Posts Tagged ‘stress’

Problem With Wall – Unstable Paint

October 22, 2019


Here’s where a little bit of paint has peeled away from the wall. Why? Most likely because over the 60 year lifetime of this house, various products have been applied to the walls.

Oil based paint, followed by latex paint, then gloss paint, maybe some smoothing compound, then more paint and then another coat of paint.

In all probability, improper prep, or, more likely, no prep at all, was done between all these surface treatments.

The thing is, all of these disparate materials are not likely to stick to one another, especially if no prep has been done.

The problem becomes, then, that when a new surface treatment (paint, wallpaper) is applied, and then dries, which results in shrinking, which results in pulling taught and putting stress on the wall’s surface, the stress can cause these various surfaces to actually pull apart (delaminate).

That’s what you’re seeing here.

Potential Trouble Brewing

July 7, 2019


What you see here is a bit of rubbery latex paint and texture that has peeled away from the wall in this powder room. The surface underneath it felt gritty and dusty and porous. I had the feeling that if I had tried, I could have peeled all the paint off the wall.

This is not good.

This paint is probably peeling because of a combination of poor quality materials (cheap paint), improperly prepared surface (inappropriate or no primer, not removing dust from the wall, incompatible coatings (latex over oil based, not sanding or deglossing a gloss paint before repainting), climate fluctuations (humidity, temperature), stress on the wall (pulling off a piece of tape), or more.

All this is not so bad under paint, because paint just kinda sits there on the surface. But wallpaper actually puts stress on the surface beneath it, as it dries and pulls taught. Over time, fluctuations in humidity and temperature can exacerbate that, causing the paper to expand and contract ever so slightly, and then put tension on the wall where the seams fall.

This can result in not just the seams coming loose, but in the various layers inside the wall actually delaminating and coming apart from themselves.