Bare with me, this is a long one. 1927 Dutch colonial. A few years back I removed existing roof. Before re-roof we had a gully washer that pushed tarps in and soaked second floor. Now. I’m removing stained horsehair plaster from the ceilings. The beams in ceiling/attic floor are bowed towards center of room light fixtures, where the water came out. The bow isn’t slight or light, it’s probaly a 2″drop from the walls, at the fixture point. These ceilings are the crux of this remodel. I already know I’ll remove plaster from walls, re-wire and insulate, but it’s the ceilings that are killing me. Here are alternatives I have looked at;
a. Drop ceilings. The kind used in office buildings, etc.. Kinda ruled those out as I’m not real fond of that look.
b. Re-Plaster into the old lath, paint and ignore the bow.
c. Remove lath and old insulation from ceiling. Re-wire, insulate, blueboard, then plaster over blueboard.
d. Look into jacking joists back into place, sister some joists, insulate and drywall. I have never jacked or sistered so this would be new stuff to me.
e. Go to Breaktime and ask the pros. Here I am.
Thanks in advance for suggestions.
Todd
Replies
The joists do not need to be jacked, as they have not moved. The plaster has instead pulled away from the lath to which it used to be keyed. In other words, it's structural bond to its armature has been comprimised. It is going to continue to fall - until it falls off. Don't know how long that will take. I do know that it will continue to get worse. It can't EVER get better. Plaster is not elastic in the sense that you can get it to move back into its original form in its original condition.
The remedy is only to remove the plaster. Personally, I would then remove the wood lath as it no longer serves its original purpose and it cannot be certain that it is sound throughout. Whether you use drywall, blueboard, or wirelath and a 3 coat plaster system, to sheath the ceiling, is your call.
Most certainly there will be other existing conditions -insulation, electrical - you will need to address.
F
You could go period with a tin ceiling over existing lath, or a flatter option would be to shim strapping on 12" centers to nail to. I have done it with very nice results.
Hope this helps.. Rich.
I have had a lot of success on smaller jobs with the special washers and SS screws which will tie the plaster back into the studs - but only on smaller jobs. If it's a complete ceiling, tear it out and do the drywall/blueboard.
Quality repairs for your home.
AaronR Construction
Vancouver, Canada
Given straight joists and sound lath, I've had good success with using yellow woodworking glue applied from above to strengthen old ceiling plaster. Parts that were sagging away from the lath I pushed up using plywood and jacks from below. Plastic sheet over the plywood in case any glue drips thru.
If the joists really are sagging, it's probably not worth the effort to try to save the plaster. Better to scrape it down with a straight blade shovel, then pull the lath, and sister or replace the joists to current code. It's also a bunch easier to do your plumbing and electrical with the joists open, before you put up your new ceiling.
-- J.S.