Posts Tagged ‘adhesion’

Paint Pulling Off Wall Where Tape Was Removed – Surface Stability Test

May 12, 2021
Paint pulling off wall where tape was removed.
Paint pulling off wall when painters tape was removed.
Paint pulled off wall and stuck to back of tape that was pulled off wall on new construction site.

It’s important to have a stable surface under wallpaper.

That’s because, when wallpaper gets wet with paste, absorbs moisture from the paste, and it expands. Then, as it dries, it lets go of the moisture and shrinks. When wallpaper dries and shrinks, it puts tension / torque on the walls.

If the surface under the wallpaper is not stable, the tension of the drying wallpaper can cause the underlying surface to pull away.

This photo is not showing the wallpaper pulling away from the wall. What is happening (usually) is that the paint (or whatever has been applied to the wall), has actually delaminated (come apart) from the wall.

This results in a “curled” seam, or a “popped” seam.

One way to test for this is to apply a strip of tape (blue painters tape, tan masking tape, clear Scotch tape, or other), let it sit a few minutes, and then yank it off. If the tape takes any paint along with it, you have a potential problem of the wallpaper not adhering correctly.

This is why it’s important to:

1, Before applying any coating, you must remove all dust from the wall, using a damp sponge, which must be rinsed frequently

2, Before hanging paper, a primer formulated specifically for wallpaper should be applied / rolled on and cut in to edges

A wallpaper-specific primer is designed to withstand the torque put on the wall as wallpaper dries. And it facilitates installation by allowing sufficient “slip” (maneuvering the paper) and “stick” (adhesion). The chemistry behind all this is fascinating – but too complicated to get into here.

If a wall is too “iffy,” and you don’t feel like the mess and expense of scraping off all the old paint, a liner can be applied before the actual wallpaper is hung.

A liner lessens the drying time of the wallpaper, which reduces the time there will be stress on the wall. A liner also redistributes stress on the wall, so much less chance of having seems detach from the wall.

A liner also adds additional cost to the job – for both material and labor, which may include an additional day(s).

Textured Wall Now Nice and Smooth

May 11, 2021
“Orange peel” texture on wall
Same wall smoothed and primed and ready for paper

You don’t want to hang wallpaper on a textured wall. The bumps will show through and look bad. Plus they impede good adhesion.

I’m pretty darned good at smoothing textured walls, through the skim-floating or skim-coating procedure. You can do a Search here to read more.

Note: The slight texture in the second photos is from the roller that applied the primer. The photo is magnified many times. In real life, this wall is nice and smooth and ready for wallpaper.

Repairing Damage from Remodeling

March 5, 2021

I hung this paper in a little boy’s bedroom about two years ago. Now a new baby is coming, so Son #1 is moving from the nursery to his “Big Boy’s Room” next door. In the process of the shuffle, the parents had the connecting Hollywood bathroom updated, and this involved moving a door – which meant messing up the wallpaper.

As you can see in the top photo, instead of taking the time and effort to remove the wallpaper, the workmen put their patching compound right on top of it. I don’t like hanging paper on top of paper, for many reasons. There are adhesion issues. And also, for one thing, it’s not good to have seams fall on top of seams. For another, because the new paper is somewhat thick, you would have a visible ridge from top to bottom along the edge of the new strip.

So I took a razor knife and cut roughly around the workmens’ patch. Then I stripped off the paper around it, up to the edge of the adjoining strip. I did this on both sides of the corner.

This wallpaper is of a non-woven material, and is designed to strip off the wall easily and in one piece when it’s time to redecorate. I was pretty disappointed that that turned out to not be the case.

On the other hand, I was happy that it didn’t. Stripping paper that way puts a lot of stress on the wall surface, and you can end up with delamination (coming apart) of various layers under the paper (primer, skim-float, paint, drywall).

So I used a more labor-intensive, but lower-impact method. Click my page to the right for more info on the process. I first stripped off the top, inked layer of paper. That left the white backing still adhering to the wall. I used a sponge to apply plenty of water to this backing. The idea is to reactivate the paste that is holding it to the wall. Once that paste was wet enough, the backing pulled off the all cleanly and easily.

I was really pleased that my primer from the original install held up perfectly under all this soaking and tugging. I had worried that it might “rewet” and pull away from the wall, which had been my experience with it before. I had used Gardz, a penetrating product designed to seal torn drywall. It’s also good at sealing new skim-coated walls. And wallpaper sticks to it nicely, so all the better!

One photo shows you the stripped off area next to the edge of the remaining strip. You can see the thickness of this existing strip. The new wallpaper will butt up against this, and there will be no ridge because the thicknesses of both strips are the same.

Another photo shows my stripped-off area next to the contractor’s patched area. There is a difference in height between the newly revealed wall and the patched area – and that will show as a ridge or bump under the new wallpaper.

To eliminate that difference in height, I skim-floated over the area. In one photo, you can see the wet (grey) smoothing compound. I set up a strong floor fan to assist in drying. My heat gun also came in handy.

