Posts Tagged ‘humidity’

Humidity Damage to Vinyl Wallpaper

June 15, 2021

As I like to say, Humidity Is The Great Enemy Of Wallpaper.

This small bathroom with no A/C vent has more problems with moisture than most, as evidenced by the stains and flaking paint on the ceiling.

But let’s focus on the wallpaper. Back some decades, just about all you could find were these pre-pasted paper-backed solid vinyl papers. I have never been fond of them. https://wallpaperlady.wordpress.com/stay-away-from-pre-pasted-paper-backed-solid-vinyl-wallpapers/

the paper backing seems to absorb humidity through the seams. As it sucks up moisture, the paper expands, and that causes the paper to push away from the wall, creating the curled seams you see in the photo. It advances past that, to where the paper backing actually delaminates from the vinyl coating and from the wall. The surfaces come apart, and cannot be “glued down.”

A small part of this problem could have to do with improper surface prep, such as a good wallpaper-specific primer. But the brunt of the issue lies with too much humidity. An air duct in the room would help bring in fresh, dry, air-conditioned or heated air. And keeping the door open would have given humidity a way to exit.

But best of all would have been to avoid this low-end plastic / paper combination wall covering in the first place. A paper wallpaper, or one of the newer non-woven (synthetic fiber) materials would resist humidity much better.

Crumbly / Unstable Wall Issues

June 2, 2021
Starting to strip wallpaper. You see the top, inked layer, the tan backing layer, and the white skim-floated wall beneath.
Wall surfaces delaminating at seams
Gardz, a penetrating sealer that binds surfaces together and dries hard.
My first idea was to just Gardz the lifted areas. The sealer is newly applied and still wet in this photo.
Gardz’ing the whole wall created a more stable surface. This doesn’t look much different from the photo above. But in actuality, the the Gardz has sealed and “locked down” the surface, as well as soaked into the material and sealed the inner layers as well.
Applying a skim-coat to even out the surface levels.
Once this skim-coat is dry, it will be sanded smooth.

The installer of the original paper did a good job of skim-floating the wall and creating a smooth surface. But he didn’t apply a sealer or primer. Thus, when I used water to strip off the old wallpaper, the moisture soaked into his skim-coat (drywall joint compound, a plaster-like substance, which we also refer to as “mud”). Some of the skim-coat came away from the wall,,, particularly in areas of stress, such as where the wallpaper seams had lain.

In fact, long (years) before I began stripping the wallpaper, many of the seams had started to pull away from the wall, taking inner layers of the wall along with them. This is because wallpaper shrinks as it dries, and that creates tension on the wall. If the wall surface is unstable, these layers can delaminate (come apart), and the result is an open seam with chunks of wall material stuck to it.

This can also happen over time, as temperature and humidity changes can cause the wallpaper and / or wall surface to absorb and then let go of moisture. All this puts stress on those wallpaper seams and on the layers inside the wall.

Besides these seam areas that let go, I had one wall where the entire surface came apart in a mottled effect.

Another factor is that the original skim-coat had been applied over a glossy paint. It’s hard for anything to stick to gloss. The guy probably should have rolled on a “bonding primer” before applying his skim-coat.

Of course, all that increases the time and materials needed, and ups the cost to the homeowner.

Gardz is a wonderful product that is designed to soak into surfaces and “bind them together.” It dries hard and is pretty water-resistant. It was originally intended to “lock down” torn drywall. But workmen quickly discovered that it would fix a whole lot of other surfaces – such as my delaminating skim-coated walls.

At first I thought I would just Gardz (we use it as a noun and as a verb!) the areas that were lifting. Once it dried, I intended to skim-float over these areas, sand smooth, and then prime the entire room with my usual wallpaper primer – Roman Pro 977 Ultra Prime.

But I realized that, even after I wiped down the walls with a damp sponge, they were still covered with powder or grit. This was powder from the layer of skim-coat, as well as residue from wallpaper paste. Neither my primer not wallpaper will stick securely to powder.

So I decided to roll Gardz on to all the walls, ceiling to floor.

Fifth photo – I was really pleased with the way the Gardz soaked in and drew all those layers together. There was no more power on the surface, and the inner layers of the walls were all pulled together.

