Sometimes (usually) wallpaper expands when it gets wet with paste and then shrinks just a tad when it dries. This can result in hair-breadth gaps at the seams. Usually not a big deal. But when the paper is dark and the sub-surface is light, you can end up with white wall visible at the seams. So sometimes I’ll paint a stripe of matching color behind where the seams will lie. Measure to plot where the seam will fall, then use a level and pencil, or a laser level, to indicate where, and then run a stripe of paint along that line. Make the stripe wide enough to accommodate slight variations in measurements and wallpaper expansion. I use craft paint from the hobby store or Texas Art Supply. The photo shows an outdoor paint – not the best option, but it’s what I had in the truck. 🙂 I use a small rectangle of sponge dipped in water and then in the paint. For extra assurance, on thick papers, dark surface printed on a white backing, you can also use artist’s chalk pastels (chalk only and NOT oil pastels) to color the edges of the seams. Do a Search here (upper right corner) to find previous posts about that.
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