Once it was dry, I sanded it smooth. Now you don’t see any transition between the newly exposed wall and slightly higher patched area. I applied Gardz to the all the newly patched areas. Set up the fan again. And once it was dry, I put up the replacement paper.

It’s a good thing the family had paper left over from the original install. If they had had to purchase new paper, it could have come from a new Run (slight difference in color shade), and that would have meant stripping off and replacing three walls.

We had barely enough paper. The corner was out of plumb by as much as 1/2″ from floor to wainscoting, on each side of the corner. That adds up to an inch out of whack. That one inch meant we needed a whole new strip of wallpaper, to get the paper on the wall to the left to match up with that on the wall to the right.

Long story short, the whole thing turned out great. There is a bit of a mis-match in that corner, but it’s not very noticeable at all.

The wallpaper is by the Scandinavian company Boras Tapeter.

The home is in the West University neighborhood of Houston.

William Morris “Fruit” in Historic 1885 Home

December 20, 2020

Moving from the entry to the adjoining dining room of the historic home in Houston mentioned in my two previous posts. This pattern by William Morris is called “Fruit,” and is true to the period in which the home was built.

I love the way the colors work with the wainscoting and also the picture rail around the top.

This pattern is less repetitive and the color is softer than the option used in the entry (see yesterday’s post), making it an easy-to-live-with choice for this large dining room.

The material is a traditional British pulp which you don’t see much these days, as most European manufacturers have moved to the newer non-woven substrates. I do like the pulps for their matt finish and tight adhesion to the wall. Although, they are brittle and tend to drag and tear when being cut, so they require some special handling.

This one also has a raised ink feature, which adds just a tad of texture. Look closely at the close-up shot.

This was purchased from FinestWallpaper.com, who has a large selection of Morris and also Voysey (another designer from that Arts & Crafts period) patterns. The home is in the Old Sixth Ward neighborhood in central inner-loop Houston.

Smoothing Suburban Heavily Textured Walls

November 1, 2020


In the tract homes in new subdivision developments all around Houston, it’s very common that the builder will use a heavy wall texture like this. You can’t hang wallpaper on this, because the bumps and dips will look horrible under the paper, and also they will impede good adhesion.

So the walls will need to be smoothed. This is accomplished by “skim-floating” or “skim-coating” the walls with joint compound. I do my own prep. And, as I like to say, I’m better at it than any “guy” you can hire. 🙂

The third photo shows the wall with half in original condition, and half with the smoothing compound applied over it.

Some people use a wide taping knife to spread the “mud,” as we call it. But I prefer the trowel shown in the fourth photo, because I am closer to it and can see everything that I am doing, and also I feel the position of the handle gives me better manual control.

Sometimes, using fans and playing with the A/C or heat systems, the compound will dry in a couple of hours. But with texture this heavy, the material must be left to dry overnight.

Tomorrow morning, I will sand the walls smooth, vacuum up the dust, wipe residual dust off the wall with a damp sponge, and then roll on a primer. Once that dries (again, call in the fans!), the wallpaper can go up. The second-to-last photo shows it finished and ready for wallpaper.

The last photo shows the brand I prefer, USG’s Sheetrock brand “Plus 3,” which you can find at most big box stores and most paint stores. It sands a lot more easily than the standard joint compound in the red, white, and green box.

This Worries Me – Mildew??

July 8, 2020


These little specs of brownish red, and also circular patterns of a powdery grey/black substance, were dispersed throughout the backing of the Serena & Lily grasscloth I hung today.

What worries me is that they look like mildew that I have encountered in homes that have moisture problems. And mold and mildew can work their way through wallpaper, causing discoloration, and even interfering with adhesion.

Possibly the factory is not climate-controlled, and mildew was able to get a foothold on some of their product??

Let’s hope that my worries are unfounded. Only time will tell.

Smoothing Sand-Stippled Walls

October 13, 2018



The texture on these walls in a powder room was an odd combination of “orange peel” and sandy grit – neither of which was suitable for under wallpaper, because the texture would show through under the paper, and because the texture would prevent good adhesion of the paper to the wall.

So I skim-floated the walls to smooth them. Because the texture was so thick, I had to use a space heater, multiple fans, the home’s A/C and house fan systems, and an overnight dry time, to get the smoothing compound to dry. The next morning, I sanded the walls smooth.

In the second photo, you see the finished, smooth wall.

Smoothing a Textured Wall

June 16, 2017

Digital Image

Digital Image

Digital Image


The bumps on textured walls (see top photo) will show under wallpaper and look horrible, and the texture also impedes good adhesion. So I “skim-coat” the walls with joint compound (“mud”), which is much like plaster, let dry, and then sand smooth (see middle photo).

The walls need to be sealed before wallpaper can go up, and for this, I like Gardz, a penetrating sealer that soaks into the surface, binds everything together, and dries hard. It’s also a wonderful primer to hanging wallpaper on.