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terri burgess Posted: Apr 27, 2009 12:23 PM	Indoor Pool/Arena Hi, i am insulating an indoor hockey arena with an adjoining indoor pool. They are being heated/cooled Geothermally. The arena was constructed with wood, with a metal roof and siding. The pool house will also be made of wood, with board and batten exterior walls, and a shingle roof. (interior walls undetermined at this time) I am wondering what the best type of insulation to use for both buildings would be. I need to avoid any condensation/mildew problems from humidity. Any help would be greatly appreciated. thnx chris.
mason Posted: Apr 27, 2009 12:42 PM	Closed cell foam would work best in a swimming pool as it has a lower perm rating and is water resistant. You would need to put a vapor retarder coating over the foam and perform hygrothermal modeling to determine how much foam to use.
terri burgess Posted: Apr 27, 2009 01:01 PM	how does a hygrothermal test determine how much foam to use? what is the formula i would use? and what about the Hockey Arena? how should i insulate the ceiling (which is not in yet, but will most likey be metal as well)and walls? Do i have to use spray foam, or will cellulose work as well? (in the attic) In other words, is it imperative that i use spray foam everywhere?
mason Posted: Apr 27, 2009 04:44 PM	Hygrothermal modeling consists of determining the potential moisture condensation that a specific building design would have by considering the temperature and humidity inside and out plus the type of building materials (insulation effectiveness and permeability) plus the use of the building, (swimmming pool, office space, freezer, etc. It can be done using a psychrometric chart but there are software tools (such ans WUFI and MOIST) that provide more dynamic points of reference to help predict how much insulation is to be used to reduce the potential for condensation. It takes into consideration the building materials, climate of the area, vapor retarders, etc. to determine if the wall or ceiling will accumulate water or if it will allow water vapor to pass through it without condensing. Your supplier might have a copy of the software or you can pay someone to do the calculations. I typically charge around $300 for a WUFI simulation. I don't like using permeable insulation in high humidity environments. Cellulose has a higher perm rating than open cell sprayfoam and much higher than closed cell foam. You need to separate the interior environment and the exterior environment (temperature and humidity). Sprayfoam will effectively do that. In the case of a swimming pool or hockey arena, the high humidity will be coming form the inside making a vapor drive toward the exterior of the building. Using a closed cell sprayfoam will air seal the building while effectively separating the inside and the outside environment. But since there is always a constant vapor drive in one direction, the sprayfoam would need a vapor retarder coating over it (on the inside of the building over the foam). This would prevent the water vapor from going through the foam and condensing on the inside of the exterior metal. Depending on how cold it is outside, you might need anywhere from 3-5 inches of sprayfoam to effectively prevent condensation against the metal.
terri burgess Posted: Apr 27, 2009 09:54 PM	sure i will pay the 300.00, what else do u need to know....u can email at ctamp@zing-net.ca to arrange pymt...thnx
terri burgess Posted: May 01, 2009 10:23 PM	Mason, i still haven't received an email from your to provide pymt for the hydrothermal testing. Again, my email is ctamp@zing-net.ca thnx
mason Posted: May 04, 2009 09:14 AM	Terri, I am on the road this week until May 9, I will contact you when I get back about doing a Wufi Simulation
terri burgess Posted: Jul 21, 2010 08:49 AM	Hi Mason, its Terri, my Arena/pool was hit by a Tornado and demolished! I am rebuilding and re-read your post here. I thought 2lb spray foam did NOT need a vapour retarder as it has a very small pearm rating. Is it imperative? which one would u reccomend? can i spray it on? Please elaborate, thnx Terri.
mason Posted: Jul 22, 2010 10:42 AM	Terri, Closed cell SPF is considered a relative vapor retarder in most types of construction and building use. However if there is a constant vapor drive in one direction, then the foam would require a vapor barrier type vapor retarder such as asphalt or butyl rubber coating. Examples would be cold storage facilities and high humidity environments such as swimming pools. You would place the vapor barrier/retarder coating on the warm side of the insulation (or the high humidity side depending on the interior or exterior climate). Check out the following technical document at sprayfoam.org AY 118 Moisture Vapor Transmission.
