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Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1355
Registered: 05-2003
Posted on Wednesday, June 03, 2015 - 06:36 pm:   Edit PostDelete PostPrint Post

I specified GP's DensShield for the walls and ceiling of a Spa within a new hotel. Most of the surfaces will receive tile or stone finish. The Contractor decided to use standard type-x gyp board for the ceilings, ignoring the specs. Why he followed the specs for the walls has yet to be explained. The Architect asked if there is any coating the GC could apply over the gyp board to render it mold resistant. I said no, tell the GC to rip all the gyp board ceilings out and start over, this time following the specs - I'm not fond of this GC or this job. What really ticks me off is that the GC is blaming the specifications for not clearly stating where the DensShield was to be used....I specified it as a backer board for wet areas, and since in the center of this spa is a huge communal whirlpool, the spa is a total wet area. The architect's drawings were not clear in defining which surfaces are to receive DensShield. The Architect's solution is to retain the existing ceilings painted with an epoxy coating. Why is it Architects think Epoxy is the cure all for what ails you?

I like my answer, but my client thinks I can do better. I will explain further by telling you the Spa is a few 100 feet from the Ocean in S. FL., the drywall will expand and contract along with the joints. I don't see how a coating is going to make this assembly mold resistant when the substrate isn't. And of course the Developer wants the least expensive solution. Any suggestions would be appreciated.
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1356
Registered: 05-2003
Posted on Wednesday, June 03, 2015 - 06:40 pm:   Edit PostDelete PostPrint Post

One more thing, most of the interior walls are covered in DensShield, more than was required, perhaps the GC used up all the DensShield on the job for the walls and figured the ceilings would be ok with standard gyp board.
Nathan Woods, CSI, CCCA, LEED AP
Senior Member
Username: nwoods

Post Number: 665
Registered: 08-2005


Posted on Wednesday, June 03, 2015 - 06:49 pm:   Edit PostDelete PostPrint Post

You could have the contractor ADD a layer of moisture resistant drywall instead of demo'ing what's in place. Curious, is the soffit/ceiling framing at 12" OC? Might need to be.

Alternatively, you could perhaps use a high performance anti-fungal primer like Kilz, and then top coat it with another quality paint coating that is anti-fungal, but all you are doing is making the food source for mold hard to get, not absent altogether.
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1358
Registered: 05-2003
Posted on Wednesday, June 03, 2015 - 06:56 pm:   Edit PostDelete PostPrint Post

Nathan, unfortunately the spacing is not 12", and the framing is also not 20 gage as I specified for framing to receive backer board, its 25 gage.
Nathan Woods, CSI, CCCA, LEED AP
Senior Member
Username: nwoods

Post Number: 666
Registered: 08-2005


Posted on Wednesday, June 03, 2015 - 07:02 pm:   Edit PostDelete PostPrint Post

Time to write a non-compliance report, and call for more waste reclamation bins shipped to the jobsite
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1359
Registered: 05-2003
Posted on Wednesday, June 03, 2015 - 07:11 pm:   Edit PostDelete PostPrint Post

No reclamation bins on this job that I know of.
No non-compliance report for me to write, I'm not the architect and the Developer refused to pay me to be available during CA, any time I spend to answer questions like this one is pro-bono.

This job has been a nightmare from day one, this is the developer who told the Architect that the Project Manual was too thick, at 4" double sided, he demanded we reduce the thickness to 1-1/2".

Welcome to S. FL Architecture, for all you M.A.S.H. lovers, its meat ball surgery every day.
Steven Bruneel, AIA, CSI-CDT, LEED-AP, EDAC
Senior Member
Username: redseca2

Post Number: 481
Registered: 12-2006


Posted on Wednesday, June 03, 2015 - 07:14 pm:   Edit PostDelete PostPrint Post

You also need to worry about the backside of the standard Type-X. The good mold and moisture resistant products have improved backs and cores in addition to the upgraded face of the sheet.

I have never worked in Florida, but if the ceiling is in a pool/spa area on one side and unconditioned Florida air is on the other side there will be damp.
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1360
Registered: 05-2003
Posted on Wednesday, June 03, 2015 - 07:25 pm:   Edit PostDelete PostPrint Post

GC has offered to paint the gyp board with a SW Harmony Interior Latex Semi-Gloss paint, wow, this job gets better and better.

