Choose between window condensation or gaps in hardwood planks?
I built a new home in 2017. This is our first winter living in the home, and I’m running into a humidity problem.
In the fall I noticed that my 5″ wide solid oak hardwood floor had some millimeter gaps between the planks. As any concerned homeowner would do, especially for a brand new home, I researched why these gaps were happening. After doing a little research I learned that hardwood flooring can shrink when its relative humidity is below 33%. This was a sign of relief as something could actually be done to remedy the problem. So I purchased a humidifier and cranked it up to 43% RH. Once the entire home’s RH got up to around 43%, that solved the problem. A lot of the gaps shrank and the home was more comfortable to live in in general. However increasing the humidity caused an entirely new problem. That is, window condensation started forming on my double pane windows. I live in Cleveland, Oh and the temperature of this particular week was anywhere from 10 – 30 deg F. So again, I researched why this window condensation was occurring. And again, and come to find out, condensation on the windows is a sign of too much humidity in the home. Honeywell actually recommends that Relative Humidity in the home be no higher than 35% when its 20 deg outside, no higher than 30% when it’s 10 degs outside, and no higher than 25% when it’s 25 degs outside.
So you can see the problem here. Too much humidity can cause windows and interior wall cavities to condense. But on the other hand, too little humidity will cause hardwood floor gapping problems.
Does that mean I have to live with one of these problems. Are there any solutions to addressing both of these problems simultaneously?
More notes about the home
– Its got 1″ closed cell foam along with blown in cellulose in 6″ wall cavities. Also, a 1″ thick layer of Roxul covers the exterior of the house.
– The heating is in-floor radiant heat
– The home has an ERV unit installed.
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