R Guard Porous Prep Water-Based Sealer - Pallet of 96 Units - 1 Gallon Each

PorousPrep — Water-Based Edge Sealer for Raw Gypsum Board

PorousPrep is a water-based sealer engineered to seal the dry, cut edges of gypsum wall boards exposed in rough openings for windows and doors. Designed for contractors working with continuous air barrier systems, it prepares porous gypsum edges so that subsequent applications of Joint & Seam Filler or FastFlash go on fast and efficiently. Its formulation is solvent-free, VOC-compliant, and water-cleanup ready, making it a practical fit for job sites with strict environmental or indoor air quality requirements. PorousPrep is manufactured by PROSOCO and is part of the R-Guard building envelope product family.

Unlike solvent-based alternatives, PorousPrep carries no solvent odor and cleans up with water, reducing crew exposure and simplifying disposal. Its glue-like viscosity distinguishes it from thinner sealers by resisting rundown on vertical surfaces and minimizing the risk of spills during application.

Key Features & Benefits

Glue-Like Viscosity for Controlled Application

PorousPrep's thicker, glue-like consistency allows it to stay where it's applied on dry, cut gypsum edges without running down the face of the board. This reduces material waste and keeps the work area cleaner, which matters on busy framing and rough-opening crews.

Fast Dry Time

PorousPrep typically dries in 30 to 60 minutes when applied to dry surfaces. This allows crews to follow up with Joint & Seam Filler or FastFlash without lengthy delays, keeping the air barrier installation on schedule.

No Solvent Odor

The water-based, solvent-free formula produces no solvent odor during application. This is especially valuable in enclosed or partially enclosed structures where ventilation is limited and crew comfort or indoor air quality requirements apply.

Water Cleanup

Tools and equipment clean up with water, eliminating the need for solvent-based cleanup products. This simplifies jobsite cleanup and reduces the cost and handling burden associated with flammable solvents.

VOC Compliant Nationwide

PorousPrep is compliant with all national, state, and district AIM VOC regulations, including CARB 2007 SCM and SCAQMD rules. Contractors working in the most restrictive regulatory jurisdictions can specify and use this product without substitution.

Living Building Challenge Red List Free

PorousPrep has been reviewed by PROSOCO and verified to contain no intentionally added chemicals present on the Living Building Challenge Red List. It also conforms to LBC 2.1/2.2/3.0/3.1/4.0 Materials Petal requirements, supporting project submissions for LBC, LEED 2009, and LEEDv4 certification.

Common Applications

Sealing Raw Gypsum Board Edges at Window Rough Openings

PorousPrep is applied to dry, cut gypsum edges exposed at window rough openings, sealing the porous surface so that Joint & Seam Filler or FastFlash can bond effectively without being absorbed into the substrate.

Sealing Raw Gypsum Board Edges at Door Rough Openings

Cut gypsum edges at door rough openings present the same absorption challenge and are a primary use case for PorousPrep prior to air barrier membrane application.

Preparation for Joint & Seam Filler Application

PorousPrep is used as a conditioning step before applying R-Guard Joint & Seam Filler to ensure adhesion is fast and efficient on otherwise highly absorbent gypsum cut edges.

Preparation for FastFlash Application

When FastFlash is the selected liquid flashing membrane, PorousPrep seals the gypsum edge first, ensuring the FastFlash goes on smoothly and performs as intended at transitions and rough openings.

Component in a Continuous Building-Wide Air Barrier System

PorousPrep can be used as part of a complete, building-wide R-Guard air barrier assembly, or to complement conventional waterproofing or air barrier components at gypsum board terminations.

Compatible Materials

• Dry, cut edges of gypsum wall board (exposed at rough openings)
• R-Guard Joint & Seam Filler (applied over PorousPrep-sealed edges)
• R-Guard FastFlash (applied over PorousPrep-sealed edges)

Product Documents

• Product Data Sheet
• Safety Data Sheet
• Safety Data Sheet (Spanish)
• SDS Canadian French
• VOC Compliance
• LEED Verification Letter
• SCS Certification
• LBC Red List Conformant Product Summary

Technical Specifications

Frequently Asked Questions

Q: What surfaces is PorousPrep designed for?
A: PorousPrep is specifically designed for dry, cut edges of gypsum wall boards exposed at rough openings for windows and doors. It is not described for use on other substrates in the available source material.

Q: Does PorousPrep need to dry before applying Joint & Seam Filler or FastFlash?
A: Yes. PorousPrep typically dries in 30 to 60 minutes when applied to dry surfaces. Allow it to dry before applying subsequent air barrier products like Joint & Seam Filler or FastFlash.

Q: Is PorousPrep compliant in California and other high-restriction VOC jurisdictions?
A: Yes. PorousPrep is compliant with all national, state, and district AIM VOC regulations, including the CARB 2007 SCM and SCAQMD rules, making it usable in the most restrictive regulatory environments in the U.S.

Q: Can PorousPrep be used on projects pursuing LEED or Living Building Challenge certification?
A: Yes. PorousPrep has been verified compliant with LEED 2009 and LEEDv4 referenced regulations and has been confirmed Red List Free under the Living Building Challenge Materials Petal requirements. Supporting documentation including a LEED Verification Letter and LBC Red List Conformant Product Summary are available for download.

Q: Is PorousPrep only for use as part of a full R-Guard system?
A: No. While PorousPrep is designed to work within the R-Guard air barrier system, it can also be used to complement conventional waterproofing or air barrier components from other systems at gypsum board edge terminations.