terri burgess Posted: Jul 22, 2010 03:31 PM	Mason,i'm not sure if i told u but, i sprayed 4 inches of CC in the pool area and was assured i did not need to put a vapour retarder as well. Does this make sense? I was also told to spray a Mold inhibitor, is there a product that does both if needed? thnx
mason Posted: Jul 23, 2010 11:33 AM	If you sprayed foam to the underside of a metal roof deck then a vapor retarder would be required over the foam. The metal is a vapor barrier type vapor retarder. The foam will allow some water vapor to pass through it. If the high humidity is always on the pool side of the structure then the water vapor flow will always be going towards the metal deck through the foam. Eventually, enough water vapor would accumulate at the sprayfoam metal deck interface to reach the dewpoint and condensation would occur.
terri burgess Posted: Jul 23, 2010 11:46 AM	No Mason, the pool is a wooden structure, both the walls and the roof, the ice arena is constructed of metal with a metal rood deck. Does it make a differnce? Do they both need a vapour retarder, or just the pool area? Can u reccommend a good spray on type. thnx
mason Posted: Jul 25, 2010 09:02 AM	The wooden roof deck will allow water vapor to pass through it. So if the foam is thick enough to separate the interior temperature and the exterior temperature, the water vapor should pass harmlessly through the foam and wood without condensing. But, in the ice arena, the metal would act as a vapor barrier stopping any water vapor heading in that direction. So, you would want a vapor barrier type coating over the foam. I would recommend some hygothermal calculations on both structures (such as a WUFI simulation) to verify the thickness of the foam and the type of vapor retarder coatings.
terri burgess Posted: Jul 25, 2010 10:33 AM	Thnx Mason. If i placed 6 mil poly on the 2x6 framing in the pool area before i put the cedar ceilings and outdoor stucco on the walls, would that help or hinder the condensation issues? I am also installing a Low E ceiling in the arena about 14 inchs below the roof deck and cc foam. This is supposed to equalize the temperatures just under the low E ceiling and just under the roof deck, which, i am told will help eliminate any condensation issues. Do u think this will work? thnx Terri
mason Posted: Jul 26, 2010 02:22 PM	6 mil poly is a vapor barrier/retarder and if used on the exterior side of the insulation, would require a vapor retarder over the foam on the inside. Just remember, a vapor retarder will slow or effectively stop water vapor flow through it. If the vapor flow is always in one direction then the water stops there. If the temperature is colder at that spot it can reach its dewpoint and cause condensation. ccSPF slows but does not stop water vapor flow. If water vapor goes in both directions, ccSPF can be used typically without a vapor barrier/retarder> If the other building materials also allow a slow controlled flow of water vapor similar to the ccSPF then again a vapor barrier/retarder is not needed. However, if you have a vapor drive in one direction towards the insulation and there is a vapor retarder/barrier such as poly or metal on the other side of the insulation then you would need another vapor barrier/retarder on the surface of the foam. Sorta of like a insulated metal panel used in cold storage applications. The key things to remember are 1. Does the water vapor flow in both directions or in one? 2. If in one direction, what is the direction? 3. If it is in one direction is there a vapor retarder material that would effectively stop most of the water vapor? 4. Is there insulation behind the vapor retarder or is the vapor retarder after the insulation? If the water vapor flows through the insulation first then hits a vapor barrier/retarder, it will condense if the substrate temperature is cool enough. (example indoor ice arena with insulation, then metal deck in cooler climates.) If the water vapor flows through insulation and then a permeable building material (such as wood or concreted), it most likely will not condense. (Example swimming pool with insulation then wood decking.) If the water vapor flows through insulation then poly film and then wood, it may condense against the poly depending on the outside temperature (cool) Again do a WUFI simulation as I suggested to specifically know the situation at your facility.

