Rubber Patch ®

Rubber Patch is PermaDri’s trowel-grade product. Rubber Patch® is a companion product for other PermaDri coatings as its thicker consistency makes it ideal for patching and preparing surfaces. Rubber Patch®can be used to fill voids larger than 1/8 inch prior to coating surfaces with other PermaDri products. Rubber Patch® easily adheres to virtually any surface and it typically cures within 24-48 hours (depending on application thickness, temperature, and relative humidity). Like all PermaDri products, Rubber Patch® is environmentally-friendly and contains no VOCs.

Rubber Patch® is a modified elastomeric asphalt emulsion specifically formulated for application by trowel. Rubber Patch® is a cold applied, single component product that yields a membrane with excellent strength, elasticity and adhesion. Rubber Patch® is an environmentally friendly waterproofing product that can be applied indoors and outdoors with conventional protective equipment.*

Each coating is applied cold, so protective equipment is not required during application. PermaDri products contain no noxious odors or VOCs – making all coatings environmentally safe. You can even use them in fish ponds.

PermaDri products do not get brittle over time, do not deteriorate with prolonged exposure to water, and are impervious to many chemicals. Our coatings have tremendous elasticity and recovery; they can handle the expansion and contraction of buildings. PermaDri coatings will not sustain flame and are UV resistant. These features make PermaDri products perfect for waterproofing and corrosion protection applications.

Roof Tax Advantages

In most cases, roof maintenance coatings are treated as full write-offs  by the IRS versus re-roofing which is in the category of a capital improvement and thus subject to write offs over a 15 year period.

Trowel Grade
  • Specific gravity (liquid) g/cm3: Approx. 1:0
  • Odor: None
  • VOC: Contains no solvents
  • Color: Brown to black
  • % solids (wt): 63-68
  • Viscosity, Brookfield, sp. #5, 20 rpm: 20,000-30,000
  • pH: 10-12
Performance (cured membrane)
  • Color: Black
  • Specific gravity g/cm3: Approximately 1.0
  • Chemical resistance: Resistant to most inorganic solutions. Not recommended for gasoline or other petroleum products. Consult Chemical Resistance chart for further information.
  • Tensile strength ASTM 0412, psi: 50
  • Elongation, %: 1000
  • Accelerated weathering, ASTM G 155,0 412: Passed
  • Tensile strength: Passed (>90% original value
  • Hardness, Durometer Type 00: 85-90
Application & Limitations

Rubber Patch® is a water-based, environmentally safe alternative to conventional hot-applied, solvent based and sheet membrane waterproofing systems. Since Rubber Patch® cures by evaporation, a minimum application temperature of min. 40ºF (4.5ºC) is required. Apply in thin coats. The product cures within 24-48 hours at 70ºF (21ºC) and 50% relative humidity, at a thickness of 40 mils (1mm).

For best results, surfaces must be dry and free of dirt, debris, oil or grease. Application is not recommended if rain is imminent, or in high humidity environments.

Rubber Patch® is applied between 20-30 ft²/gal (0.3-0.7 m²/litre) to produce a 40-60 mil (1-3 mm) protective membrane. Rubber Patch® dries to the touch within minutes at 70ºF (21ºC). Curing time will vary depending on temperature and relative humidity.


*Rubber Patch® is mildly alkaline. When applying this product observe appropriate safety precautions, wear gloves, eye protection and other suitable protective equipment. For further information please consult the product MSDS.

Rubber Patch® should not be applied when the ambient temperature is below 40ºF (4.5ºC). The uncured membrane may be damaged if frozen. Some surface base coats, such as coal tar are unsuitable for use with Rubber Patch.®


For industrial use only. Keep out of reach of children. Avoid storage below 40ºF (4.5ºC). Please consult the MSDS before using Rubber Patch.®

MSDS/Factsheet: Download here