Posts Tagged ‘expanding’

Weird Cracks

March 24, 2020


I have just finished stripping off wallpaper that I hung 12 years ago. The walls beneath are in perfect condition.

Except that, along just about the full height of just about every seam, I discovered these hairline cracks.

What is very odd is that the cracks have not made the wall unstable, and no material has pulled away from the wall (as often happens when you have layers of incompatible materials that will not adhere to each other – do a Search here on “delaminating”).

I believe that my original prep 12 years ago was to skim-float the walls and sand smooth. Then I wiped off the dust with a damp sponge, then followed with my favorite primer at the time, KILZ Original oil-based primer.

My thought is that the KILZ, or possibly the underlying joint compound, has separated due to tension put on it by the wallpaper seams, possibly shrinking and expanding over the years due to minute fluctuations in humidity and temperature.

Why that happened I don’t know.

This past year, I’ve had opportunity to remove wallpaper from several jobs that I hung as far back as 20+ years ago. All were over the very same original prep conditions. But none showed these little hairline cracks.

I always like to understand why something happens. That way, you have the potential to prevent it from happening in the future.

Not that I’m particularly concerned in this case. The tiny cracks have not created any problems, and the wall is not unstable.

I felt perfectly comfortable hanging the new paper right on these walls – however, I made very sure that no seams of the new paper landed exactly on top of those cracks. That would eliminate the chance of any stress put on the cracks by the new seams potentially causing them to weaken and pull away from the wall.