How To Install Rigid Insulation Under Floor

This is a vitally important step as it helps prevent cold bridging.

How to install rigid insulation under floor. Semi rigid batts will need battens fixed along the joists. Installing rigid foam insulation there s two ways you can go about with foam board insulation. Flexible wools will need battens across the joists. Firstly you can apply it directly onto the house s concrete walls with the help of a construction adhesive that will hold it in place.

Rigid foams just need a few tacks to ensure they do not drop. When completed the entire slab area has a cover of rigid sheets of styrofoam. Before beginning the installation of the rigid insulation see to it that any services that are contained in the insulation are routed or cut on either side and sanded as per requirement. Place the insulation edge to edge using duct or other construction tape to hold the insulation together.

Or as demonstrated here you can cover the slab with rigid foam insulation add two layers of plywood and then add the finish flooring. Step 1 build the floors. As long as you have enough room to access the floor joist framing installing insulation under the floor is a fairly simple remedy. There are two ways to handle insulating concrete floors.

Run sections of insulation from the rim joists to the crawl space or basement floor all along each wall. Place 2 inch thick pieces of rigid styrofoam insulation on top of the plastic sheeting. Use 2 1 2 inch deck screws to drive the furring strips into the foam and the wood framing beyond. But insulating your floors is a good idea for many reasons including energy efficiency and height adjustments.

Install 1 by 3 furring strips over the insulation panels on top of each stud. The furring strips should run vertically from floor to ceiling or from eaves to rafters if you are installing them on a sloped ceiling. Lay down a moisture barrier with sheets of 6 mil plastic if you have a dirt or gravel floor. The way the insulation is installed will vary with the type and rigidity of the insulation.

Install at full depth a 25mm thick perimeter strip of the same floor insulation along all external walls. The thickness required to achieve a u value of 0 25w m on a suspended floor is. You can attach wood sleepers to the floor fill the gaps with rigid foam insulation and then apply your finish flooring. Here s what you need to know.