Author

Comments

terri burgess

Posted: Apr 27, 2009 12:23 PM

Indoor Pool/Arena

Hi, i am insulating an indoor hockey arena with an adjoining indoor pool. They are being heated/cooled Geothermally. The arena was constructed with wood, with a metal roof and siding. The pool house will also be made of wood, with board and batten exterior walls, and a shingle roof. (interior walls undetermined at this time) I am wondering what the best type of insulation to use for both buildings would be. I need to avoid any condensation/mildew problems from humidity. Any help would be greatly appreciated. thnx chris.

mason

Posted: Apr 27, 2009 12:42 PM

Closed cell foam would work best in a swimming pool as it has a lower perm rating and is water resistant. You would need to put a vapor retarder coating over the foam and perform hygrothermal modeling to determine how much foam to use.

terri burgess

Posted: Apr 27, 2009 01:01 PM

how does a hygrothermal test determine how much foam to use? what is the formula i would use? and what about the Hockey Arena? how should i insulate the ceiling (which is not in yet, but will most likey be metal as well)and walls?
Do i have to use spray foam, or will cellulose work as well? (in the attic) In other words, is it imperative that i use spray foam everywhere?

mason

Posted: Apr 27, 2009 04:44 PM

Hygrothermal modeling consists of determining the potential moisture condensation that a specific building design would have by considering the temperature and humidity inside and out plus the type of building materials (insulation effectiveness and permeability) plus the use of the building, (swimmming pool, office space, freezer, etc. It can be done using a psychrometric chart but there are software tools (such ans WUFI and MOIST) that provide more dynamic points of reference to help predict how much insulation is to be used to reduce the potential for condensation. It takes into consideration the building materials, climate of the area, vapor retarders, etc. to determine if the wall or ceiling will accumulate water or if it will allow water vapor to pass through it without condensing.

Your supplier might have a copy of the software or you can pay someone to do the calculations. I typically charge around $300 for a WUFI simulation.

I don't like using permeable insulation in high humidity environments. Cellulose has a higher perm rating than open cell sprayfoam and much higher than closed cell foam. You need to separate the interior environment and the exterior environment (temperature and humidity). Sprayfoam will effectively do that. In the case of a swimming pool or hockey arena, the high humidity will be coming form the inside making a vapor drive toward the exterior of the building. Using a closed cell sprayfoam will air seal the building while effectively separating the inside and the outside environment. But since there is always a constant vapor drive in one direction, the sprayfoam would need a vapor retarder coating over it (on the inside of the building over the foam). This would prevent the water vapor from going through the foam and condensing on the inside of the exterior metal.

Depending on how cold it is outside, you might need anywhere from 3-5 inches of sprayfoam to effectively prevent condensation against the metal.

terri burgess

Posted: Apr 27, 2009 09:54 PM

sure i will pay the 300.00, what else do u need to know....u can email at ctamp@zing-net.ca to arrange pymt...thnx

terri burgess

Posted: May 01, 2009 10:23 PM

Mason, i still haven't received an email from your to provide pymt for the hydrothermal testing. Again, my email is ctamp@zing-net.ca
thnx

mason

Posted: May 04, 2009 09:14 AM

Terri,

I am on the road this week until May 9, I will contact you when I get back about doing a Wufi Simulation

terri burgess

Posted: Jul 21, 2010 08:49 AM

Hi Mason, its Terri, my Arena/pool was hit by a Tornado and demolished! I am rebuilding and re-read your post here. I thought 2lb spray foam did NOT need a vapour retarder as it has a very small pearm rating. Is it imperative? which one would u reccomend? can i spray it on? Please elaborate, thnx Terri.

mason

Posted: Jul 22, 2010 10:42 AM

Terri,

Closed cell SPF is considered a relative vapor retarder in most types of construction and building use. However if there is a constant vapor drive in one direction, then the foam would require a vapor barrier type vapor retarder such as asphalt or butyl rubber coating.

Examples would be cold storage facilities and high humidity environments such as swimming pools. You would place the vapor barrier/retarder coating on the warm side of the insulation (or the high humidity side depending on the interior or exterior climate).

