Plasti Grip ci prong washer with pink XPS on wood
Rigid Insulation Application

Fast and effective rigid insulation attachment

SPAX® Plast-Grip® ci Prong washers can be used to attach insulation to all substrates with the correct fastener.



Importance of Rigid Insulation

As energy codes across the US become more stringent, and energy costs continue to increase, insulating homes and buildings with continuous rigid insulation is becoming more popular, or in some cases even code mandated.

Rigid insulation is a great way to boost your structures R-Value whether attaching to foundation or to studs when building a new structure.

Fasteners for Rigid Insulation

Rigid insulation comes in varying thicknesses and may be attached to a variety of substrates depending on the building make-up.

It's important that the right fasteners are used to ensure that the insulation is secure and is being attached with thermal-efficiency in mind. SPAX® Fasteners along with the Plasti-Grip® ci prong washers help you achieve both of these when attaching rigid insulation.

Plasti-Grip® ci prong washers offer a large 1.75" diameter washer that is both thermally efficient and will provide maximum holding power to prevent insulation sagging and wind-blow off during the course of construction.

SPAX® #6-#10 Multi-Material fasteners can be used with these washers in a variety of substrate applications.

*Please note, if installing into concrete/CMU, fastener holes will need to be pre-drilled according to manufacturers specifications. We recommend use of flat head screws for flush mounting of washer.

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Find the right screw or fastener for your next job with the largest variety of diameters, lengths and head styles in the industry.

Related Products


Ensure proper attachment of rigid insulation using Plasti-Grip® ci prong washers with SPAX® multi-material fasteners.

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