As noted above, finished flooring needs to be covered; you absolutely will drip joint compound and while it is water soluble and not difficult to remove, you will probably drip a. It is preferable to mix lightly even if there is no separation; mixing changes the consistency somewhat and will make it easier to handle on a knife. One last time use the same procedure as you have already used twice and cover nails and screws. You drill an 8mm hole through board and slab and hammer them home. "Mushroom" fixings (not sure if there's a proper name for them) are metal wedge type fixings for attaching drywall/insulation slabs to masonry walls. The skim coat should be at least eighteen inches wide over both flat and butt joints, and at least a foot each way on the corners. The savings in time and effort are enormous if you don't have to correct and fix the previous days work! This is the last chance you will have to produce a perfect job, so make the best of it and check carefully for any imperfections in the block coat. As regards filling over the heads of fixings (I'm using "mushroom" head type wedge fixings because I'm fixing directly to cavity (cinder) blocks), when you fill holes, do you sand as much as possible of the filling compound when it dries, back down to the paper on the drywall and right up to the perimeter of the holes, or just feather the edges? The slabs I'm using have a foil moisture barrier at the back covered with corrugated paper for protection, plus a foil layer between the drywall and insulation (which I think is some form of expanded polyurethane). While I was the quality super at a plant making mud for 22 years, I left that occupation a decade ago and have no contact with anyone in the field. Good tips - thank you! of compound under feathered edge. If your remodeling projects involve old plaster walls with moderate to severe damage, bathrooms with new tub/shower installations, or jobs that need to be completed in a hurry, then you need some inside information about how to use setting-type joint compound. That being said, excessive sanding of the paper on the wallboard will scuff it, and that WILL be visible. I'll get it down eventually. If using paper tape, apply a thin layer of joint compound to the wall (see picture for how much) and gently press the tape into it using only enough pressure so that it stays on the wall without holding it. Large amounts of dust, sawdust, or other materials will result in a lumpy wall and difficult application of joint compound. All-purpose joint compound, commonly called mud, is the wet material that is used for drywalll installation to adhere paper joint tape, fill joints, and to top paper and mesh joint tapes, as well as for plastic and metal corner beads. Although it is possible to buy texturing compound, many drywall professionals use regular drywall joint compound… Do not store in direct sunlight and protect from extreme heat and cold. I've seen professionals use just two coats on a smooth wall, but only once, and they did not find that it worked well. However, like any dry powder mix, it is susceptible to dampness, clumping, etc. Modern houses however are built using a double wall of 4 inch thick concrete blocks with a 3 inch cavity in-between which is filled with insulating slabs. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/6\/6f\/Use-Joint-Compound-Step-1.jpg\/v4-460px-Use-Joint-Compound-Step-1.jpg","bigUrl":"\/images\/thumb\/6\/6f\/Use-Joint-Compound-Step-1.jpg\/aid1355450-v4-728px-Use-Joint-Compound-Step-1.jpg","smallWidth":460,"smallHeight":306,"bigWidth":728,"bigHeight":485,"licensing":"