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

GreenGuard P1450 Fanfold Underlayment

Performance level underlayment ¼” thick XPS with crease-fold hinges
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 0.2" thick with reflective facer on one side

GreenGuard FQ250 Fanfold Underlayment

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