Adding panels of insulation to the sheathing is a legit way to increase the energy performance of a house. Not only does foam add R-value, it also breaks the thermal bridge created by the building components. However, a common problem is that window flanges cannot be installed directly over foam, and furring out the openings with wood bucks will create cold spots prone to condensation and mold.
ThermalBuck is designed to eliminate that problem by replacing wood bucks. It’s made from foam wrapped in a poly shell. This foam sandwich has more than enough compression strength, which prevents a window from twisting when fastened tightly to the wall. ThermalBuck is lightweight, easy to install, and costs about $50 per opening.
Go to the ThermalBuck website for more information or give them a call at 1-888-814-BUCK.