Z-Brick Removal #4
This week’s installment of Kitchen Renovation Nightmares concludes my account of removing the Z-Brick from the walls of our kitchen and laundry. See the first installment of Kitchen Renovation Nightmares for the beginning of the discussion.
The second installment described the test I decided to try and the preparation of the wall.
The third installment detailed the initial skim coating test process that I tried and the results. My test area looked fairly smooth and was much better than having the Z-Brick.
This week I will explain refinements to the skim coating process that I learned subsequent to my initial test.
My test effort left me convinced that I could remove all of the Z-Brick and get a reasonable finish. I hoped that the walls would look pretty good once they were painted. I was not sure whether we would need to apply a light orange peel texture to hide any unevenness. In the end we did not need to add any texture.
The first refinement involved a better technique when applying and scraping off the joint compound (also known as “mud”). I watched some additional videos, and I paid attention to some professionals skim coating the ceiling of our kitchen.
I discovered that a stiff taping knife was the best for me when applying and scraping off the mud. The knives come in various sizes with 10 to 12 inches most commonly used for skim coating. However, I found that I was best able to handle a 6-inch knife for the areas that I was skim coating.
Rather than a bucket or a paint tray, I purchased a stainless steel mud pan. This is a 3.5-inch deep rectangular pan that holds the mud you mix, apply, and scrape off.
Now, rather than using the pre-mixed joint compound, I mixed just the amount of powder that I needed in my pan. Again, I wanted a creamy texture (think sour cream). Make sure the pan is completely clean of any old mud or debris, or it will corrupt the mud you mix.
You can get faster and slower drying times for the mud, so be sure to only mix up what you can use before it starts to harden. I mostly used 20-minute mud, but be careful, because 20 minutes goes by very quickly.
Once I had the mud mixed in my pan, I used my knife to slather a generous amount onto part of the section of wall I was working on. I worked in approximately 4’ x 8’ sections. This meant that I started at the top of the wall and applied the mud to a couple of feet of wall. Next, I scraped the knife clean on my pan. I also kept a damp rag handy to wipe off the knife and any splatters.
Using the clean knife, I scraped down the wall removing most of the mud that I had just applied. I scraped off the material from my knife into the pan as I went. This leaves a thin coat on the wall and fills in the depressions. I kept applying and scraping off the mud until I finished the section.
After the mud dried, I sanded the section smooth, and I re-coated the section as I deemed necessary. Two to three coats left the wall smooth.
The final trick to getting a very smooth finish is to use taping and topping compound. This material comes in a plastic bag inside a box. It looks and feels like sticky bread dough, so you have to thin it to that creamy consistency. You don’t need much. It leaves a very smooth finish that you sand with fine or very fine sandpaper.
After the wall is dry you need to prime it with a primer/sealant meant for drywall. This will seal the wall and leave it ready for final painting.
As an illustration, here is one kitchen wall after I had removed the Z-Brick and prepared it for skim coating.
Here is the same area after skim coating two coats and sanding.
And here is the wall after applying the taping and topping compound, priming, painting and finishing the surrounding areas.
Good luck, and let me know if you try this.