Q: My company has done plaster repair work for many years. After repairing water-damaged walls or ceilings, we occasionally get called back to "fix" an unsuccessful repair. Our second repair attempt involves digging out a very bumpy, chalky substance, and more often than not, we have to repeat this process a number of times until the patch finally takes hold. What causes this reaction on some water damage jobs and not others? What is the most efficient way to deal with this problem?
Q: In our remodeling business, we often demolish plaster and drywall in old homes, and find that the dust and fine abrasives work through just about everything we put down on the floor. What method do you recommend for protecting floors? Also, do you have any recommendations for a shop vac that works for drywall dust?