Paper Tearing
If the wallpaper is tearing when you try to pick it up to apply to the wall, or even when it is attached to the wall, you have probably used too much paste or the paste is too thin. Thicken up the paste and apply less to stop this happening. If the paper is tearing whilst cutting, check that your scissors or knife is sharp.
White Seams Visible
If, after applying the wallpaper, white seams or lines are showing between the sheets, you have either not butted the sheets together properly or the paper has shrunk as it has dried. Make sure sheets are butted together properly and roll the seam with a Seam Roller. Lining the wall with lining paper will also help stop this problem. It is also important to let the paste soak into the paper properly before hanging.
Bubbles
The occasional bubble in wallpaper is hard to avoid, but if you are seeing lots of bubbles, you are doing something wrong. To Prevent bubbles, check that you are not using too much paste and that the paste you do use is evenly spread. Also make sure you have allowed the paste to soak in properly. To remove bubbles in paper that has already been hung, pierce with a knife and allow excess paste to escape. If the bubble is air, pierce and flatten, brushing over with a small amount of paste on a brush. Sponge this down after a short while to finish.
Creases
Creases sometimes occur when hanging paper around or into a corner. Small creases can be treated like bubbles.
Seams Lifting
If you did not line the walls before papering, you might find that some fo the seams lift slightly. To fix this peel the seam back slightly and apply paste to the underside of the paper with a small brush (artists brush or similar). Press the seam back in place and roll with a Seam Roller. Wipe the seam with a sponge to remove any paste from the surface of the paper. It is, however, always better to line your walls before papering.
Paper Lifting
Again, this could be because you did not line the wall. It could also be caused by the residue of distemper (an element found in some paints). If you think this might be the problem, remove the paper from the effected area and wash the wall well. Allow it to dry and then rehang the paper.
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