Church pool RE-construction

[Sumo1]

I've made references to this church pool rebuild in other threads but will try to focus future discussion here. For background, see thread titled,Re: Filter sand, a gritty question. I don't know how to quote it here but the last posting in that thread gives a broad idea of this DIY project.
Question of the day; As we enlarge our pump house to incorporate new piping, we want to add floor level exhaust fans to clear the room of chlorine gases. Should we be concerned about rapid corrosion of the fans by the chlorine?
Hal

[MarkC]

Are you planning on running the fans 24hrs a day? If you are I would mount the ffans so that they blow fresh air into the building and have an open vent for it to exhaust somewhere on the other side of the room. That way the fan is seeing fresh air as opposed to using the fan to pull the chlorine contaminated air through the fan.

[Sumo1]

No, I don't think the fans would run 24/7. Probably just while someone was working in the pump room. We were thinking of using 90 minute timers to control them. It's just a cinder block walled room.
Hal

[Sumo1]

New question, same project... Subject: Plastering The last step before refilling the pool will be a replastering job. We're considering doing the sandblasting ourselves to save money. Any comments on that idea? How about it, Mr. Gutierrez? Also, there are a couple of large(12"-15" dia.) spots where the plaster is worn away, exposing the gunite. We figured to apply a thin coat of hydraulic cement to those areas, but one plaster company I talked to said it wasn't necessary, that their 3/16" final coat would be sufficient. Does that sound right or should we go ahead and make a hard, smooth surface below the plaster coat? Thanks
Hal

[Sumo1]

Well, I've met with a couple of plastering companies and have gotten answers to my questions in the previous post, so now we'll move on....
QUESTION OF THE DAY: In the 6' end of the pool there is a 'diving well', We've decided to fill it in because diving is no longer allowed. It's approximately 10'X12' and 3' deep. What would be the best material to use for fill?? We figured to fill and compact it to within a few inches of the rest of the pool floor and top it with shotcrete. Then when the pool is replastered, the floor would be smooth and the circulation problem presented by the diving well would be remedied. Thanks
Hal

[Poolsean]

I suggest making sure you prep the surface of the old cement before pouring the new material to fill in the deep end. Sand blasting and in some applications, chipping the surface, allows a better bond and removes all loost plaster/cement. Also, a bonding layer, such as Multicoat scratchkote, will help adhere the new surface to the old.

Will this new 3' end still be the deep end? If not, there should be some sort of drain at the deepest part of the pool for debris to settle and be sucked out by the pump. If not, I'd recommend that you go a little deeper than 3' so that is it the deep end, THEN don't forget to bring up the bottom main drain.

[Sumo1]

Poolsean, in your suggestion about filling the deep well(Sorry I'm such a dummy-don't know how to insert quote here ),are you thinking we would use a poured material like a cement product? I was thinking of something like a bed of gravel. This is precisely why I'm asking for advice.

The new 3' spot would still be the deep end and thus would have to be slightly lower to facilitate drainage. The hydrostatic valve will be brought up to the floor level, as will the main drain. The main drain will be "Teed" off to give us two main drains and bring us into code compliance.
Hal

[Poolsean]

It may be as easy as pouring cement, although that's a lot of cement. Perhaps gravel then cement over it, or compacting dirt then cement. I think in either case, you're better off going with the opinion of an expert structural engineer.
I would think that you'd want to grid rebar on the new floor and tie it into the existing pool rebar.
I wish I knew more on this.

[Sumo1]

Thanks, Sean. Maybe one of the PBs will chime in....
Hal

[GutierrezPlastering]

New question, same project... Subject: Plastering The last step before refilling the pool will be a replastering job. We're considering doing the sandblasting ourselves to save money. Any comments on that idea? How about it, Mr. Gutierrez? Also, there are a couple of large(12"-15" dia.) spots where the plaster is worn away, exposing the gunite. We figured to apply a thin coat of hydraulic cement to those areas, but one plaster company I talked to said it wasn't necessary, that their 3/16" final coat would be sufficient. Does that sound right or should we go ahead and make a hard, smooth surface below the plaster coat? Thanks
Hal

Make sure you wear the proper protective gear when sandblasting because wow it can hurt, and the dust debri also is a hassle if you inhale it, it can be fatal later. Where those worn plaster spots are, just pour reguar portland cement mixed with some sand and then roughen it up a bit with a brush or sponge. I recommen filling it before plastering because if you fill it the day of the plaster with regular plaster you may see what i call moisture spots under water and look a bit blotchy the reason being is the plaster material is not ment to go on so thick so moisture is still trapped underneath