, rinsing well with clean water, and, when dry, rub down with glass paper. The walls should then be papered with a good lining paper, using glue with the paste. When dry, rub down the joints, and paper in the ordinary way.
In replacing the damaged paper on the walls of a large room, there is the defect that the new paper is lighter than the old.
The success or failure of any attempt to darken the new paper will depend on the char acter of the paper, and whether the colors and ground can be altered without injury. In the case of a flock or any light paper that would not bear sizing, the work could not possibly be done. If the paper can be brushed over with weak, clear size in order to fix the colors and protect them, a second coat of size stained to match the old paper might perhaps be applied. The col ored size should be stippled on whilst the first coat is wet; or the marks of the brush will show. The greatest care will be required in order to match the tone of the old paper and obtain an even surface. A piece of the new paper should be darkened before it is hung on the wall, in order to ascertain whether the paper can be sized without disturbing the pattern.
Walls are tested for dampness before prepar ing by means of gelatine strips. The thinnest procurable pieces of ordinary sheet gelatine are soaked in water until they are quite soft; they are then spread out flat on a greased sheet of glass, and stretched with the fingers until all folds or creases are smoothed out, and the sheets are made as thin and uniform as possible. They
are then dried in the air, rough or uneven edges trimmed off, and each sheet is cut into strips about 4 in. long and 2 in. wide. These strips should be kept in a dry place, as they are very sensitive to moisture. The gelatine strip is passed slowly over and as near as possible to the surface of the wall but without touching it. Any dampness that exists in the wall is immediately indicated by the curling of the gelatine.
When it is necessary to paper walls while they are still damp, a coating of tinfoil or of im pervious paper is first applied, while for ordi nary work the paper may be coated with pitch. Tinfoil, of non-rustable metal, is very satisfac tory in use, as, owing to its extreme thinness, it can be applied in patches without the fact being noticeable through the covering paper. Tinfoil is hung with paste in the same manner as paper; and sometimes, in order to counterbalance ally slight imperfection in the metal, the patch is given a coat of patent knotting (shellac dissolved in naphtha).
Another method of papering clamp walls is as follows: Thin veneer strips of beech or pine 3 in. wide are nailed to the wall horizontally and vertically about 3 in. apart. Jute canvas is then stretched over the surface and nailed to the wood strips. This canvas is first covered with waste paper, and then with the wallpaper.
When damp places are entirely due to a cause which has been removed, it would be as well to let the walls dry naturally before re-papering them.
The oven side of a fireplace if of stone and constantly hot is generally painted instead of papered on account of the difficulty in getting the paper to stick fast. However, a mixture of equal parts of powdered gum arable and plaster of Paris might make the paper adhere; keep it in its dry state and mix it with water when about to use. Glue has also been advised.