How to Beat the Maryland Summer Heat
Look to building science and a proper assessment to help you make the right improvement choices for home comfort. A new HVAC system is likely not the right solution for a cooler home in summer.
Effective Insulation is Two Parts
Most insulation (with the exception of spray foam and rigid foam board) does not stop air flow. The most cost effective insulation solutions for a house in Maryland requires a separate air barrier or "skin" to stop the flow of air. For the air barrier itself to be effective, it must be contiguous and continuous across the entire building envelope, with all holes and cracks fully sealed, and it must be perfectly aligned with the insulation.
You need both parts of the jacket to make it work the best. The same goes for the insulation around a Maryland house.
Air Sealing & Insulation Go Hand in Hand for Comfortable Maryland Homes
Building Performance Institute
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