Download a copy of our RetroFit Installation Guide

Before installation of the NUDURA Insulation Technology panels, remove any excess concrete debris that RetroFit Installation Figure 1may have seeped between forming panels during concrete pour of the foundation.  Simply chip off the excess concrete with a brick chisel or concrete chisel to ensure the panels sit flat on the foundation wall (Figure 1).

Note: If necessary, an air barrier consisting of either TYVEC or TYPAR might be required to be placed between the wall and the insulation panel. Check with local building codes to determine if this is necessary for the insulation for basement walls with NUDURA


1. Install NUDURA Insulation Technology

Starting at the corner of the foundation wall, remove the shoulder edge to allow proper spacing so Panel B can be positioned. Removing the shoulder edge from the top and bottom of the panel may be necessary depending on ceiling heights for insulation of basement walls.

Panel B will have to have the shoulder (Figure 3) edge removed to be placed against panel A leaving a ½” RetroFit Intstallation Figure 3gap. This installation step for insulation of basement walls will have to be done at every inside corner to ensure the proper attachment of Gypsum or drywall can be made.

Each corner will then have to be filled with NUDURA Low Expansion Spray Foam to create a thermal barrier to ensure insulation of basement walls is sealed.
RetroFit Installation Figure 5
Attach NUDURA Insulation Technology using a mechanical fastener such as a concrete screw [5” for 2 5/8 (67mm) or 3 1/2” (89mm)]. To make fastening the panels for insulation of basement walls easier, place your first fastener into the middle of the panel on the fastening strip to hold it in place (as shown in Figure 5). Fasteners are to be placed vertically every 2 feet on the fastening strip, on center. Once the Panel is secure, place the next panel in place using the shiplap system.

Note: Place the shiplap edge in an open condition for easy installation (see Figure 6 & 7).

Note: For insulation of basement walls less than 8’ high, notch the panel to fit around the floor joist and seal with NUDURA Low Expansion Spray Foam - Wall Height Reference Chart.


For installation around windows, cut and remove the appropriate amount of panel needed, then fasten (Figure 8). When installing panels around windows, remember to leave a gap between the cut panel and the window frame. Once installation is complete, fill the gap between the window and the insulation (if required) with NUDURA’s Low Expansion Spray Foam to create a thermal barrier around the window.


In some instances it may be necessary to install a piece of aluminum or sheet metal on outside corners for corner bead installation. Consult your local building supply chain for material that is pre-folded to 90° to fit the necessary size requirements for insulation for basement walls. To install, simply cut to measure, and   install at the same time as drywall installation. Attach the material on the outside corner, then place drywall over top and fasten drywall to the wood fastening strips.

2. Electrical Installation

A variety of methods can be used to install electrical wiring: hot knife, router or fine bladed knife. Never cut RetroFit Installation Figure 10through the wood fastening strip. Electrical is to be placed behind the fastening strip by removing the EPS. Install electrical wiring by first cutting a  channel (1¼” min.) into the panel.

Electrical boxes are easily fastened to the wood fastening strip buy using the appropriate mechanical fastening method (shown in Figure 10). For electrical installation please refer to local and national building codes. Electrical wiring should always be installed by a licensed electrical contractor.

3. Drywall Installation

Install ½” (12 mm) drywall and connect to the wood fastening strip using a 1¼” (32 mm) drywall screw. Fastening strips are placed 16” (400 mm) on center for easy installation (Figure 11).

Note: For all types of corner bead installation, consult with your local building supply chain or to the manufacturers suggested installation guidelines.

  North America 866-468-6299 International +1 705-726-9499