Posts Tagged ‘joint compound’

Tape Test for Unstable Walls

September 21, 2022

There can be reasons for unstable walls, mostly cheap or poor quality paint, dust, someone applied paint over dust, improper prep, incompatible layers inside the wall built up over years (oil based paint, latex paint, dust, gloss paint, joint compound, etc.).

These can cause problems with wallpaper, mostly with the layers delaminating (coming apart), which causes the wallpaper seams to come away from the wall. Sometimes sheets of wallpaper simply fall off the wall.

This isn’t so much a problem with paint, because it just sits on the surface. But wallpaper shrinks when the paste dries, or expands and contracts with humidity, and can put tension on the seams

Before wallpaper goes up, one way to test for such unstable surfaces is the tape test . Use a razor blade to cut an “X” into the wall, scoring through the paint and maybe into a few layers beneath. Place a strip of blue painters tape over the cut. Pull the tape off the wall.

If paint comes away from the wall along with the tape, or if layers inside the wall come apart, you know you have to do a lot of specialized prep to stabilize the wall before hanging / installing the wallpaper.

This example is an interesting twist. The homeowner used a piece of tape to hold up a wallpaper sample. Then used an ink pen to write notes on it. When removed, the tape took the paint off – in the shape of the writing!

Smoothing Over A Mess

August 3, 2022
This kind homeowner had the sink / vanity in this powder room removed. This makes it a LOT easier and faster for me to to get the wallpaper up, and with less stress on the paper and fewer relief cuts .
Removing a sink that’s attached to the wall often damages the surface. Here you can see how the workman used spackle compound to cover the torn drywall and other damage.

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Close-up. This isn’t a very smooth surface, and the wallpaper will have a hard time grabbing ahold and adhering. It’s also way too porous and crumbly to support wallpaper.
In the top photo, you see where I have applied smoothing compound on the upper portion of the wall. I’m working my way down.
Once it’s dry, I will sand and prime it, and it will be nice and smooth.
Here’s a shot of the fresh smoothing compound, before sanding.
Some people use a drywall taping knife or a broad knife to apply the plaster-like substance. I prefer the trowel you see in the photo, because it gives me more control and precision.
The 2″ flexible putty knife is for getting into smaller areas. The 3″ stiff ” Hyde ” putty knife is for knocking off high points or bumps on the wall before applying the smoothing compound.
This process is called skim-floating or skim-coating .
I like to use the Plus 3 lightweight joint compound made by Sheetrock . We just refer to it as mud . Find it in the drywall aisle.
The Plus 3 spreads on easily enough, sands easily , and the dust falls to the floor where it can be vacuumed up easily – as opposed to getting air-borne and drifting all over the place.
This box, which is approximately one cubic foot , weights 32 pounds . Ugh. Try carrying that across a parking lot and then up to the third floor of a townhome!
I like to transfer the material to a 5-gallon bucket. This is what it looks like in the bottom of the bucket.
Easy to scoop out. When I’m finished, I use a wet hand to smooth down the surface, wipe residue off the sides of the bucket, then place a thick sheet of plastic over the surface to keep air from drying it out. Then, of course, I put the lid onto the bucket.

