Affixing 3/8" Blueboard and Plaster to an Existing Horsehair Plaster Ceiling

[gobofraggle]

I would like to repair a hundred-year-old horsehair plaster ceiling by attaching new 3/8" blueboard and then skim coating over it. The old ceiling has some rather large holes in it (too large to repair), so I'd just like to go over it with new materials.

Here's the catch: There are no wood studs. The building was converted to condos from an old hotel (circa 1895), and the plaster ceiling is attached to extruded steel lath (in a diamond pattern, with holes of about a 1/2") that is attached via steel rods to the steel and concrete beams that support the building. So, there's no wood to screw into.

The plaster will hold a screw, but it's not going into a stud. So here's my idea: Apply construction adhesive (Liquid Nails) to the back of each blueboard sheet. Then screw it up on the ceiling. The glue alone probably wouldn't hold it, and I wouldn't want to rely on the nails alone, but TOGETHER, I think it will be safe.

So my questions are:

---Is this the best way to achieve this?

---Are there any alternatives, such as using very wide screws that will grab the steel lath, that you might suggest?

Overall, I'd like to avoid framing, since it will increase the cost exponentially.

Thanks!

[BobK207]

OP-

This looks a lot like another thread.

How sound is the exisitng ceiling lath? How many sq ft? Do you own the condo? Are you going to keep the place?

What's the goal? How good a result are you after?

btw that would be "expanded metal lath"

Even large holes can be repaired.

1. Weave in new lath with hog rings & wire......repair exiting ceiling

Blueboard dds weight but not a lot of strength.

1. Re-lath entire ceiling with a new layer of expanded metal lath screwed to exisitng ceiling

1. Demo ceilign & start over

Hard to make a recommendation from afar.......

cheers Bob

[benick]

IF the existing metal lath is OK I would knock off ALL loose plaster,scrape off any peeling paint and the cut wire mesh to fit the hole with tin snips and screw it to the metal lath with self tapping 1/4 inch pan head screws(we call them peanuts..LOL).Apply bonding agent to the WHOLE ceiling with a paint roller.New Plaster WILL NOT bond to the OLD plaster without it.Patch holes with Base Coat Plaster , then plaster the whole ceiling with Finish Coat Plaster.

If the metal lath ISN'T structurally sound then it needs to be taken down and replaced and you never know what you will be getting into when you open that can of worms. So if you go that route be prepared for a BIG bill ,a big mess and other unforseen costs along the way... Hope this helps...

[EXT]

It is messy but you may want to install sheet metal furring strips and wire them up to the metal lath, trying to get as close to the steel rods as you can. It will take a lot of wiring, and each piece of wire will need a hole on each side of the metal furring strip to get the wire over and back down. Be sure to tie the wires off well so they don't pull loose and use lots.