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Insulfoam R-Gard 1/2 in. R-Tech Fanfold Insulation, White, 2 Square Bundle
Regular price $88.35Orders start at $399 — combine any items to reach the minimum. Learn more
Insulfoam R-Gard 1/2 in. R-Tech Fanfold Insulation, White, 2 Square Bundle
This is Insulfoam R-Gard fanfold insulation, 1/2 in. R-Tech rigid foam board in white, supplied as a bundle covering 2 squares (200 sq ft). The interlocking fanfold panels provide a continuous insulation layer under siding or cladding. Pair it behind vinyl, steel or other exterior siding systems.
Key Features:
- Fanfold format: Interlocking fanfold panels unfold quickly over large wall areas.
- Continuous insulation: Creates a continuous 1/2 in. insulation layer under exterior cladding.
- 2 square bundle: Each bundle covers 2 squares, or 200 square feet, of wall area.
- White finish: Supplied in white for use behind most siding types.
- Rigid foam: Polystyrene rigid insulation resists moisture and holds its shape.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Insulfoam |
| Sell unit | 1 bundle, 2 squares (200 sq ft) |
| Product line | Insulfoam R-Gard / R-Tech fanfold |
| Material | Polystyrene |
| Color / finish | White |
| Thickness | 1/2 in. |
| Coverage per unit | 2 squares (200 sq ft) per bundle |
| Intended use | Continuous fanfold insulation under exterior siding |
Coverage & How Much You Need:
One bundle covers 2 squares, about 200 square feet of wall. Calculate the net wall area after openings, add a small allowance for laps, and divide by 200 sq ft per bundle to size the order.
Fit and Compatibility:
Designed as a backer and insulation layer under exterior siding, including vinyl and metal cladding, with the fanfold edges interlocking to close gaps. Siding, starter strips and fasteners are sold separately; confirm fastening pattern with the siding manufacturer.
Frequently Asked Questions (FAQ):
Q: What is included with one order?
A: One bundle of Insulfoam 1/2 in. R-Tech fanfold insulation covering 2 squares (200 sq ft), in white.
Q: How thick is the board?
A: The fanfold board is 1/2 in. thick.
Q: How many bundles do I need?
A: Divide the net wall area, including a small waste allowance, by 200 square feet per bundle.
Q: Where is it used?
A: It is installed as a continuous insulation layer behind exterior siding on walls.
Q: How are the boards joined?
A: Fanfold panels have interlocking edges that unfold and lock together across the wall, minimizing gaps between boards.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Fanfold underlayment is the standard choice behind re-siding jobs because it goes up fast, bridges old siding imperfections and adds a modest continuous R-value. Keep the fanfold flat and lapped shingle-style so the new siding sits even, and do not leave crushed or torn panels behind the new cladding. Choose a thicker rigid board instead when a specified continuous R-value must be met.
Follow local building code requirements for continuous insulation and vapor management in your climate zone, and keep polystyrene away from open flame during storage and installation.
Order the Insulfoam R-Gard 1/2 in. fanfold insulation bundle to back your next siding job.
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