Posts Tagged ‘oil based’

Danger Signs of an Unstable Wall Surface

October 13, 2021
These nails were holding picture hooks to the wall. The hooks had an adhesive backing. When they were removed from the wall, chunks of latex paint stuck to them and pulled away from the wall, revealing a crumbly sub-surface. This is bad news for wallpaper that might be hung on top of this.
Other spots. What happens is, this is a 90 year old house. Over the years, many coats of paint and other surface treatments have been applied to the walls of this dining room. These coatings are not necessarily compatible with each other. Plus they may have been applied without the proper surface preparation. Oil based paint, then latex, then someone rolls on a gloss paint, the next guy follows with latex but neglects to de-gloss the previous layer so the new layer doesn’t really stick well.
Somewhere along the line, something got chalky. Here you see I have wiped crumbly chalky substance from inside the wall. This is why the latex paint is not adhering well and pulled away so easily. Nothing sticks to dust or grit or chalk.
Gardz is cool stuff. It’s a penetrating sealer that soaks in and actually binds crumbly materials together, drying into a hard, solid mass. The problem here is, it won’t penetrate the paint that is on top of the unstable layer, so we’re still dealing with a wall that has potential to come apart (delaminate).
Gardz applied. You can see how it has soaked into the porous areas, but is sitting on top of the latex paint.

The problem with an unstable wall and wallpaper, is that, as wallpaper sits on a wall and the paste dries, the paper shrinks just a tad, and this shrinking puts tension / torque on the wall beneath it. Sometimes this is actually powerful enough to pull the layers inside the wall apart, resulting in seams that split open.

These are not “loose seams,” but the paper actually taking layers of paint and dust along with it. Really can’t be repaired.

So best to find a way to prevent it from happening in the first place. More on that later.

Candice Olson “Linden Flower” in Home Office

July 1, 2021
Before. Original chalkboard paint sealed off with KILZ Original to block any oil residue from chalk that might bleed through the wallpaper. Then primed with Roman 977 Ultra Prime wallpaper primer.
Finished. Airy, floral, fun place to work!
First strip goes up, lined up against the red light of my laser level. I measured and plotted the placement so that the center of that dominant black flower would drop along the vertical center line of the wall (about 8″ to the right of the laser line).
Detail. I like the shadows in the background.
Close-up shows pen & ink, and water color look of this design.
Manufacturer is York, one of my preferred brands. http://www.yorkwall.com

Working from home these days, the homeowner wanted an office that was bright and encouraged creativity. The black chalkboard paint scrawled with slogans and proverbs had to go!

Almost exactly a month ago, I prepped the walls and started to hang the paper – only to discover printing and trimming defects. See my post from May 26, 2021. The on-line vendor, Burke Decor, was quick to ship out replacement paper from a different run. The new paper was fine.

The new light sconce plays off the black and gold colors in the wallpaper.

This refreshing yet peaceful abstract floral pattern sets the perfect tone, when your office is in your home.

The home is in the Heights neighborhood of Houston.

Rust From Water Damage Will Stain Wallpaper

August 11, 2020

Look to the right of the can. Notice the tiny spots of red. This is rust, and rust is bad because it (along with certain other substances, like ink, tar, oil, tobacco, water stains, wood sap (knots), mold, mildew) will bleed through wallpaper. Maybe not immediately, but, over time, it will work its way through the primer and the paper and to the surface, leaving a spot that cannot be washed off.

Actually, there was a whole lot of rust along the entire height of this wall’s corner. An air conditioning leak had kept the drywall wet for a period of time, and rust had formed along much of the metal corner – called a “bead.”

I skim-floated over the affected area with joint compound, and that buried the rust … for a while. But rust (and other substances), will eventually work their way to the surface, leaving spots on the wallpaper.

So a stain blocker was called for, which will prevent any stains from bleeding through. For this I love KILZ – but only the “Original” oil-based version. The water-borne products just don’t measure up

Some reasons I skim-floated over the area was to provide a buffer space between the rust and the sealer in hopes that the rust would not make it all the way up to the surface, to create more material over the very corner itself that could soak up the sealer, and because the stain blocker would soak into the porous smoothing compound more so than to the sharp corner of the metal bead.

