Portland Plaster?

Eric K

I am in the middle of doing a job that requires that 2 2'x2' patches be made in the ceiling. They are in the middle of the room approx. 25'x12'. House was built in 1954. We cut out the ceiling and found it to be 1 1/4" thick with wire mesh throughout. Also what we found was 3/8" copper line running through it (between plaster and joists) from the boiler. The plaster has about a 1" base of almost concrete/mortar looking material and about 1/4" of finish plaster.

What is going to be my best route on patching? Will regular drywall w/ hot mud work?

Or do I need to use a blue board with plaster? and if so what are the steps to doing it that way.

I am expirenced with regular board and hot mud but never ran into this type of base material. Thanks for the help.

Tscarborough

You can patch it with anything that will look like the rest. For historically accurate patching, it is probably cement/lime base coat and gypsum plaster finish.

Eric K

Thanks,
Just used drywall and 45 today on it. Turned out good.

Frankawitz

Erik
It sound like the 3/8 copper is for heating, using the board instead of ribbed wire lath may cause the ceiling to crack around where you matched in your ceilings repairs. so if you get a call back later on you'll know why, you could have used metal lath with your hot mud this way the heat tranfer would have been evenly spread, just my two cents.