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RPI Water Cut Off Mastic 10.3 oz Tube, One-Part Butyl Compression Sealant, Gray
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RPI Water Cut Off Mastic 10.3 oz Tube, One-Part Butyl Compression Sealant, Gray
RPI Water Cut Off Mastic is a weather-resistant, one-part butyl sealant supplied in a 10.3 oz gray tube and designed to act as a compression gasket. It is used with pipe boots, termination bars and drain clamping rings per RPI specifications. It is not designed to be used as an exposed caulk.
Key Features:
- Butyl based: A one-part butyl-based sealant formulated as a weather-resistant compression gasket.
- Compression sealing: Functions as a compression sealant with pipe boots, termination bars, drain clamping rings and other details required by RPI specifications.
- Weather resistant: Formulated to resist weather exposure in concealed roofing details.
- Trade-sized tube: Comes in a 10.3 oz tube suited to cartridge application on roofing details.
- Not exposed caulk: Cut-off mastic is not designed to be used as an exposed caulk.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | RPI |
| Sell unit | 1 tube, 10.3 oz |
| Product line | RPI roof system accessories |
| Available colors | Gray |
| Available sizes | 10.3 oz tube |
| Material | One-part butyl-based sealant |
| Finish / texture | Gray mastic |
| Intended use | Compression gasket sealant for pipe boots, termination bars, drain clamping rings |
| Limitations | Not designed for use as an exposed caulk |
Fit and Compatibility:
Intended for use with RPI-specified roof system details such as pipe boots, termination bars and drain clamping rings. RPI Night Seal is the companion product for sealing temporary tie-ins between new roof covers and existing roof systems.
Frequently Asked Questions (FAQ):
Q: What is included?
A: One 10.3 oz tube of gray RPI Water Cut Off Mastic, sold per tube.
Q: Where is it used?
A: As a compression sealant with pipe boots, termination bars, drain clamping rings and other details required by RPI specifications.
Q: Can I leave it exposed on the roof?
A: No, the manufacturer states cut-off mastic is not designed to be used as an exposed caulk; keep it in compression within the detail.
Q: What type of sealant is it?
A: It is a weather-resistant, one-part butyl-based sealant designed to work as a compression gasket.
Q: What should I use for temporary tie-ins?
A: RPI Night Seal is designed as a quick, reliable sealer at temporary tie-in locations between new and existing roof systems.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Use this butyl mastic only in compressed, concealed details such as under termination bars or around clamping rings, and choose a face-seal product where a fillet must remain exposed. Apply to clean, dry substrates and bed the detail firmly so the butyl can function as a gasket. Keep tubes sealed until use so the material stays workable.
Review the product safety information before use and apply in well-ventilated conditions with appropriate personal protection.
Stock RPI Water Cut Off Mastic for dependable compression sealing on pipe boots, termination bars and drain details.
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