Finished Wall Re-Do – See Previous Post

July 26, 2022
Here’s the wall after I stripped, sealed, skim-floated, sanded, and primed it.
Finished. The birds in the pattern balanced nicely with between the ceiling line and the wainscoting.
I had more success with this install than the previous guy, due to proper prep, and also the material used this time was the user-friendly non-woven , rather than the old fashioned pulp type wallpaper the other guy had to wrestle with.
Strawberry Thief is a very popular pattern right now, and comes in many colorways. Do a Search here to see my other installations of this design.
There were some issues at the top of the wainscoting where the painters had used tape to mask off areas, long with caulk, an it left a rather large (1/8″) unpainted area between the wood molding and the wall. I filled this in with joint compound and primed it, and wallpaper would have adhered just fine. But that would have left a white gap between the wallpaper and the green molding.
I rummaged in my truck for the best matching paint I could come up with, and painted over the white edge. This would have left a bit of a thin brown line between the wallpaper and the green molding. It would have looked OK, but I had an idea to get rid of the gap altogether.
If I had used my regular thin straightedge (the red one), it would have let me trim the bottom edge of the wallpaper nice and close to the wall. But that would have left the aforementioned brown line showing.
So I used the metal plate you see at the upper right of the photo as a trim guide. It’s thicker than my red straightedge, and so gives a fat cut that leaves more wallpaper and less of that brown line.
In fact, the left edge, as you can see, is rolled, and that creates an even thicker edge to trim against, leaving even more wallpaper at the bottom of the cut. See the photo just above, to see how the wallpaper now completely covers the brown line.
These metal plates have a lot of other uses. They are made and sold by a fellow member of the Wallcovering Installers Association . She makes a lot of other cool tools, too. If you are interested, send me an email. wallpaperlady@att.net
The wallpaper design is by William Morris , a famed artist of the Arts & Crafts / Art Nouveau periods . The brand is Morris & Co.
This label is EXACTLY the same as the pulp material the original installer worked with – save for that one word non-woven . Be sure you get the non-woven version, which is also called paste the wall .
The home is in the Heights neighborhood of Houston .

Wall Prep Ahead of Wall Re-Do

July 20, 2022
This wallpaper in a Houston Heights townhome’s breakfast area was hung by “the contractor’s guy ” and he ran into some problems. First, I suspect the wall had not been adequately coated with a primer designed for use under wallpaper . This may be a large part of why the paper has come loose from the wall in places, and shrunk and gaps at the seams.
The wallpaper is an old-fashioned British pulp material , which is quite different from the non-woven material that this company usually prints on. If the installer was not familiar with hanging a pulp, yes, he can have a tough time of it.
There are other issues that the homeowner is unhappy with, such as tears, slices, patches, and, of course, these un-stuck seams. I’ve posted more pics previously, if you can Search to find them.
My task is to get the paper off and then prep the wall for hanging new material.
Most of the paper pulled off the wall easily. But there were areas where the guy had used a stronger adhesive to try to hold the edges down. Those would not come off the wall without causing damage to the wall. So I pulled off the top, inked layer and left the paper backing on the wall.
This stuff is porous and will bubble when coated with a water-borne primer , and with wallpaper wet with paste.
So I sealed these areas – I sealed the entire wall, in fact – with Gardz (by Zinsser ). This stuff is pretty incredible. It’s a thin, watery primer / sealer that soaks into the surface and binds loose components together, then dries hard and solid .
Latex paints and other water-based products (usually) won’t penetrate it, so won’t cause the underlying material to re-wet, expand , and bubble .
Just a note … due to pandemic and other supply chain related shortages , Gardz has become difficult to find. This can was about 1/4 full and I had it sitting behind my trash can, intending for weeks to toss it out. Now I’m glad that I procrastinated!
Once the Gardz sealer was dry, I skim-floated over it with joint compound , a.k.a. ” mud .” In most areas of the wall, my skim coat was as thin as possible, but I did have to make it much thicker over the areas with the paper backing stuck to the wall.
I set up three fans , and also used my heat gun , to get the smoothing compound to dry. I like the Plus 3 version made by the Sheetrock company. It sands easily and doesn’t make too much air-borne dust.
It took a couple of hours to dry. Then I sanded it smooth , vacuumed up the dust with my Shop Vac , used a damp sponge to get residual dust off the wall , and then let the wall dry once again.
Finally I applied a coat of my favorite wallpaper primer, Pro 977 Ultra Prime by Roman. I used a paint roller to roll it on to the main areas, and an angled trim brush to cut in around the ceiling and moldings.
Here is the wall all smoothed and primed .
Originally I had planned to strip , prep , and hang this half-wall all in one day. But ended up the prep took more time than I anticipated (about 8 hours ) , so we’ll let the primer dry overnight and save the wallpaper installation for another day.
The wallpaper pattern is called Strawberry Thief and is by the famous William Morris designer from the very early 1900’s . I’m sure seeing a surge in interest in his patterns, particularly this one. Do a Search to see other jobs I’ve done with it.

For All You Dreamers Who Think That Liner Will Smooth Texture Walls … NOT!

