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CertainTeed DiamondDeck Synthetic Roofing Underlayment, 10 Square Roll, Cool Gray
Regular price $217.00Orders start at $399 — combine any items to reach the minimum. Learn more
CertainTeed DiamondDeck Synthetic Roofing Underlayment, 10 Square Roll, Cool Gray
CertainTeed DiamondDeck is a synthetic steep-slope roofing underlayment supplied as a single roll covering 10 squares of roof area. The Cool Gray surfacing provides a clean secondary water-shedding layer beneath shingles, shakes or metal panels. Order by the roll for full underlayment coverage.
Key Features:
- 10 squares per roll: One roll covers 10 squares of roof area, so fewer rolls are needed per job than many traditional felts.
- Synthetic construction: DiamondDeck is a synthetic underlayment designed for steep-slope roofing applications.
- Cool gray surfacing: The roll is surfaced in Cool Gray, a neutral tone that stays low-visibility under finished roofing.
- Steep-slope rated: Manufactured by CertainTeed for use as steep-slope roofing underlayment.
- Roll sell unit: Sold as one roll per order unit for straightforward job takeoffs.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | CertainTeed |
| Sell unit | 1 roll, 10 squares |
| Product line | CertainTeed DiamondDeck Synthetic Underlayment |
| Available colors | Cool Gray |
| Available sizes | 10 square per roll |
| Material | Synthetic underlayment |
| Color / finish | Cool Gray |
| Coverage per unit | 10 squares per roll |
| Intended use | Steep-slope roofing underlayment |
| Category | Roofing Materials > Roof Membranes, Sheets, Roll Roofing & Underlayments > Steep Slope Roofing Underlayment |
Coverage & How Much You Need:
Each roll covers 10 squares (1,000 sq ft) of roof area. Divide total roof square footage by 1,000 to estimate rolls, and allow extra for eaves, rakes and laps depending on your course overlap.
Fit and Compatibility:
DiamondDeck installs beneath finished steep-slope roof coverings such as asphalt shingles and is a natural match with CertainTeed shingle lines. Starter strips, hip and ridge products and fasteners are sold separately; consult the manufacturer's installation instructions for deck and fastening requirements.
Frequently Asked Questions (FAQ):
Q: What is included with one order?
A: One roll of CertainTeed DiamondDeck synthetic underlayment in Cool Gray, covering 10 squares.
Q: How many rolls do I need?
A: Divide your roof area in squares by 10; add a roll of margin for laps, valleys and starter courses.
Q: Can it be exposed to weather?
A: It is intended as an underlayment beneath finished roofing; check the manufacturer's instructions for permitted exposure time before the roof covering is installed.
Q: What roofing materials can it be used under?
A: It is designed for steep-slope roofing underlayment use, such as beneath asphalt shingle roofing.
Q: Is it a wet-felt replacement?
A: It is a synthetic underlayment rather than asphalt-saturated felt; follow CertainTeed's fastening and overlap requirements for the deck type.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Synthetic underlayment like DiamondDeck is chosen for its high coverage per roll and lighter handling than #30 felt. Plan courses so horizontal laps shed water correctly, and confirm fastener pattern for your deck type. Pair with matching CertainTeed starter and hip-and-ridge products for a complete manufacturer-matched system.
Underlayment surfaces can be slippery, especially when wet or frosted; wear fall protection and slip-resistant footwear while installing.
Order CertainTeed DiamondDeck Synthetic Underlayment by the roll for your next steep-slope roofing job.
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