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Features You Can Count On

Kingspan GreenGuard Raindrop 3D Building Wrap

Advanced Air/water Barrier House Wrap

As an air barrier material, it has demonstrated water holdout capabilities in industry-recognized water resistance tests.

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  2. Fanfold Insulation
  3. GreenGuard FQ350 Fanfold Underlayment

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

GreenGuard Q250 Fanfold Underlayment

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

GreenGuard Q350 Fanfold Underlayment

Economical fanfold underlayment XPS 0.3" thick with crease-fold hinges
Kingspan GreenGuard FQ350 fanfold underlayment on a transparent background

GreenGuard FQ350 Fanfold Underlayment

When every penny counts, you can rely on the performance of one of our most economical fanfold siding underlayments. The 0.3" FQ350 is made of extruded polystyrene foam (XPS). Designed to be used as a “leveling board”, it adds insulation and moisture protection during installation of new vinyl siding over old siding. It is configured in fanfolded bundles 4’ x 48’. It comes with crease-fold hinges and a reflective facer on one side for added energy efficiency.

Product Highlights

  • Reflective facer on one side for added energy efficiency

  • Lightweight, durable... cuts clean and easy

  • Perforated to allow moisture vapor to escape

  • Provides a smooth, level nailing surface for new siding