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R400 Rubber Application for Conventional Gravel Roof
- Inspect the entire roof surface. Excess gravel should be removed and all blisters should be cut open and allowed to dry. Remove all debris, trash, etc.
- Apply the Cement Catalyst/Portland Cement mixture to the entire roof surface. The mixture must be made liquid enough to flow through the gravel. Apply the slurry until the gravel is covered or until a “level” surface is obtained. The slurry system can be installed with a soft pushbroom or squeegee. The slurry should be applied in two coats, allowing the first coat to dry before applying the second.
- After the slurry has cured for 3 days, apply the Pro Bond 200 to the entire surface. This sealer usually dries in less than 1 hour.
- Apply the R400 Rubber to the entire surface in 2 coats of 11 mils each. Two complete coats should have a thickness of 22 dry mils.
- Anywhere where water ponds or lays , Polyester Membrane must be used. First put a coat of R400 down, then immediatly roll a section of fabric out, then immediatly roll another coat of R400 over the fabric, then allow to dry. After drying you need to apply 2 additional coats of R400 Rubber over the fabric, or until no fiber strands are visible.
- No top coat is required with R400 Rubber. Due to the non chalking surface, there will be some dirt pickup.
Installation Notes
- On a gravel roof surface, one 5 gallon bucket of R400 Rubber will cover 200 square feet of gravel roof, which will result in 22 dry mils of waterproofing.
- On a gravel roof surface using Polyester Membrane, one 5 gallon bucket of R400 Rubber will cover 90-100 square feet of gravel roof. It is recommended that where the ponding water lays, R400 Rubber must be embedded with the Polyester Membrane.
- If spraying the R400 Rubber, it must be chased with a roller
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