June 23, 2022
Some people have spent too much time on YouTube or DIY websites. There is a misconception that liner paper will smooth out textured walls.
Nope, sorry, it ain’t happenin.’
The special type of paper called liner is used under some wallpaper s, and serves certain functions. Smoothing walls is not one of them.
If you’re planning to hang wallpaper over textured walls, liner paper cannot be used as a replacement for skim-floating , sanding , priming , and properly prepping the walls .
As you can see in the photo, liner paper shrinks as the paste dries, and pulls tight against the wall. This means that little imperfections will show through.
In the photo above, a towel bar had been removed, and the support bracket had been stuck / recessed into the wall paint , so the indentation and ridges from the bracket were still evident on the wall.
Covering them with a wallpaper liner helped mitigate them a bit … but, as you can see, the raised outline of the mounting bracket is still visible.
The issue is that this raised area, covered with liner or not, will still ” telegraph ” through the new wallpaper, creating a noticeable and unpleasing look.
To properly smooth a textured wall before hanging wallpaper, the surface must be skim-floated with joint compound (also referred to as mud ), sanded smooth, wiped free of dust, and then primed. Now the wall should be smooth enough to provide a good surface for the new wallpaper.

White Grout Can Be Distracting

June 7, 2022
The mortar along the top of this marble tile baseboard was light colored, and I didn’t think it would look good between the black tile and the mostly-dark wallpaper.
In addition, I hate trimming wallpaper against grout, because the gritty texture makes it hard to get a neat cut. And that sandy grout sure eats up my razor blades!
So I applied a thin layer of joint compound over the grout, sanded it smooth, and then sealed with a penetrating primer called Gardz. This gave me a softer surface to trim against. But I was still left with a white edge. That’s what you see in the top photo.
So next I used an angled artist’s brush and some black craft paint from Texas Art Supply hobby store to change the white line to black.
Here’s what it looks like finished.

Patching a Hole Around a Pipe

April 27, 2022
You’re looking at a water supply line underneath a pedestal sink in a powder room.
This hole is a little wide, and offers the wallpaper nothing to adhere to. In addition, there is no escutcheon (decorative plate) to hide the hole.
I took some special paper and cut a ” collar ” to fit around the pipe and also cover the hole.
I dipped the “collar” into Gardz . This is cool stuff. It soaks in to porous surfaces, adheres to surfaces, and dries hard.
Here is the patch in place. Once it’s dry, I’ll skim-float with joint compound (” mud “) and then sand smooth.
The finished product will be a smooth, intact surface for the wallpaper to adhere to, with only a tiny gap around the plumbing.

Stuff Doesn’t Wanna Stick To Slick

March 23, 2022
Tomorrow this breakfast area wall will get wallpaper. Today is prep day.
The wall has a very heavy texture, plus some issues with previous patches in areas, probably due to drywall cracks. I need to skim-float over all this to smooth the surface.
In addition, the current paint is quite glossy – and this can present a problem for the smoothing compound to adhere to it properly.
So I want to prime over this gloss paint before I skim-coat the walls. The primer has to both stick to the gloss paint and provide a base that the smoothing compound will adhere to.
Another issue is that I won’t be using this every day, so keeping it shaken up and useable was a consideration. I looked high and low for an appropriate primer. Finally I snapped that the Roman Ultra Prime Pro 977 that I use under my wallpaper jobs checks off all the boxes … It sticks to just about anything, and it dries nice and flat / matt so any topcoat (wallpaper or smoothing compound) can grab ahold and stick, I have it in my van all the time, and I use it frequently enough that it’s always mixed up and ready to use. To top it all off, it dries in less than an hour. VoilĂ !
This stuff can be tricky to find. Sherwin-Williams used to stock it for me, but became unreliable. Now Murphy Brothers on Bissonnet (Houston) gets it just for me.
Besides dropcloths on the floor, here I’ve tacked strips of thin paper dropcloth material along the wainscoting (I also do this along baseboards) to keep any drops or roller splatters from marring the homeowners’ floor and moldings.
Here it is applied. Since my goal is to cover and eliminate the glossy paint, and then provide a base for the smoothing compound, this coat doesn’t need to be opaque or cover the wall evenly.
Tomorrow we’ll see how the wallpaper turns out!
Fast-forward … I’ve floated the wall and sanded it smooth. Compare the smoothness to the “before” picture at the top.

