If you'll be involved in the restoration of a house that has been badly damaged by damp, you should keep the following advice in mind.
Check the condition of the wall plaster before painting or wallpapering
Pervasive dampness in a house can destroy its wallpaper and wall paint. The condensation created by this issue can, for example, lead to the deterioration of the adhesive that binds a sheet of wallpaper to a wall, which can then cause the wallpaper to fall off.
The black mould that grows as a result of this condensation can also ruin the appearance of wallpaper. Additionally, dampness can cause paint to crack and peel off walls.
If the paint and the wallpaper in the house you are repairing has been ruined by dampness, it is important to check the condition of the wall plaster before you begin to repair this cosmetic damage.
The reason for this is as follows; if the plaster is still damp and you don't replace it before adding new wallpaper or repainting it, the plaster will eventually crumble and the moisture it is retaining will permeate the new wallpaper or paint you place on top of it.
As such, you should examine the plaster first. If it feels damp to the touch, or if there are visual indicators of damp-related damage (such as swelling and crumbling), you should find a tradesperson that performs plastering work and arrange for them to pull out this old plaster and replace it.
Tread carefully when working upstairs
If you need to carry out repairs in the upper storeys of the building, you should proceed with great caution.
The reason for this is as follows; it is possible that the dampness within the house may have inflicted damage on its wooden floorboards and joists, as long-term exposure to moisture often causes wooden items to rot.
If some sections of the floors in the upper storeys have been damaged in this manner, they may not be able to withstand your weight.
This could result in, for example, a floorboard collapsing under you, and one of your feet then falling through the opening. This could leave you with a sprained or broken ankle.
If you happen to be wielding a dangerous piece of equipment (such as a drill or a circular saw) when this incident occurs, you could also lose your grip on this object and subsequently end up with several serious lacerations.
Given this, it is important to tread carefully when walking across a room (particularly if you are carrying heavy materials).
Walk slowly and test each floorboard (by pressing down on it with one foot) before placing your entire body weight on top of it. If it yields underfoot or seems to have a spongy, rather than having a rigid texture, it may not be safe to work in that room until after these damp-damaged floorboards have been replaced.