To even over these vacant areas, and to create a pristine new surface, I skim-floated over the entire wall surface – all walls, floor to ceiling. See last photo.

Once that is dry, tomorrow morning, I will sand everything smooth. Next I’ll apply my 977 primer.

Then walls will be stable, and the surface will be ready to take on the new wallpaper.

From Drab to Spa-Like

April 17, 2021
Before: Semi-gloss paint on bad texture job.
Virtually the same color, but texture and pattern add a warm and calm feel.
Before: Khaki paint
After: Serene, even Zen-like.
Close-up shows pattern that can be matched so seams are disguised, as well as string fibers that add texture and dimension.

Nearly a full 100 years old, this cottage in the Norhill neighborhood of the Houston Heights has seen many updates and treatments. The master bath suffered from various dubious renovation attempts, as well as the aftermath of acts of nature, such as shifting foundation, leaky windows, humidity. The whole room just had a sort of “last chance” look about it.

Most of the room’s ails could be solved by ripping everything out down to the studs and then starting anew. But on most budgets – that ain’t agonna happen!

So I skim-floated the walls and sanded smooth. Just having smooth walls free of the drab khaki paint color helped left the pervasive glum feeling.

The homeowner chose this faux grasscloth, which is a stringcloth product made by Walquest, in their EcoChic line. I like this because, being a man-made material, the pattern can be matched from strip to strip, so you do not notice the seams like you do with a natural fiber material like real grasscloth. Also, the vertical strings on the wallpaper give texture and dimension, which is a look that many homeowners are craving these days.

The label insert tells you straight off that this material is not washable (they say you can gently vacuum it occasionally). Yet it is still more resistant to stains than true grasscloth.

This wallpaper was purchased from Ted at the Shade & Drape Shop on Kirby at Richmond. (They have another location on Voss near San Felipe.)

Abstract Desert Mural for Baby Boy

April 4, 2021

Original textured wall skim-floated smooth, primed, and ready to hang.
Ready for the crib!
Close-up showing watercolor-like effect.
Rolling panels out on the floor, to check sequence, pattern match, measurements, layout, etc.

No teddy bears or rubber duckies for this baby-boy-to-be. His parents wanted a more earthy theme and color scheme, as well as a pattern that would grow with him.

This mural went on an accent wall. The crib will sit in front of it. The remaining three walls will be painted a light, earthy grey, which will make the whole room feel unified and snug.

It’s uncommon to have a door on an accent wall, and note that that 3′ wide door ate up a good chunk of the 12 1/2′ wide mural. I debated putting paper on that 1 3/4″ wide strip to the right of the door. But I’m glad I did, because it sets the door off and, most important, it provides visual continuity of the sand dunes and mesas moving across the wall.

That narrow piece took about 45 minutes. It felt really good that that was one of the first things the homeowners commented on when they came in to view the finished wall.

Anewall is the manufacturer. I really like most of their products. I had the homeowners avoid the vinyl version, in favor of this thin, pre-pasted option. You simply need to use water to activate the paste on the back, let book a few minutes, and it’s ready to hang. I always augment with a little extra paste, which this time I rolled onto the wall, especially under the seams. This will help prevent shrinking and gapping at the seams as the wallpaper dries.

The thin paper will hug the wall more tightly and be more resistant to humidity (curling seams) than the vinyl option. It’s not particularly soil-resistant, though, so the parents will have to make sure that little hands stay far away from the wall.

Although not printed on the label, I believe the actual manufacturer of this is York Wallcoverings, in their SureStrip line. I like just about everything this company makes.

The townhome is in the Rice Military area of close-in Houston.

Dark & Mysterious Witch & Watchman Wallpaper

January 29, 2021

This small powder room in the Rice University neighborhood of Houston was buried under at least four layers of old wallpaper. The homeowners intended to DIY new wallpaper. In the top photo, they have partially removed some of the layers. But not too far into the project they realized that the prep required was over their heads. Enter the Wallpaper Lady. 🙂

I won’t go into all the details of getting these walls into shape. But I will say that it took a day and a half, and I wasn’t completely satisfied with the end result. But sometimes you can’t surmount what was done over prior decades. I brought the wall to a good state for hanging the new paper.

