XPS is an ideal material for thermal insulation in reefers, truck bodies ,and constructions. Last time we introduced it’s property and process. Today, let’s move on the installation of XPS foam.

XPS Foam Installation Guidelines

As more sheathing insulating options are made available, builders are constantly seeking easier and better installation methods. While traditionally following ongoing trends in residential building systems installation, changes in local codes and new product introductions challenge builders to erect better homes that offer more resistance to

moisture and increased energy efficiency.

Properly installed XPS foam insulating sheathing can provide excellent moisture and insulating properties. As mentioned, extruded polystyrene plastic products are light, versatile, and easily installed on residential walls as illustrated in the following step-by-step guide:

The first step is to mark the extruded polystyrene foam insulation boards by dragging the hook of a measuring tape along the surface of the plastic insulation board, while holding the other end of the tape at the desired measurement. This creates a small mark to follow when cutting.

The plastic insulation board should then be placed on a flat, sturdy surface for cutting ease and safety. A pair of sawhorses is usually sufficient for waist-high work. Following the mark left by the tape edge, a deep impression should be made with a knife held low against the board (without cutting through).Once the entire measured line has been scored, the piece is simply snapped over the edge of the work surface. It is best to use a utility knife and straight edge to trim the XPS foam insulation board to conform to irregular wall angles, projections, or wall surfaces less than board width or height.

Code-acceptable corner bracing (e.g. diagonal metal strapping, let-in wood, or wood structural sheathing) is then installed. If wood sheathing is used as a structural component, the building can be covered with extruded polystyrene foam insulation boards to provide for full wall insulation.

XPS foam insulation boards that are 1.2 m (4 ft) wide should be installed vertically with long joints butted tightly together and bearing directly on the framing members. Horizontal joints should be minimized between boards, unless joints are positioned directly over a horizontal framing member. Taping the extruded polystyrene foam insulation board joints seals them against air infiltration for improved energy efficiency.

It is preferable to secure XPS foam insulation boards with 25.4-mm (1-in.) head plastic cap nails long enough to penetrate framing measuring at least 19 mm (0.75 in.). Another option is to use 9.5-mm (0.375-in.) head-galvanized roofing nails long enough to penetrate framing a minimum of 19 mm. Additionally 25.4-mm crown, 16-gauge wire staples long enough to penetrate framing a minimum of 12.7 mm (0.5 in.) can also be used. Nail heads or staples should not be over-driven.6. The field of the extruded polystyrene foam board is then secured 406 mm (16 in.) on-center (oc) and around the perimeter 305-mm (12-in.) oc,or as required by the building code authority having jurisdiction.

In stick-built construction, one should consider using 1.2 x 2.7-m (4 x 9-ft) XPS foam insulation boards to effectively cover the sill plates, floor/ceiling junctures, bandbox, and headers in one application with fewer horizontal joints. Brick, wood, hardboard, aluminum, or vinyl sidings are fastened to the wood frame construction through the insulation in accordance with the siding manufacturer’s instructions. Shakes or shingles can also be applied by installing furring strips or a plywood nailer base over the insulation and attaching the shakes or shingles. The manufacturer should be consulted on the most appropriate methods.