Mirror Tar Bleeds Through Wallpaper – Prevention

June 18, 2020



The owner of this newish home in the Woodland Heights (Houston) had her handyman remove the powder room mirror and its surrounding built-in wooden frame. Mirrors are often adhered to the wall with mastic, a tar-like substance. When the mirror comes off, some of the tar residue invariably remains.

In the top photo, you can see where removing the mirror took the blobs of mastic along with it, as well as round sections of the drywall. But there are small smudges of tar still remaining on the wall.

The problem is that tar (among a lot of other substances) will bleed through wallpaper (as well as paint, and a lot of other materials).

There are stain blockers like my beloved KILZ Original Oil Based, BIN shellac based, or others, that are designed to block these stains. But I don’t trust them. For water, rust, blood, wood sap, etc., yes. But for oil-based substances like tar, I want more assurance. The best way to prevent bleed-through is not to cover the stain, but to remove it.

So I take a Stanley knife and cut into the drywall and then peel up the top layer of drywall, taking along the offending tar residue.

So now the dangerous tar is gone. But you’re left with torn drywall. This is bad for several reasons. For one thing, you have an uneven surface that will look bad under the new wallpaper (or paint). And since the top, protective layer of drywall is gone, any moisture (such as from wallpaper paste or from latex paint) will penetrate into the torn paper layer – which will swell and cause bubbling.

All of which looks pretty bad under wallpaper or paint.

So I used the product Gardz to seal the torn drywall. It is formulated to soak into the paper; then it dries hard and acts as a sealer and moisture-blocker. It won’t block stains, but it will prevent moisture from penetrating the paper and causing bubbling.

Once that was dry, I skim-floated over the entire area with joint compound. It looks rough in the photo, but once it’s dry, I’ll sand it smooth. Then I’ll give it another coat of the penetrating sealer Gardz. See last photo. Once that is dry, I’ll cover it with a coat of Roman’s Ultra Prime Pro 977 wallpaper primer, when I prime the other walls in this powder room.

All of these various products do take a while to dry, especially the joint compound as thick as I applied it. So I went to this job site a few days before the install date, to do the initial prep, so it would have plenty of time to dry before I come back for the final prep and wallpaper hang.

Paint Problem

May 30, 2020


Hard to see, but the paint on this wall is crackling. This is most likely because there are unstable and incompatible layers of paint underneath.

In an old house like this (1940’s), there will have been many treatments to the walls over the years. Original oil-based paint, covered by latex paint, gloss paint, dust, more colors and layers of paint. And virtually never does the workman prep the walls properly.

Latex doesn’t like to stick to oil, and most paints don’t like to stick to gloss, plus other factors. So what happens is that all these disparate layers rebel, and sometimes you end up with flaking or peeling.

If wallpaper is applied on top of these unstable walls, when it dries and pulls taught and puts tension on the wall surface, there is the potential for these layers to give way, and you can end up with a curled seam, under which are layers of delaminated wall.

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.

KILZ Stain Blocker to Cover Green Ink

October 26, 2019


See the green vertical line to the right of the paint can? The previous wallpaper installer probably had a little white wall showing at a seam, so used ink that matched the color of the wallpaper to disguise it.

Ink (along with other substances, like blood, rust, water stains, oil, tobacco, mildew, wood sap, and others) can bleed through joint compound, paint, and wallpaper. Sometimes it takes a few months or years.

So it’s important to discover these stains, and to treat them with a stain-blocking sealer. Water-borne products simply don’t work, no matter what the label claims. Shellac-based sealers like BIN are good. But I like KILZ Original, the oil-based version.

20+ Year Old Paper – Still Perfect

July 31, 2019


I hung this paper in a master bathroom in Bellaire more than 20 years ago. It is still in perfect shape!

This is due partly to the good quality paper the homeowner chose (not low-end, pre-pasted, paper-backed, solid vinyl), to good ventilation removing humidity from the room, to good installation techniques, and to the great primer I used at that time – Oil Based KILZ Original. Unfortunately, EPA regulations forced changes to this primer, and wallpaper paste will no longer stick to it.

