Icesailor
I'm a master plumber in business for 40+ years. I am in the process of selling the house I now live in, and the prospective buyers hired a "home inspector." The only thing he found was a spot of slightly peeling paint in a second-floor bedroom ceiling, so he poked a hole through it. Now there is a hole in what was an absolutely flat, Imperial skim-coat plaster ceiling.
I fixed the leaking roof flange in the main plumbing vent that caused the leak; the problem is the hole. What is the best way to patch it without it showing badly that it was patched? (I have access from above.) A 12" x 16" patch will do. Should I sand and feather the skim coat on the existing board so I can use mesh tape? I'm trying to make it as unnoticeable as possible. I'll have to paint the whole ceiling and the wall next to it so it matches. Any thoughts or suggestions are appreciated.
calvert, Dallas, PA.
You can just clean up the edges of the hole and glue a piece of drywall or plywood in place above the hole followed by an application of "hot mud," such as Durabond 20 or Durabond 45. You can then put a light top coat of spackling paste over that. You can lightly sand to flush up the new surface to the original. You don't really need tape if you use the hot mud.
If you really have to make a patch 12" x 16" you could glue and screw a piece of drywall in place and leave a 1/4" gap around the patch and fill it with hot mud, as above, skim, and sand. Don't use mesh tape.
Icesailor
Where the water leaked, it caused the board to "cup" down and I can see that the board has pulled away from the strapping. That's why the 12" x 16" patch I am thinking of doing. Durabond is a consideration.
I've cut a lot of holes in veneer plaster in my time. I never cut out willy-nilly but always on solid backing. I leave it for the patchers to do their job right. That said, I've never seen a patch that didn't look like a patch, especially in a ceiling. I was afraid of the joint cracking without mesh tape. Cutting the old wallboard usually leaves a raised edge which ends up higher than the new board. I wanted to grind it off and lower it for mesh tape.
It has become a project, not of my doing. This "spot" was next to a closet that has a ceiling opening. If the guy had looked in there first, before blowing a hole in the ceiling, I wouldn't be in this mess. The board, although it had been wetted, didn't have any holes in it. And the leak was because the rubber boot on the flashing had failed.
I just want to do it right. It's a personal character defect of mine. The plumbing and heating I do for my customers is meant to last. So is what I do for myself.
Maybe I shouldn't worry about it. In another month or so, I won't live here.
calvert
Icesailor, if the original blueboard is 1/2" and you have a veneer finish over it, then the new piece of drywall will still allow a thickness of Durabond and spackling paste to be applied over it and blend flush to the edge of the original material.
You didn't say if the finish is a one-coat or a base-and-finish plaster system. If you decide to sand or grind into the finish coat to provide for taping, be prepared for a bit of a task, as the veneer plaster "one coat" material is quite hard, and the base coat in a two-coat system is even harder.
As I stated in my earlier post, if you allow a sizable enough gap between the new blueboard/drywall patch and the original material, something in the 1/4" to 3/8" range, pack it with hot mud, and then skim the patch with hot mud followed by the spackling paste, you will then basically be able to lightly sand the surface to be in plane with the original plaster surface.
Then wet paper tape and apply it over the joint after sanding a slight bevel into the edge of your original finish material. Wetting the tape will allow you to slick it down to a very tight joint with the assurance that the paper will not be drawing out moisture and creating a weaker bond to the compound or spackling paste. By the way, I am saying "spackling paste" and that is what I mean, not pre-mixed joint compound. Paste is a finer particle size than joint compound and more closely approximates the consistency of true lime putty finish plaster.
