Posts Tagged ‘white line’

Helping To Hide Seams

January 23, 2021

Like most wallpapers, this Sure Strip by York can be expected to expand a bit when it becomes wet with the paste. Once it’s on the wall, it will dry and give up moisture – and that results in a tad of shrinkage. That usually means you might see just a teeny bit of a gap at the seams.

Not usually a big deal. But when you have a dark or bold color such as this on a light background and also printed on a white backing, if the paper shrinks and gaps, you can end up with a hairline’s breadth of the underlying wall surface and / or of the white wallpaper substrate showing through.

Layman’s terms: You might have a slight white line showing at the seams.

To help ward this off, I did two things. One was that I used red chalk to lightly color the edges of the wallpaper. Sorry, I forgot to take a picture, but you can Search here to see previous jobs where I employed that method.

The other thing was to stripe red paint under where the seams would fall.

This is a bit more complicated than it sounds. Because wallpaper will stretch when it gets wet with paste, making it difficult to guestimate exactly where the seam will fall, and thus where to run your red stripe.

Once you plot that out, you need a level to guide you by creating a plumb line at the appropriate point. And then mix your paint with water and use a brush or small sponge to run along that plumb line, straddling it widely enough to catch the seam wherever the gap might end up actually falling.

Also, the red paint needs to be good and dry before you put wallpaper on top of it. So this means you run the red stripe down the wall, and then get fans or a heat gun, or employ some other method to get the paint to dry quickly.

Oh, and … wallpaper works best when it’s hung on a wallpaper primer. Primers specific to wallpaper are designed to resist the tension created when wet wallpaper dries and shrinks a tad, putting stress on the seam area.

By running paint on the wall along the seam line, now you’ve covered up the wallpaper primer. There is no way to know if that perfectly pigmented craft store paint will hold up over the long run and keep the wallpaper seams tight to the wall.

That’s one reason I used a fairly light mix of the paint. A full-strength concentration of red paint might not allow the wallpaper paste to grip onto it. And definitely do not use a glossy paint. Nothing sticks to gloss.

As you can guess, this process adds a significant amount of time to your install. But it’s worth it, because, in the red room I hung pictured in previous posts, the seams were virtually invisible. I know that if I had not colored the edges of the paper as well as the wall, white would have shown just a teensy bit at the seams.