Two ways to insulate a brick veneer wall, from the Inside
Bill Robinson moved to New Orleans to help in the aftermath of Hurricane Katrina. he never left. He has become quite an expert in flood clean up, repair. He is currently fixing a home that had eighteen inches of flood water in it.
We asked him to check in from time to time with flood cleanup and reconstruction tips.
This home was flooded in August of 2016 and received about 18 inches of water. In this video, we will show two ways to restore the drainage plane in the brick cavity walls where the sheeting and the through-wall flashing are no longer in place.
Notice at the base of the wall the mortar has dropped to the bottom of the cavity and is covering the weep holes. We need to clean this out first.
The first part of the new drainage plane will be the PVC flashing at the bottom of the wall, to divert water that gets behind the brick to the bottom of the brick cavity and out the weep holes.
To install the drainage mat, measure between the studs, and cut the mat to fit, leaving the spaces between the studs and the brick open for spray foam later. You will need to leave a spacer between the studs and the mat to hold it in place until the spray foam is installed.
Method 1: Insulate with expanded Polystyrene foam
For the XPS detail, measure between the studs and cut the XPS so it will fit easily between the studs. We'll fill the gaps with gun foam later.
The mortar squeezed out between the bricks will stand the XPS off the wall enough to allow any water to drain to the bottom of the wall and then out through the weep holes.
Method 2: Drainage mat with spray foam
For the drainage mat cavity, spray two inches of two pound closed cell spray foam. This will give you an R13 value.
Fill the spaces between the framing and the brick for a more complete moisture barrier. This spray foam application is best done by a trained installer, using appropriate personal protective equipment.
For the XPS repair, fill all of the gaps with gun-foam.
A 100% solid compatible caulk can also be used to fill these gaps. Take plenty of time to fill all of the gaps around the XPS.
—Bill Robinson is a remodeler and construction training specialist in New Orleans, LA