Karnak #298 Alumin-R is a single component, SBS rubber modified asphalt, and is specially formulated with aluminum pigment to be used as a reflective elastomeric coating with modified bitumen membranes, B.U.R., properly sloped residential concrete roofs and primed metal surfaces. The strength and elastomeric qualities of Karnak #298 Alumin-R combined with its reflective properties, enhance the coating's ability to resist movement. Karnak #298 Alumin-R provides the membrane with good weathering and elongation properties and reduces roof surface temperatures.
- Easy to apply.
- 24 hour cure.
- Tough, flexible elastic, rubber-like film.
- Excellent adhesion over clean asphalt surfaces.
- Excellent water and water vapor resistance.
- Excellent weather resistance.
- Good resistance to salts and alkalies.
- Aluminum reflectant characteristics.
Karnak #298 Alumin-R is recommended as a coating for on modified bitumen membranes, BUR, metal and mobile home roofs.
All surfaces to be coated with Karnak #298 Alumin-R must be clean, dry, free from oil, grease, and loose debris. ft. per gallon prior to the coating application. New asphalt roof surfaces may be coated with Karnak #298 Alumin-R five days after their installation.
Modified bitumen membranes should be coated immediately after the membrane has been laid into place. Metal roofs should be brushed or sandblasted with a pressure washer to remove rust and loose flaking prior to the application of Karnak #298 Alumin-R.
Karnak #298 Alumin-R should be mechanically mixed for several minutes before application.
Badly weathered or alligatored asphalt surfaces should be primed with Karnak 100AF Non-Fibered Emulsion or 220AF Fibered Emulsion prior to coating with 298AF Alumin-R. Allow emulsion to cure a minimum of 3-5 days before application of aluminum coating.
Karnak #298 Alumin-R can be applied by brush, roller or spray equipment. If spray equipment is utilized, use a standard heavy duty spray pump. Equipment manufacturer should be consulted for more complete information.
Recommended rate of 1.5 to 2 gallons per 100 sq. ft. in one application.
Tools may be cleaned with mineral spirits or similar solvent.
- Weight per Gallon: 8.5 lbs.
- Solids by Weight: 47%
- Color: Silver
- Permeability: 0.15 mg.per sq. cm.
- Cure Time: 24 to 48 hrs.
- Performance Temp.Range: -40°F to 160°F
- Elongation: 300% D-412
- Tensile Strength: 300% D-412
Do not use near open flame. Avoid breathing solvent fumes and prolonged contact with skin. Do not take internally. If swallowed, do not induce vomiting. Call a physician immediately. Keep out of reach of children. Keep container covered when not in use. Do not thin. Dispose of in an environmentally safe manner. Cover air intakes during application and while drying.
Available in 5 gallon pails and 55 gallon drums.
Note: Coating Modified Bitumen Membranes with Aluminum Coatings
Karnak recommends coating modified bitumen membranes as soon as possible after the membrane is installed.
Karnak's experience, laboratory and field tests, as well as NRCA, RCMA and ARMA reports, indicate that aluminum coating will reduce the combined effects of ultraviolet rays, heat and moisture, which, especially on APP modified bitumens, enhance exudation that can cause discoloring and delamination of any surface coating.
COLD-PROCESS SYSTEMS AND COATINGS, EITHER EMULSION OR SOLVENT BASED, SHOULD ONLY BE INSTALLED ON DECKS WITH POSITIVE DRAINAGE.
PER NRCA, (NATIONAL ROOFING CONTRACTORS ASSOCIATION) "THE CRITERIA FOR JUDGING PROPER SLOPE FOR DRAINAGE IS THAT THERE BE NO EVIDENCE OF STANDING WATER ON THE DECK 48 HOURS AFTER IT STOPS RAINING."