Air sealing CMU walls that are exposed inside and out in tropical climate
I’m looking for an effective membrane and/or application to air seal a home with walls made up entirely of exposed CMU.
I’m working on the mechanical systems design and spec for the home and advising the builder to lower the infiltration so we can keep latent loads to a minimum. I am not interested in R-Value.
The 5,000 s.f. home is located on a very small private island just north of Exuma, Bahamas, and it is surrounded by ocean. The interior and exterior finish of the home is exposed CMU.
Design temperatures range is between 60 F and 90 F, and the RH range is between 50 and 90%. I’m using “Nassau AP New, BS” weather station as a basis, if this helps, and adjusting it for more exposed conditions that’s about 150 miles south by southeast (slightly higher temp and RH).
There are many good options that I’m already aware of, but I just want to know if I’m missing an opportunity with something more appropriate to this application and location.
Thank you all, in advance.
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Replies
Chris,
The standard material for air sealing CMU walls is plaster. It can be installed on the interior (in which case it is usually called plaster) or on the exterior (in which case it is usually called stucco) or both.
Fortunately, construction workers in the Caribbean and nearby islands are very familiar with stucco.
Exterior stucco is usually cementitious (Portland-cement-based), but you can use a synthetic stucco if you prefer. Interior plaster can be cemetitious or plaster-based.
If you need an on-site consultant or surpervisor for construction work in the Bahamas, my per-diem rates are reasonable.