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GreenGuard XP38 Fanfold Insulation

Best Choice Underlayment ⅜” Thick XPS

Top-of-the-line perforated facers on both sides for use in replacement siding operations.

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Kennesaw State University Prebuild 4:3

Kennesaw State University

Kingspan Insulation plays a key role in KSU's impressive new student center

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  3. GreenGuard XP38 Fanfold Underlayment
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
Premium choice underlayment ¼” thick XPS; best facers, cut-and-fold hinges

GreenGuard XFP38 Fanfold Underlayment

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

GreenGuard XP14 Fanfold Underlayment

Premium choice underlayment ¼” thick XPS; best facers, cut-and-fold hinges
Kingspan GreenGuard XP38 Fanfold Underlayment on a transparent background.

GreenGuard XP38 Fanfold Underlayment

Kingspan's premium choice ⅜” (0.375") thick closed-cell extruded polystyrene (XPS) fanfold underlayment with our best-perforated facers on both sides for use in replacement siding operations; is designed to be used as a “leveling board”, adding insulation and moisture protection in installation of new vinyl siding over old siding. It is configured in fanfolded bundles 4’ x 50’ with cut-n-fold hinges which improves its ability to lay flat. It is lightweight, easy to cut, and install.

Product Highlights

  • Kingspan's Top-of-the-line facers

  • Lay flat cut-and-fold hinges

  • Perforated to allow moisture vapor to escape