Foam Insulation Inside Block Walls

The foam is injected under pressure into the empty cores of masonry walls.

Foam insulation inside block walls.

The variety of concrete masonry wall constructions provides for a number of insulating strategies including. Foam board insulation is easy to cut with a circular saw with a masonry blade or scored with a utility knife and snapped like you would drywall. Available in large three by five or four by eight sizes the panels. Remove all the trim from the exterior walls window and door casings baseboards crown molding you name it and rip the drywall and studs off the block walls.

It can be sprayed or injected into walls and it expands to fill the wall cavity even the smallest crevices and eventually hardens. Installing foam in concrete block is a great way to insulate a house where there is no room to install insulation on the exterior or interior of the concrete block. When insulating concrete block walls pressure forces the foam from one core into adjacent cavities flowing both vertically and horizontally sealing even the smallest cracks and fissures. This type of insulation can be more expensive than loose fill insulation.

You want spray foam insulation in these walls but normally spray foam is sprayed as an expanding seal. Leave the floor above it uninsulated vapor seal the ground below with polyethylene and a thin concrete slab insulate the walls with a foam based insulation such as 4 in. Then to account for the foam s additional thickness add jamb extensions to the windows and doors and fur out around their openings. In these cases both sides of the wall are up and you want to get an expanding foam inside without tearing down 1 side or the other.

Now as you glue the panels to the exposed concrete blocks leave a inch gap at the floor and ceiling and cut holes in the panels to fit around outlets and wall switches. Courtesy of ben rumery. To attach the insulation you can use screws with large washers a special adhesive made for adhering foam board insulation or for smaller pieces you can seal them in with caulk or spray foam. If there s nothing in the walls read slow rise below.

Of unfaced expanded polystyrene r 15 that allows the foundation to dry inward and condition the space with air from inside the house. Here s how to do this. Interior insulation insulated cavities insulation inserts foamed in place insulation granular fills in block core spaces and exterior insulation systems.