Westlake Royal™ Ply 40 Underlayment/Base Sheet
Westlake Royal Ply 40 is an SBS-modified fiberglass reinforced underlayment/base sheet for tile, shingle, or shake. SBS-modified asphalt minimizes wrinkling & buckling associated with non-modified membranes.
About Ply 40 Underlayment/Base Sheet
Features
- Durable Protection – All Seasons, Easy Installation
- 180 Days Uncovered Exposure
- 10 Year Limited Manufacturer’s Warranty for one layer
- 20 Year Limited Manufacturer’s Warranty for two layers
Specifications
- Roll Size: 39 3/8” x 65’ 10” (216 sq ft)
- Roll Weight: 75 lbs (nominal)
- Coverage: Net 2 Squares
- Thickness: 55 mils (nominal)
- Rolls per pallet: 24 Rolls
- Pallet weight: 1,880 lbs (nominal)
Handling & Storage
- Rolls are to be stored in standing position only
- Store in a clean, dry, cool area
- Do not store directly in sunlight without proper protection
- Protect membranes from exposure to rain, snow, or ice
- Westlake Royal Ply 40 may be stored 2 pallets high provided a slip sheet of 3/8” minimum thickness of plywood is provided between pallets
Part Numbers
- 92499 – 2 Square Roll
- 92498 – Drop Ship: 576 Rolls/Truck
Certifications & Approvals
- ASTM-D4601
- D6757
- Meets the physical requirements of ASTM-D226
- D4869
Steep Roof Application
Secure underlayment with 1” head nails
Resource Center
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FAQs
What are the specifications of Westlake Royal Ply 40 underlayment?
Specifications can be found on the product brochure on our website.
What installation techniques are recommended for Ply 40 in cold climates?
A best practice in cold climates is to allow ORG 40 to warm up in the sun prior to installation.
Are there any substrate requirements for installing Ply 40?
A clean, dry, smooth roof deck that is properly fastened to the framing is necessary to achieve a proper, long-lasting installation.
Is Ply 40 suitable for use under asphalt shingles?
Yes, Westlake Ply 40 may be used under asphalt shingles.
What is the exposure lmiit of Ply 40?
Ply 40 may be exposed up 180 days prior to installation of the roof covering.
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