The kneewalls in this Allenhurst, NJ home were poorly insulated, causing uncomfortable rooms year-round. During the summer, radiant heat from the roof transferred through the uninsulated kneewalls, making the upstairs rooms excessively hot. In the winter, cold air traveled through the floor joists and kneewall cavities, creating cold floors, drafts, and uneven temperatures throughout the upper level.
Solution
To solve the problem, we installed SilverGlo rigid foam blocks between the ceiling joists beneath the adjoining wall to stop cold air from traveling through the floor cavities. Each block was sealed with spray foam to eliminate drafts and cold floors. We then air sealed by spray foaming the wall plates, top plates, and all gaps around wires, pipes, and other penetrations. Because of the home's unique construction and numerous open cavities, we installed SilverGlo insulated foam boards on the adjoining walls instead of the roof rafters. After sealing all the seams with spray foam, we blew in TruSoft cellulose insulation to an R-60 level, creating a well-insulated attic kneewall that reduces heat transfer, keeps conditioned air where it belongs, and improves comfort in every season.
Project Summary
Products: SilverGlo Rigid Foam Boards with a Radiant Barrier, ZypFoam Sealant, & TruSoft Cellulose Insulation
The top floor can become unbearably hot in the summer as the sun's radiant heat transfers through the roof, into the kneewalls, and eventually into the living spaces. During the winter, cold air infiltrates the floor joist bays, creating cold floors, uncomfortable drafts, and uneven temperatures throughout the upper level.
We create an access point into the kneewall so we can reach the entire cavity, properly air seal the area, and install insulation to improve comfort, energy efficiency, and temperature control throughout the home.
Entering the kneewall, we discovered little to no insulation throughout the space. The kneewall extends around to the right, and as we inspect both sides, we can see there is no insulation barrier to prevent radiant heat from transferring through the adjoining walls during the summer. Looking down into the floor joist bays, we also found no insulation to stop cold air infiltration, which can lead to cold floors, drafts, and uncomfortable rooms during the winter months.
We install SilverGlo rigid foam blocks beneath the adjoining walls to seal the open joist bays and prevent cold air from entering the floor cavities, helping eliminate cold floors and drafts. We then use air-sealing foam to seal around the foam blocks, creating an airtight barrier that stops air infiltration into the adjoining rooms. Finally, we air seal all wall plates, top plates, cracks, gaps, and any openings around wires or pipe penetrations to further improve the home's comfort and energy efficiency.
Installing SilverGlo foam boards with a radiant barrier along the adjoining walls helps reflect radiant heat away from the living space, keeping unwanted heat out and creating more comfortable conditions in the conditioned rooms. We also use air-sealing foam to seal all gaps, cracks, and penetrations, helping prevent air leakage and improve overall energy efficiency.
Installing SilverGlo foam boards with a radiant barrier along the adjoining walls helps reflect radiant heat away from the living space, keeping unwanted heat out and creating more comfortable conditions in the conditioned rooms. We also use air-sealing foam to seal all gaps, cracks, and penetrations, helping prevent air leakage and improve overall energy efficiency.
This is the same kneewall where we are installing blown-in cellulose insulation to achieve the optimal R-60 insulation level. This added insulation helps reduce heat transfer, improve energy efficiency, and maintain more consistent, comfortable temperatures throughout the living spaces.
This is the same kneewall where we are installing blown-in cellulose insulation to achieve the optimal R-60 insulation level. This added insulation helps reduce heat transfer, improve energy efficiency, and maintain more consistent, comfortable temperatures throughout the living spaces.
