The walls in this powder room in the West U neighborhood of Houston had had many treatments over it’s life, including paint, more paint, skim-floating, wallpaper, and more. Sometimes, and particularly if prep is not done properly, these various layers are not compatible, and won’t adhere to one another well.
When the old wallpaper was removed, this was clear at the seams, where the various layers of the wall had pulled apart, leaving ridges along the length of each seam. This happens because the wallpaper dries and pulls taught and creates tension on the wall; if the wall is unstable, the layers can be pulled apart (delaminate). Sorry, no pics of the “before,” but you can do a search here to see pics of other rooms. This condition can happen over time, as the house fills with humidity and the paper absorbs it, then dries and shrinks again.
I dug out the raised ridges and applied tape over them, sealed with Gardz, a penetrating sealer that dries hard. Then I skim-floated over all the walls, to create a smooth surface for the wallpaper. Sanded, wiped dust off with a damp sponge (nothing sticks to dust), and primed all walls with Gardz.
One good way to deal prevent this from happening again is to cross-line the walls with a special liner paper. This is a thin paper that is usually run horizontally before the actual decorative paper is hung. The idea is that if the new paper shrinks and applies tension, it will be distributed by the liner paper, and will not pull at the wall. If the liner shrinks and pulls, the tension is off-set by the decorative paper on top of it. So the two layers are working together to distribute any harmful tension on the wall surface.
Unfortunately, using liner adds a day of labor plus the cost of the material. The homeowner’s budget had already been busted by other factors, so she wanted to keep the job to one day. After collaborating with my colleagues in the Wallcovering Installers Association on our Facebook page, I decided to try this method:
From Office Max I got some plain old cash register tape. I plotted where each seam would fall, and used my laser level to guide placement of a floor-to-ceiling strip of the tape. I adhered it with regular wallpaper paste. At first, I worried that it would soak up moisture and bubble, but once it was smoothed into place, it laid down nice and flat.
Then I hung the wallpaper. The seams fell nicely on top of the tape, held tightly, and looked beautiful. There is the possibility of seeing a very slight ridge under the paper because of the thickness of the tape, but it’s very minimal because the tape is quite thin. And it’s much preferable to popped seams or delaminated walls.
The idea is that the tape will bridge the seam, and distribute tension from the drying paper across the width of the tape, keeping tension away from the wall itself. The tape is very thin, and doesn’t appear to have much tensile strength, but my buddies who have tried this method say it works well.
Time will tell, but I have a lot of confidence in this method.
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