Check out the following technical document at sprayfoam.org AY 118 Moisture Vapor Transmission.

terri burgess

Posted: Jul 22, 2010 03:31 PM

Mason,i'm not sure if i told u but, i sprayed 4 inches of CC in the pool area and was assured i did not need to put a vapour retarder as well.
Does this make sense? I was also told to spray a Mold inhibitor, is there a product that does both if needed? thnx

mason

Posted: Jul 23, 2010 11:33 AM

If you sprayed foam to the underside of a metal roof deck then a vapor retarder would be required over the foam. The metal is a vapor barrier type vapor retarder. The foam will allow some water vapor to pass through it. If the high humidity is always on the pool side of the structure then the water vapor flow will always be going towards the metal deck through the foam. Eventually, enough water vapor would accumulate at the sprayfoam metal deck interface to reach the dewpoint and condensation would occur.

terri burgess

Posted: Jul 23, 2010 11:46 AM

No Mason, the pool is a wooden structure, both the walls and the roof, the ice arena is constructed of metal with a metal rood deck. Does it make a differnce? Do they both need a vapour retarder, or just the pool area?
Can u reccommend a good spray on type. thnx

mason

Posted: Jul 25, 2010 09:02 AM

The wooden roof deck will allow water vapor to pass through it. So if the foam is thick enough to separate the interior temperature and the exterior temperature, the water vapor should pass harmlessly through the foam and wood without condensing.

But, in the ice arena, the metal would act as a vapor barrier stopping any water vapor heading in that direction. So, you would want a vapor barrier type coating over the foam.

I would recommend some hygothermal calculations on both structures (such as a WUFI simulation) to verify the thickness of the foam and the type of vapor retarder coatings.

terri burgess

Posted: Jul 25, 2010 10:33 AM

Thnx Mason. If i placed 6 mil poly on the 2x6 framing in the pool area before i put the cedar ceilings and outdoor stucco on the walls, would that help or hinder the condensation issues?

I am also installing a Low E ceiling in the arena about 14 inchs below the roof deck and cc foam. This is supposed to equalize the temperatures just under the low E ceiling and just under the roof deck, which, i am told will help eliminate any condensation issues.

Do u think this will work? thnx Terri

mason

Posted: Jul 26, 2010 02:22 PM

6 mil poly is a vapor barrier/retarder and if used on the exterior side of the insulation, would require a vapor retarder over the foam on the inside. Just remember, a vapor retarder will slow or effectively stop water vapor flow through it. If the vapor flow is always in one direction then the water stops there. If the temperature is colder at that spot it can reach its dewpoint and cause condensation.

ccSPF slows but does not stop water vapor flow. If water vapor goes in both directions, ccSPF can be used typically without a vapor barrier/retarder>

If the other building materials also allow a slow controlled flow of water vapor similar to the ccSPF then again a vapor barrier/retarder is not needed.

However, if you have a vapor drive in one direction towards the insulation and there is a vapor retarder/barrier such as poly or metal on the other side of the insulation then you would need another vapor barrier/retarder on the surface of the foam.

Sorta of like a insulated metal panel used in cold storage applications.

The key things to remember are
1. Does the water vapor flow in both directions or in one?
2. If in one direction, what is the direction?
3. If it is in one direction is there a vapor retarder material that would effectively stop most of the water vapor?
4. Is there insulation behind the vapor retarder or is the vapor retarder after the insulation?

If the water vapor flows through the insulation first then hits a vapor barrier/retarder, it will condense if the substrate temperature is cool enough. (example indoor ice arena with insulation, then metal deck in cooler climates.)

If the water vapor flows through insulation and then a permeable building material (such as wood or concreted), it most likely will not condense.
(Example swimming pool with insulation then wood decking.)

If the water vapor flows through insulation then poly film and then wood, it may condense against the poly depending on the outside temperature (cool)

Again do a WUFI simulation as I suggested to specifically know the situation at your facility.

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