The homeowners are going to renovate and update the bathroom, so I was there taking measurements for the new room. When it comes time to remove this old paper, I know that it will strip off easily and cleanly, because of the installation and primer used when it was put up.

Replacing One Wall

April 13, 2019

I hung this sunburst medallion wallpaper in an entry in west Meyerland a year or two ago. Originally, there was a doorway in the middle of this wall that led into the adjoining room. The homeowners had the doorway closed off, and the opening was replaced with a new piece of Sheetrock. This needed to be covered with wallpaper.

New wallpaper could not be patched in, and the damaged areas along the wainscoting could not be readhered, so new paper had to be bought to cover the entire wall – as well as a section over the entry door.

The second and third photos show where the contractor had pulled the paper away from the wall. As you can see, it took some of the primer and the paint below it, too. I wish I knew what the contractor did to have this result, because when I stripped off the rest of the wallpaper, it came off easily and left the wall surface below it perfectly intact.

I suspect that he just yanked the paper, or possibly used heat or some weird chemical. The proper way to strip off wallpaper is to wet it, then separate the top, inked layer from the bottom, substrate layer, and pull the top layer gently off the wall. Then you take a sponge and bucket of water and wet the backing. Once that water reactivates the paste, the paper backing will come away from the wall easily and with little-to-no damage to the wall.

I also suspect that this paper was hung over KILZ Original oil-based primer, which was a superb primer because it stuck tight and because it was not affected or reactivated by the water used to soak the wallpaper backing. Unfortunately, the formula for that product changed due to EPA regulations, and wallpaper paste will no longer stick to it. These days, I’m using two alternative primers – both water-based, and I am curious to see how they hold up when wallpaper is stripped off them.

Back to today’s job … Once I got the paper off, I used joint compound (“mud”) to smooth over the uneven areas between the contractor’s stripping job and mine, then sanded smooth, wiped free of dust, primed, and then hung the new paper.

The wallpaper pattern is by Thibaut, and is called Bahia. It’s a non-woven product, and is designed to strip off the wall easily and in one piece when it’s time to redecorate. As you can see, neither the contractor nor I had success with that. The tried and true separate-the-layers-and-saturate-the-backing-with-water method was the solution.

Wall Prep – Missing Chair Rail and Stain Repair

March 31, 2019


What an unexpected surprise I got when I arrived at work to discover that the chair rail in this entry had been removed (top photo). Not only did I need to figure how to get enough paper to cover the additional wallspace, but I needed to smooth over the damaged wall area where the molding had been torn off. (See previous post)
I skim-floated the wall and sanded smooth. It looked great. But brown coloring from the torn Sheetrock had worked its way through the smoothing compound (second photo). Torn drywall is not something that I would normally worry about bleeding through wallpaper (you are concerned mostly with things like grease, ink, water, tobacco, rust, and the like), but this stuff was 60 years old, so who knows what its properties and characteristics were back then? And besides, it had already worked its way through a layer of joint compound – in just one night! No sense in taking the chance that it might bleed through this nearly-white grasscloth natural fiber wallpaper.

The Gardz penetrating primer / sealer (not pictured) I planned to use on the wall would be fine to hang wallpaper on, but could not guarantee that that brown stain would not work its way through the primer and through the wallpaper.

I applied the Gardz, because it’s a great penetrating substance that seals new smoothing compound, and also provides a good surface for hanging wallpaper on. Once that was dry, I followed that with a coat of KILZ Original, an excellent oil-base stain-blocker. But wallpaper paste will not stick to the new KILZ formula (required in order to comply with current EPA requirements.

A little 3″ width around the lower center of the room with wallpaper not sticking tightly to it probably would not be problematic. But you never know, and I didn’t want a “hula hoop” of delaminated wallpaper circling the room. So once the KILZ was dry, I followed up with a coat of a wallpaper-specific primer, Romans Ultra Prime Pro 977.

Now the room is ready for wallpaper, without fear of a band of tan bleeding through the new surface.