Smoothing a Textured Wall, Continued

March 3, 2022
Continuing from yesterday’s post … The smoothing compound has dried and I’m ready to sand it smooth. This photo gives an idea of what needs to be sanded down. Some areas, such as around electrical outlets, are more irregular and have more raised areas to be sanded down.
Before I get to the sanding, a 3″ stiff putty knife comes in handy for scraping down high areas.
For decades, contractors wrapped sandpaper around a wooden block and used that to sand walls. Then, about 25 years ago, some genius invented these sanding sponges. They’re soft, flexible, easy-to-hold blocks covered with sanding fibers of various grits. They have angles that aid getting into various corners. I find that the edges can be a bit “pointy” and can gouge into the surface, so I often use a scissors to cut off the corners, as you see in all but the one on the far left.
Held against the actual wall.
Don’t forget a dust mask, to prevent inhaling the fine particles. And, yes, this is an N-95 … The same mask that protects us from ingesting the COVID 19 virus also protects the lungs of us home improvement contractors.
Manufacturers have done a good job of creating joint compound whose dust settles to the floor, rather than going air-borne and sifting all around the room. Still, it’s best to take measures to keep dust out of the rest of the home. Here I’ve hung a sheet of painter’s plastic across the wall, to contain sanding dust.
Once I’m done sanding, I’ll use my Shop Vac to clean up the mess, removing dust from both the floor and the walls.
It’s crucial that all dust be removed from the wall. If not, it’s like flouring a cake pan – the wallpaper (or paint) will kinda stick – but not really stick. Vacuuming the wall will not remove all dust. The only way to remove all residual dust is to wipe it off the wall with a damp sponge.
Look at how much dust has accumulated on the sponge after only a few swipes.
The sponge needs to be rinsed clean frequently. Once I’m done, I’ll dump this bucket of dusty water down the toilet (not the sink).
Swipes from the damp sponge will leave wet marks on the wall. These need to dry before moving to the priming step, so as not to trap moisture within the wall surface.
Here I’m rolling on my favorite wallpaper primer, Roman Pro 977 Ultra Prime. I have my paint store guys add just a bit of blue tint, to help me see where I’ve rolled it on. The short angled brush is for cutting the paint in around corners and edges.
I’ve tacked strips of dropcloth along the top of the baseboards, to prevent splatters.
Finished wall, nice and smooth, primed, and ready for wallpaper.

Starting to Smooth a Textured Wall

March 2, 2022
This is a typical wall texture provided by many builders of new tract homes in the suburbs of Houston.
Wallpaper doesn’t look good hung over this texture, because the bumps will show through. And the high-and-low ridges and dips interfere with good adhesion to the wall. So this accent wall will need to be skim-floated to smooth it before the wallpaper can go up.
In addition, this wall started out with a semi-gloss paint. I worry about my materials being able to stick to a glossy surface.
So, before applying the smoothing compound, I am priming the wall with something that will stick to the gloss paint, as well as provide a matt finish for the smoothing compound to adhere to.
I’ve discovered that my favorite wallpaper primer also works great for this purpose. It sticks to just about anything, and dries almost dead-flat. I like Roman Pro 977 Ultra Prime.
I use a trowel (top) to spread on the smoothing compound. The 3″ stiff putty knife is used to knock off big-ish chunks on the wall, or bits of grit. I use the 1 1/2″ flexible putty knife to apply the smoothing compound in tight spots like around electrical outlets or between a door molding and a wall corner.
The smoothing compound I use is drywall joint compound, and I like the Sheetrock brand Plus 3 version. Search hear (upper right) to see previous posts with photos of this material.
Bottom of photo – trowel sticking to the wall shows you just how tacky this stuff is. Above that are blobs of the smoothing compound waiting to be spread around, and a little bit on the left initially smoothed onto the wall. At the top of the wall you see a section that I have already covered with the smoothing compound. This will dry overnight, and I will sand it smooth tomorrow.
Sometimes I can float a wall, get it to dry, sand it smooth, prime, and hang the paper all in one day. But this texture is so heavy that more time is required for it to dry, so it will need an overnight sit. Some fans, plus the home’s heat and/or air conditioning help to pull moisture out of the smoothing compound and hasten dry time.