Steven you are correct, its not just about the facing.

What blows my mind is the GC thinks that he has complied with the Specifications, but than again the Developer did throw the revised and shortened specs in the trash bin at start of the job, apparently when bound, the Project manual measured 2 inches, my bad.
Nathan Woods, CSI, CCCA, LEED AP
Senior Member
Username: nwoods

Post Number: 667
Registered: 08-2005


Posted on Wednesday, June 03, 2015 - 07:35 pm:   Edit PostDelete PostPrint Post

Should have used Bible Paper:
http://en.wikipedia.org/wiki/Bible_paper
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1362
Registered: 05-2003
Posted on Wednesday, June 03, 2015 - 07:43 pm:   Edit PostDelete PostPrint Post

Nathan, wooooosh
I don't understand, did I miss something?
What has bible paper to do with my job, is this some sort of religious joke?
Please enlighten me?
Nathan Woods, CSI, CCCA, LEED AP
Senior Member
Username: nwoods

Post Number: 668
Registered: 08-2005


Posted on Wednesday, June 03, 2015 - 07:49 pm:   Edit PostDelete PostPrint Post

If your product is being measured by thickness instead of content, and you have to get down to a certain arbitrary value of less than 1.5", you could use Bible Paper (AKA: India Paper, lightweight offset paper, premium book paper) to accomplish that. Here is another link: http://desktoppub.about.com/od/glossary/g/biblepaper.htm
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1364
Registered: 05-2003
Posted on Wednesday, June 03, 2015 - 08:01 pm:   Edit PostDelete PostPrint Post

Seriously Nathan, I refuse to ever meet the ridiculous requirement of Project Manual thickness ever again. I will be the first to agree that Project Manuals are too long, but I can't believe anyone would need to measure the thickness of their Project Manual in order to appease a client.

However, I enjoy learning new things, and I've never heard of Bible Paper, so thanks for that info.
Ronald J. Ray, RA, CCS, CCCA
Senior Member
Username: rjray

Post Number: 139
Registered: 04-2004
Posted on Wednesday, June 03, 2015 - 09:59 pm:   Edit PostDelete PostPrint Post

Tnemec Company, Inc. has a system that would protect the exposed surface from mold and mildew, but as stated above, that does nothing for the core and back face. The Tnemec system is Series 151 primer and Series 158 top coat. Verify with your local Tnemec rep.
Michael Chusid, RA FCSI CCS
Senior Member
Username: michael_chusid

Post Number: 42
Registered: 10-2003


Posted on Thursday, June 04, 2015 - 02:44 am:   Edit PostDelete PostPrint Post

Bible paper is a costly solution. Print the project manual with 8 pt type. The developer figures it all "fine print" anyways.
Michael Chusid, RA FCSI CCS
www.chusid.com www.buildingproduct.guru
Michael Chusid, RA FCSI CCS
Senior Member
Username: michael_chusid

Post Number: 43
Registered: 10-2003


Posted on Thursday, June 04, 2015 - 02:46 am:   Edit PostDelete PostPrint Post

On a more serious note, what is above the ceiling? Will it be ventilated? Cooled? If it ventilated and hot, you may be able to avoid condensation in or on the gyp board.
Michael Chusid, RA FCSI CCS
www.chusid.com www.buildingproduct.guru
Steven Bruneel, AIA, CSI-CDT, LEED-AP, EDAC
Senior Member
Username: redseca2

Post Number: 482
Registered: 12-2006


Posted on Thursday, June 04, 2015 - 01:50 pm:   Edit PostDelete PostPrint Post

There was an article in the CSI magazine many years ago about "Natatorium" failures due to moisture and corrosion issues. I last remember sharing it with a client for a project with an indoor pool way back in 2005 or so and I recall it took some search for it even then. It might be worth tracking down.

