Wallpapering isn’t as difficult as it looks once you are equipped with the necessary tools. In addition to a paste table, brushes and some paste, you will also need shears, a spirit level, plumb line, scraping tools and sandpaper. Stairwells are the most problematic area and they are covered separately.

Calculating the Number of Rolls

To calculate how many rolls you need to buy, get hold of a wallpaper-calculating chart, readily available from most DIY stores. Measure the height of the walls from skirting board to the ceiling, coving, picture or dado rail (depending how far up you intend to cover) and the perimeter of the room. (Don’t deduct anything for the areas covered by doors or windows, unless there is a large picture window or patio door.) On the chart, find the measurement nearest to the perimeter of your room in the left-hand column then read across to find the height of the room in the right-hand column. There you will find the number of rolls required for a plain wallpaper.

If the wallpaper has a pattern you may need to take this into account. A large pattern repeat requires more paper than a random or non-matching design, which doesn’t need to be pattern matched. The best bet is to buy an extra roll on a sale-or-return basis, so that if you don’t need to open it, you will get your money back. Check when buying that the batch number printed on the label of each roll is the same. Even then, a slight difference in shading is possible, so you need to unroll all the paper at home and examine the colours in a good light. If any of the rolls are of a slightly different shade, don’t hang them on the same wall, where the difference might be noticeable.

Preparing The Walls

Before you hang the wallpaper, prepare the walls in the same way as for painting. However, where the old plaster is sound but badly crazed, or has been repaired in places over the years, it is best to hang lining paper first, as this will prevent defects showing through the wallpaper. Lining paper is usually hung horizontally, to prevent the joints coinciding with the wallpaper.

Any existing wallcovering must be stripped off completely. Some papers can be stripped off in lengths simply by loosening the bottom edge and pulling upwards. This leaves a thin backing paper on the wall which should be wetted then scraped off. Other wallcoverings may need to be soaked with water before scraping them off. Adding a little wallpaper paste or washing up liquid to the water helps the soaking process, making the stripping easier afterwards. Some vinyls and washable wallcoverings will need to be scored first, to allow water to penetrate the old paste.

If you are faced with a really stubborn wallpaper, or more than one layer, you can save time and effort by hiring or buying a wallpaper steam stripper. This produces steam through a square plate that loosens the paper when it is held against the wall. It’s a great labour-saving device and quite inexpensive to buy these days. Recently some clever cookie invented a handy little tool called an orbital scorer, which you simply run over the paper in a circular motion, creating little pin holes that allow the moisture from the steamer to penetrate behind the surface. After doing this, use both a broad-bladed and narrow-bladed scraping knife to carefully remove the old paper without damaging the plaster behind.

When all the paper has been stripped off, rub the walls down with sandpaper to remove any little nibs of paper still clinging to them.

Porous walls have to be ‘sized’ to ensure that the wallpaper adheres properly; sizing has the added bonus of making it easier to slide the paper into place when pattern matching across the lengths. Size can be bought purpose-made (a powder that is mixed with water) or you can simply dilute ordinary wallpaper paste, according to the manufacturer’s instructions. Brush size on to the wall and leave it to dry for a short while before hanging the wallpaper.