When it comes to installing wallpaper, I am often asked do you really need to line prior to wallpaper? And my answer is YES!
Lining paper is a very important process for a number of reasons, but I guarantee all will result in a far superior finish to the wallpaper installation.
Lining paper is good for minor imperfections in the plaster. You will still need to spend time filling, rubbing down and caulking prior to Lining, but a smooth surface will be created. I personally opt for a 1200 grade liner or wallrock.
If using paste the roll wallpaper, the paper will expands once pasted and soaked (check roll for required soaking time as this varies). But when given time to dry the wallpaper will pull back. If installed directly onto a plastered surface, this will cause an inconsistencie into the drying. For example, if the wall was previously painted and your decorator has done the required preparation with the filling and sanding you already have a various situation on the wall, the emulsion, filler and possibly bare plaster. All these will cause issues with drying so Lining paper will create uniform drying time.
If you fail to spot staining on a wall, when you hang your lining paper it will become obvious. You can then either remove the liner and deal with the issue or if its and old stain you can apply blocking solution to the paper.
Mapping often occurs on previously papered walls. When stripped it could cause damage to the plaster, removing old paint in patches or damaging plasterboard. If you apply finish paper directly to these surfaces once dry, you will notice dark patches blotted on the paper, like a map. This would not occur if liner had been used.
The cost of lining
If you recieve a quote that includes lining and it is double to that of one that doesn't, do not feel you a getting ripped off! All the issues above can be addressed via lining. Generally lining paper will cost £7 for a double length roll, a finish wallpaper can cost £70+ roll (I once hung a £300 roll of wallpaper and there was more than one roll)! So ask yourself would you rather encounter these issues on a lining paper or a finish paper? If you instructed you decorator to install without lining, you will be at fault.
Wallpaper has seen a resurgence and like all trends it'sback! It is a luxury and can add character to a room. Never cut corners and always take your time with preparation