Blue Ridge FiberBoard Structodek HD 1/2 in. x 4 ft. x 4 ft. Primed Red Coated Fiberboard Roof Insulation, 2 Sides

Structodek HD is a 1/2 in. x 4 ft. x 4 ft. high-density fiberboard roof insulation board with a proprietary non-asphaltic primed red coating on two sides. The coating delivers superior adhesion with modern single-ply membranes and low-VOC, water-based and foam adhesives. Sold per piece; four pieces per square.

Key Features:

• Primed red coating: Non-asphaltic primed red coating provides superior adhesion without excess adhesive absorption.
• Membrane compatible: Compatible with PVC, TPO, EPDM and CSPE single-ply membranes without membrane degradation.
• Adhesive versatility: Works with traditional, low-VOC, water-based and many foam adhesives.
• Moisture protection: Waxes added early in manufacturing give superior core and edge moisture resistance.
• FM Approved: FM Approved Class 1 per Standard 4450/4470 and UL Classified to UL 790.
• High density: Structodek HD meets ASTM C 208 Type II, Grade 1 and Grade 2 and CAN/ULC-S706-09.

Specifications Table:

Coverage & How Much You Need:

Each 4 ft. x 4 ft. board covers 16 sq ft, so one square (100 sq ft) of roof area takes roughly seven boards with appropriate waste allowance; the listed UOM confirms 4 pieces per square reference. Allow for cutting and laps when sizing the job.

Fit and Compatibility:

Designed as an insulation/recover board under single-ply membranes (PVC, TPO, EPDM, CSPE) and compatible with traditional, low-VOC, water-based and many foam adhesives. Membrane, adhesives and fasteners/plates are sold separately.

Frequently Asked Questions (FAQ):

Q: What size is each board?
A: 1/2 in. thick, 4 ft. x 4 ft., coated two sides with primed red coating.

Q: How many boards per square?
A: The listing UOM indicates 4 pieces per square; check your layout for cut waste.

Q: Which membranes is it compatible with?
A: PVC, TPO, EPDM and CSPE single-ply membranes, plus traditional systems.

Q: Which adhesives work with it?
A: Traditional, low-VOC, water-based and many foam adhesives, with superior adhesion and no excess absorption.

Q: What approvals does it carry?
A: UL 790 Classified, FM Approved Class 1 (4450/4470), Miami-Dade NOA 18-0523.03, FBC FL #13792.1 and CCMC #13186-L, among others.

Q: Is this painted?
A: No, the primed red coating is a factory bonding surface, not a finished color coat.

Expert Verdict — Reviewed by the SuperArbor Pro Desk

Structodek HD is the right recover board when you need an asphalt-free substrate under single-ply membranes, since asphalt emulsion boards can degrade PVC and TPO over time. Install over a sound deck per the membrane system's requirements, staggering joints and fastening or adhering per FM approval details. Order adhesive and membrane from the same system family for full warranty compliance.

Handle boards with gloves and eye protection; cutting fiberboard creates dust, so cut in ventilated areas.

Order Structodek HD primed red fiberboard insulation for your next single-ply recover.