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Fanfold Insulation

Fanfold siding underlayments have been core to our business since 1982! Multiple products are available and are designed to lay flat, giving siding being installed over them a smooth, even finish. They retain their insulating properties over time.

All products have very low moisture absorption, are not food sources for mold, and are not subject to moisture-related damage and deterioration. Fantastic products for re-siding and retrofit.

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Premium choice underlayment ¼” thick XPS; best facers, cut-and-fold hinges

GreenGuard XP14 Fanfold Underlayment

Premium choice underlayment ¼” thick XPS; best facers, cut-and-fold hinges

Economical fanfold XPS 0.2" thick with reflective facer on one side

GreenGuard FQ250 Fanfold Underlayment

Economical fanfold XPS 0.2" thick with reflective facer on one side

Premium level ¼” XPS fanfold with reflective facer and cut-and-fold hinges

GreenGuard XFP14 Fanfold Underlayment

Premium level ¼” XPS fanfold with reflective facer and cut-and-fold hinges

Premium level ⅜” XPS fanfold with reflective facer and cut-and-fold hinges

GreenGuard XFP38 Fanfold Underlayment

Premium level ⅜” XPS fanfold with reflective facer and cut-and-fold hinges

Economical fanfold XPS 0.3" thick with reflective facer on one side

GreenGuard FQ350 Fanfold Underlayment

Economical fanfold XPS 0.3" thick with reflective facer on one side

Premium level ⅜” XPS fanfold with our best facers, cut-and-fold hinges

GreenGuard XP38 Fanfold Underlayment

Premium level ⅜” XPS fanfold with our best facers, cut-and-fold hinges

Performance level underlayment ¼” thick XPS with crease-fold hinges

GreenGuard P1450 Fanfold Underlayment

Performance level underlayment ¼” thick XPS with crease-fold hinges

Economical fanfold underlayment XPS 0.2" thick with crease-fold hinges

GreenGuard Q250 Fanfold Underlayment

Economical fanfold underlayment XPS 0.2" thick with crease-fold hinges

Economical fanfold underlayment XPS 0.3" thick with crease-fold hinges

GreenGuard Q350 Fanfold Underlayment

Economical fanfold underlayment XPS 0.3" thick with crease-fold hinges