Some scary stuff like a structural roof failure and some bizarre stuff like a wall-mounted stainless steel clad drinking fountain that looked fine at first glance but when you opened it, all of the interior components had rusted away to a pile of junk in the bottom of the enclosure.
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1366
Registered: 05-2003
Posted on Thursday, June 04, 2015 - 02:03 pm:   Edit PostDelete PostPrint Post

Steven, I know that article, by Catherine Houska, I have a PDF on file as I've had to specify stainless steel pools and hot tubs on high rise coastal projects. The article talks mostly about using stainless steel for pool construction, not really Natatoriums, all the pics in the article are open air pools.

I would be scared to death to specific a Natatorium, thankfully I've not had that opportunity as of yet.
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1367
Registered: 05-2003
Posted on Thursday, June 04, 2015 - 02:08 pm:   Edit PostDelete PostPrint Post

Most of the GYP BD manufacturer reps I've reached out to recommend applying a mold resistant board over the existing drywall, no one is willing to offer an off the record out of the box solution, can't blame them, I still like my solution of tearing it all out. Its up to the architect and engineer to figure out if the installed framing system can support the added load.

Thanks to you all for responding.
Robin E. Snyder
Senior Member
Username: robin

Post Number: 597
Registered: 08-2004
Posted on Thursday, June 04, 2015 - 02:42 pm:   Edit PostDelete PostPrint Post

What about a vapor impermeable paint? It that is an option, I can email you some info
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1371
Registered: 05-2003
Posted on Thursday, June 04, 2015 - 02:55 pm:   Edit PostDelete PostPrint Post

Robyn, please send me the info, I will reach out to the manufacturer as I am interested in their warranty and limitations. Warren Barber from National Gypsum just emailed me some suggestions which I am reviewing. Warren's comment: "If you were to coat the face with Custom’s Red Guard or Laticrete’s Hydroban as a water proofing coating, it would keep moisture away from the board, No moisture, no mold."
Robin E. Snyder
Senior Member
Username: robin

Post Number: 599
Registered: 08-2004
Posted on Thursday, June 04, 2015 - 03:01 pm:   Edit PostDelete PostPrint Post

Neither of those products are vapor barriers, so you need to assess the design and decide if a vapor barrier is required. Also, what is the finish? If it’s a ceiling, likely not tile. Will forward you the info in a separate email.

email me - robin@spectraspecs.com
ken hercenberg
Senior Member
Username: khercenberg

Post Number: 908
Registered: 12-2006


Posted on Thursday, June 04, 2015 - 03:21 pm:   Edit PostDelete PostPrint Post

Considering the level of quality you seem to be getting I'd be very hesitant to trap moisture in your ceiling assembly. I agree with the 'tear it out' attitude. Either that or they can pay for an air handling unit to provide a constant stream of ventilation and dehumidification above the ceiling (and the energy costs to run it) and the waterproof coating at the underside.

Realistically your client is probably best off just being on record to the developer that the assembly provided does not meet the Contract Docs and that future issues can reasonably be expected (I wouldn't enumerate further).
Jerome J. Lazar, RA, CCS, CSI, SCIP
Senior Member
Username: lazarcitec

Post Number: 1374
Registered: 05-2003
Posted on Thursday, June 04, 2015 - 03:47 pm:   Edit PostDelete PostPrint Post

Thanks Ken, your last statement would describe the entire project, this is the project where the developer insisted the Project Manual thickness be reduced...its been a problematic job from day one and as I've said the Developer refused to extend my services during construction administration, so all this time helping the architect solve problems has been pro bono. I must be slipping in my old age, this is one of those clients that has gone sans specs.

Still I believe in loyalty and in the past this has been a good client. Its amazing too because one of the partners has told me that he has learned how valuable specs are for construction, seems that his revelation has not translated into action.
John Regener, AIA, CCS, CCCA, CSI, SCIP
Senior Member
Username: john_regener

Post Number: 745
Registered: 04-2002


Posted on Saturday, June 06, 2015 - 10:59 am:   Edit PostDelete PostPrint Post

For school shower rooms and interior swimming pools, I specify a water-based epoxy coating system. My understanding is the epoxy coating system has a low perm rating. Which takes care of the field area but not penetrations. Of course, the objection is cost. The painter must mix multi-component primer and finish coating.

It comes down to, if you want cheaper oats, buy the kind that have been through a horse once.

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