Learn the Basics of Installing Rigid Flat Roof Insulation for the Perfect Seal

Installing rigid foam board insulation on exposed ceilings directly beneath flat roofs can be a great way to reduce energy bills and create a more comfortable home. To install this insulation, you will need to measure and cut the foam to fit perfectly between joists, place the foam against the ceiling, seal the edges, and create a vapor barrier. This article will provide step-by-step instructions to help you complete the job properly.

First, measure between the joists and take perfect measurements. It is important to get the dimensions just right, as the joists will be used to hold the foam in place. You can then use a utility knife to cut the foam to the exact size needed. To make the process easier, make a straight line across the foam with a straight edge and score the foam there. Once you have cut far enough into the foam, you can snap the pieces along the scored line.

Once the foam is cut to size, a step ladder may be necessary to reach the ceiling. Most insulation of this type is found in 2-inch panels, but they can also be found in other sizes to accommodate different ceiling depths. Install the foam sheets by pressing each piece against the top of the ceiling and butting them up against each other tightly.

To create an airtight seal along the edges of the foam, spray foam should be used. Spray foam comes in a can and can be found at most home-improvement stores. Once you have sprayed the foam along the seams and edges, a vapor barrier needs to be put in place. This can be done by covering the ceiling with plastic sheeting. Start from one corner of the room and use a staple gun to secure the plastic to the joists. Be sure to keep the plastic taut and overlap it one complete cavity.

Alternatively, you can hang a drywall ceiling to create a more finished look. This will take more time, but will provide a better result.

Once you have followed all the above steps, you should have successfully installed rigid flat roof insulation. This type of insulation will be beneficial for both your energy bills and the comfort of your home.