What’s the best way to dry this project?
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Hi All,
I have a new build going up in southern WI (climate zone 5 or 6a). The house is currently quite humid/wet as the drywall was just finished. I’m wondering what best strategy is for getting it to dry out. We don’t have electricity (aside from temp) or gas connected yet so can’t run the furnace or ducted dehumidifier (hoping for services to be connected next week, but at the mercy of the local energy company). The house is ~3000sq ft. Outside its 30degF with 74%RH. Inside it’s 75degF with 95%RH. We have a propane heater, several fans and a small dehumidifier running. The house is of course very well insulated. Wondering if opening windows will be productive or counter? I don’t want the temp to drop in the house much but also need to provide an avenue for moisture to leave. Thoughts on how to balance that best? Appreciate any advice.
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Replies
New construction takes a loooooong time to dry out literally tons of hygrophilic buidling materials. Sounds like you're about to paint, which brings another slosh just as the drywall finally dried. Could be the biggest culprit is the concrete foundation, which seems like it keeps things humid for months. Need lots of heat, but an unvented portable heater also dumps lots of moisture. On days that seem a little drier outside, I'd crack the windows. But you won't make serious progress until you get power to run sealed combustion (or heat pump) HVAC including dehumidifier and/or continuous HRV during these winter months.
Deleted
Can we assume the propane heater is of the unvented variety?
If so, using unvented heaters is really working against your goal of drying out the place. Every pound of propane burned releases 1.6 pounds of water inside the house.
https://www.quora.com/How-many-liters-of-water-is-formed-when-40g-of-propane-is-burned#:~:text=The%20Combustion%20Constant%20Table%20in,inert%20gas%20in%20that%20process).
Switching to an outdoor electric generator powering indoor electric heaters will use much more fuel but will stater drying the house.
You are likely pouring 50 gallons of water a day into the house.
Walta
This is where I like to point out that dehumidifiers are highly efficient space heaters. All of the latent heat in the water they remove is pumped into the house, they have a COP that makes heat pumps jealous.
YES, delay accepting delivery of your hard wood flooring.
Do not even consider installing the hardwood before the home heating and cooling systems are operational and the wintertime relative humidity is below 40%
If you install dry hardwood floors in a damp house they will swell up and buckle up in the center.
Ideally after the home has been heated long enough to dry out mostly (40% RH or so) the open boxes of flooring would be spread in every room and allowd to acclimate for 10 days before being installed.
Walta