Blistering plaster and leaks

[willyd]

Hi,

The plaster of the top step of my pool is blistering and possibly causing the pool leak (can't really find the leak until this problem is resolved). What is the best method of repairing this? Where can I buy the supplies to replaster this step? From reading the forums, I believe I need to do the following:
1. remove blisters, chipped plaster, etc.
2. sand smooth, feathering edges
3. apply a "bondcoat"
a. don't know where to buy
b. can I use an epoxy based product, can someone suggest a product
4. trowel on plaster coat
a. what is the best product to use
b. where can I buy the product

BTW, this is a 18'x35' "white" inground gunite pool.



Thank you,



WD.

[rlanthony@excite.com]

WD,
I don't know if you have fixed your problem yet but I had the same problem a couple of years ago. The blisters are from either rust from water reaching the rebar beneath the plaster or not a good bond with the bond coat beneath. I fixed mine by using a circular saw with a masonary blade to cut just the plaster, about 1/2 inch. I cut a square hole then used an air chisel to chip out the plaster down to the concrete. A regular cold chisel and hammer will do. remember chisel only the plaster, not the concrete. I had to cut out some shallow rebar that was rusting with a metal blade on the saw. Clean the area very well after chiseling for a good bond. If it's wet it doesn't matter. I then mixed new plaster and filled the hole. The plaster is the water barrier from leaking, not the concrete beneath. You have to work the plaster when it starts to set a little. This may take an hour or two. Use a piece of heavy plastic to work the plaster, such as a coffee can plastic lid, cut with a smooth edge. You have to work the plaster until it sets pretty well. You will be able to see the repair, but I don't think there is a way not to. As the plaster sets somewhat, but not all the way firm, refill with water. Ther plaster will set and cure under water. No stepping on the plaster for a least 24 hours.

Let me know
You may want to e-mail me with questions. I don't ckeck this site much. Just put "pool repair" in the subject line.
rlanthony@excite.com
Rick