Retractable pool enclosure up against an existing house
We are in a 5A climate zone, near Chicago. We wanted to add a retractable pool enclosure up against an existing house that would be used year round. http://www.libart.com/evolution-lean-to-structures
The existing house has a wall construction what has fiber cement siding, 1″ rigid insulation with taped seams, Tyvek, 5/8″ plywood, 2×6 framing with open cell insulation and drywall on the interior. See attached image. Keep in mind that this wall was build 9 or so years ago.
The interior of the house would be conditioned but so will the enclosed pool air although it would be a bit warmer and substantially more humid due to the pool. There probably will be a dehumidification system for the pool area but I think that would not completely solve this problem.
Our concern is with having potentially warm and humid air up against the existing house year round and how that affects the existing walls. We are planning on removing the existing siding and replacing it with impregnated fiber cement (significantly different than typical cement fiberboard) to help with durability. http://www.fibercementproducts.com/blog/?page_id=400 At that point the rigid insulation would be exposed and we could modify that surface as needed.
Additionally, we are building a new pool house area that would essentially have the same condition except we can build the wall from scratch correctly to address these conditions. Any feedback what would be ideal for the new walls would be great as well. We would rather get this wall built correctly than worry about cost.
Thanks in advance
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Replies
Nathan,
The great danger with pool enclosures is that warm, humid interior air will contact cold building components during the winter. The wall between your pool and the rest of the house won't be experiencing much of a delta-T (difference in temperature), so the details there aren't risky.
However, if you build the other three walls and roof of your pool enclosure the wrong way, the structure can rot very quickly.
If you are building a new pool house, I advise you to place all of the insulation -- in this case, rigid foam -- on the exterior side of the wall and roof sheathing, PERSIST style. There should be a bullet-proof air barrier and vapor barrier on the exterior side of the wall and roof sheathing before this installation is installed -- usually a peel-and-stick membrane like Grace Ice and Water Shield.
The actual pool enclosure would be an aluminum frame with insulated glass. I know there is a chance there could be condensation on the glass surface but the pool enclosure frame has gutters built in to direct the water downward. The new attached pool house, however would be stick built and would be detailed to handle the various conditions as needed.
The tricky thing is in the pool house area that would most likely be open to the humid pool air for most of the time. The exterior walls of the pool house would also be exposed to the winter temps.
I attached some renderings for reference.