And what a perfect choice they made! The original wallpaper was a beige faux-finish sort of design that was popular in the ’90’s. The couple wasn’t sure what they wanted, but, on our initial consultation, I showed them a sample of this that I had hung previously https://wallpaperlady.wordpress.com/2019/03/02/birds-on-black-wallpaper-by-witch-and-watchman/ , and they were instantly mesmerized. On the company’s website, they zeroed in on a slightly different pattern with equal drama.

The wallpaper is on a non-woven substrate, and can be hung via the paste-the-wall method. In bathrooms, with sinks and toilets and windows and other things to cut around, I find it better to paste the paper. It went up nicely, and should perform well for years, even being more resistant to splashes and stains than many papers. The non-woven substrate should resist curling at the seams caused by humidity – important, since this 100 year old home has no A/C vent in the powder room.

Why Are These Seams Pouching Up?

November 4, 2020

There are a couple of issues going on in this master bathroom, causing the wallpaper to curl at the seams and the layers to delaminate.

For starters, the previous installer did not bother to remove the original wallpaper, but hung on top of it. He did prime over the original wallpaper, which is good,,,, but that primer felt too slick to provide a good surface for the new wallpaper to stick to. I have a feeling it was not formulated for wallpaper.

Second, there has been a lot of steam and humidity in this room over about 15 years. This particular type of paper does allow moisture to find its way into the seams, causing curling and delaminating.

These pre-pasted, paper-backed, solid vinyl wallpapers are among my very least favorites.

Read more about this material by clicking the link below.

https://wallpaperlady.wordpress.com/stay-away-from-pre-pasted-paper-backed-solid-vinyl-wallpapers/

RePaste and Disguise Split Wallpaper Seams

October 10, 2020


Several seams in this bathroom, as well as some whole sections of wallpaper, had come away from the wall.

Most likely, this was due to a combination of things … Number 1, extreme humidity from teenaged son taking showers with no ventilation and over several years. Number 2, possible improper wall prep before the wallpaper went up. Number 3, Unstable surface, which allowed layers inside the wall to delaminate and separate from each other.

Whatever the culprit, I had success in using wallpaper paste to re-adhere most of the loose areas back to the wall. We were still left with visible gaps at some of the seams, where the wallpaper had shrunk.

I used water-based craft paint to color these areas. I didn’t use the brushes … I just daubed my finger in the undiluted darker tan paint and swiped it over the gaps, pushing to be sure it reached to the wall. Then I wiped excess off the surface of the surrounding wallpaper with a damp rag.

I used water to dilute some of the blue and red paint, and then added that over the appropriate colored areas. I used the tiny brush to dot on bits of near-black paint, to correspond with the black printed areas on the wallpaper map.

From a distance, you could not see the touch-ups. Even better – you could not see the touch-ups even if very close.

Solid Vinyl Paper Pooching at Seams

May 15, 2020


Today I stripped off this paper. It was dark and dated. But also, it had started curling up a bit at the seams.

The homeowners said this started after Hurricane Harvey, when they were without power for two weeks, and the lack of air conditioning allowed humidity to permeate the house.

So here we have paper-backed, pre-pasted, solid-vinyl wallpaper doing what it does best – succumbing to humidity, by allowing moisture to wick in behind the seams, which causes the paper backing to swell, pushing the vinyl surface back in a curl. Sometimes, the paper backing actually delaminates (comes apart from) the vinyl layer.

My main reason why I encourage people to steer away from these materials. The price point is attractive, but the quality and longevity is not.

Interestingly as a side note, it looks like the previous installer did not pay attention to the pattern match. Well, no biggie. On this design, it is not very noticeable, and the homeowners have lived with it happily for 20 years or more.

Repair Needed – Stashed Wallpaper Not Usable

April 5, 2020


I’m about to do a repair to some wallpaper that was damaged flooding during Hurricane Harvey here in Houston. Unfortunately, the left over wallpaper from the original installation was also exposed to the water and humidity of the flood. There is a little bit of water stain and mildew on the back of the paper.

This rendered the paper unusable, because both water stains and mildew will work their way through wallpaper (and paint and other surfaces), and will eventually show up on the printed side.

Luckily, there was enough left over paper for me to discard this stained area and then use undamaged paper for the repair.

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.