SEVEN LAYERS OF SEPARATION Some days aren’t so great on the job. When things are rotten I like to consider other really awful jobs I could be doing. One time I was watching a documentary on chicken processing plants and found out that there is a job which entails grasping two young chicks at a time from a conveyor belt loaded with birds and pressing their sharp young beaks against a hot iron plate to dull the very tips of the beaks. That’s 40 hours a week….probably with opportunities for overtime. It is against this backdrop that I would like to discuss the decorating professional’s worst chore, i.e. wallpaper removal. You see? It isn’t so bad compared with full time chicken beak searing, don’t you think? Interest in wallpaper removal is always huge and the one thing that binds painters and paperhangers alike. Most sensible people dread it. In the old days---actually the ancient days now---wallpaper removal was a breeze requiring almost no thought. The hard plaster walls people had then were hard as cement and wallpaper was just that, paper pulp, so the material sucked up spray water faster than shrimp disappears from an all-you-can eat buffet. With rock hard lime plaster you never had to worry about too much spray water softening the surface like it does with modern paper-faced sheetrock walls or unsealed joint compound turning into modern art during removal. Everything is different now. It is rare indeed when you don’t have sheetrock walls and rarer still when the wall was primed properly thanks to all the DIY massacres over the years. Once again in passing I would like to point out the attributes of a good wallpaper primer as opposed to a good paint primer; i.e. any film coating which allows good paste adhesion, a film that doesn’t re-emulsify after the extended dry time of most wallpapers and one that provides a barrier to prevent wet paste from getting into the sheetrock paper facing. Sadly, there can still be problems even when a sheetrock wall has had good priming and these problems can pop up after “dry stripping” and the subsequent re-hanging. Dry stripping generally means no steamer or pump sprayer is required-- the material is mechanically yanked from the wall. If you can pull on a piece of old material and if comes off the wall in one piece, chances are good it is fabric-backed vinyl. Since this material type is getting rarer and rarer in residences you are likely to be in a commercial removal situation for this type of removal. There really isn’t too much to advise you about if it comes off easily, but if you have to tense your whole body pulling on a 54” wide sheet you might want to consider some of the potential problems of dry stripping removal outlined here.
I called that humongous U.S. drywall company (you know the one I mean) with some questions recently. After they found out I wasn’t a spam caller they were glad to spend time on the phone with me because, let’s face it, usually only shut-ins with lots of free time like to chat about gypsum board. I asked specifically what adhesive is used to bond the drywall paper facing to the gypsum sheet. My drywall techie told me that there really is no adhesive binding the paper to the gypsum. In the process of drywall manufacture they spray on seven layers of wet paper slurry and each layer “knits” with the one underneath it—but there are no adhesives per se. Every so often the paperhanger will dry strip the old material and rehang with a new one only to find that bubbles—sometimes frightening large bubbles—will rear their ugly head hours after the material is installed. Usually if the wall was cleaned and primed with a water based primer these bubbles will become apparent before the new material is installed. But in today’s world of “no prime” strippable adhesives it is often the case that the wall is sanded for loose paste and the hangers are off and running to install the new stuff. This “stealth bubbling” afterwards, completely out of blue, can be a shock. More often than not the removal technique was at fault. The person removing the old material grabbed a sheet and pulled it with gusto using the wrong “direction of force”, i.e. they pulled it out and toward them instead of the proper direction which is pulling downward towards the floor. By pulling towards yourself instead of downward, you easily stress one of those seven layers of drywall facing paper and separate it from another layer. Here’s something else: No matter how tempting a sheet looks with its curled up corners at the baseboard, don’t pull up on it. It is very difficult to maintain the proper angle of pull in this way and doing a few sheets like this will only kill your back anyway. Luck usually prevails in most situations and it is the topmost paper facing layer that gets lifted and separated. Most of the time this becomes immediately apparent to the installer. However, bad luck comes into play when the sixth layer or so becomes delaminated. In this case even topcoating the drywall with a water based primer before hanging may not make the delaminated section bubble up since five layers of facing on top are thick enough to prevent a quicker drying water based primer from getting though to expand the paper and show the bubbles. Only extended soaking time of several hours or overnight with a new pasted sheet of material allows for penetration of moisture followed by the sickening “sagging” and bubbling in sections. Disclaimer: I must admit here that this is all conjecture on my part about what is going on in the micro world of drywall….the fifth, sixth, and seventh layer of paper facing that is. I don’t get any government money to buy electron microscopes and sequester a stable of guys in lab coats to examine thousands of sheetrock samples. The federal millions have all been spent on studies to find out if men are different from women (they are slightly) and if elk can regain their libido if salsa music is pumped into the woods. The previous section on delamination was compiled simply by me staring into a bowl of water and thinking real hard about layers of paper slurry and force vectors of removal. However, it all makes sense to me so I’m sticking with it. And did I say that no pump sprayer would be required for today? OK, I lied. Actually a pump sprayer can be invaluable in a dry strip situation to prevent stealth bubbling like this—but not to remove material. You should be concerned when excessive force is required in dry stripping and may want to use the sprayer to mist the wall you have just removed from. Keep the sheetrock facing wet for an extended period to force paper expansion in order to discover those deep stealth bubbles before application of the new material. Also keep in mind again that stealth bubbling due to wall stress can occur even if the wall was perfectly primed. In fact, perfect priming will work against you because it will seal off the spray water from getting deep into the paper facing layers to indicate problems if you accidentally overstressed the drywall facing. Besides spray water you can use your ears as an indicator for stealth bubbling, too. How about this unusual tip from Eunice Bokstrom , a hip paperhanging chick from Canada: “Run your hand over the surface of the wall and listen for areas that are blown or delaminated - you can't see them, but you can ‘hear’ that there is a void.” We all know Canada is a very quiet country so this tip may have to be altered a bit for U.S. consumption. First you have to tell your guy with the nose ring and the paint spattered “Rage Against the Machine” T-Shirt to uncrank the Home Depot boom box and then listen to the wall. Here are a few other tips for dry stripping which come from Long Island’s own Lou Ligeri—the East Coast Dalai Lama of Wallpaper Removal. Lou, a longtime NGPP member, travels around the country giving lectures and lessons on wallpaper removal and we get these two great insights from the man:
In parting, let me share this unusual technique which may involve raiding your significant other’s baking supplies. An ordinary wooden rolling pin can be used. Pull enough old material off at the top to wrap around the rolling pin or even duct tape the top edge of material to the pin and then press the rolling pin firmly against the wall as you roll it down to the floor. This provides the right “shear angle” for the paste to break yet keeps constant pressure on all drywall paper layers to avoid any delamination. Next time, I hope to get into the “wet stripping” techniques. What? You were expecting some sort of cheap “Tuesday Night: Ladies’ Mud Wrestling” references? Hey, I got through “dry stripping” with barely a quip. |