Retrofit flood-resistant wall assembly
Remodelpro
| Posted in Energy Efficiency and Durability on
Proposed Wall Details:
– 2×4 treated bottom plate, untreated 2×4 framing, 1/2″ exterior plywood sheathing covered with building paper and Hardi Plank siding on the exterior (No rain screed).
– Bottom of stud cavity (First 12″ to 18″) insulated with closed cell spay foam, the balance of the wall insulated with fiberglass of rock wool.
– Bottom ( First 12″ to 18″) of interior finished with PVC wainscoting or other waterproof material. the balance of the interior wall finished with 1/2″ drywall..
In a minor flood situation (Less than 12″of water) would the framing and plywood sheathing be able to dry out without disassembly?
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Replies
Anthony,
Q. "In a minor flood situation (less than 12 inches of water) would the framing and plywood sheathing be able to dry out without disassembly?"
A. Probably, but the answer depends on how long the waters stay high. Eventually, saturated plywood can swell, buckle, and delaminate. Remember, too, that floodwater is often a nasty, toxic soup that includes chemicals, fuel oil, gasoline, and sewage.
If you want fast drying, a rainscreen gap between the siding and the sheathing would help.
i'd like to put forward the general proposition that finished basements are nuts. Why include a space that you have to design and detail on the assumption that at some point it will almost inevitably have a flood sufficiently serous to damage not only the finishes, but the structure as well? How many of the houses affected by floods experience the majority of their damage in below grade rooms? Basements are an anachronism from when they were needed for food storage. Finished basements are a high risk inclusion to a house in most situations.
Malcolm,
I'm fairly sure that Anthony is talking about an above-grade wall, not a finished basement.
Malcom,
Martin is correct that I am talking about an above grade wall and not a finished basement.
Anthony,
Seems a shame to waste my rant. Any chance you might include a basement in the future?