Applying Elastomeric Roof Coatings

Material List:
  • House Wash
  • Elasto Patch
  • Caulk
  • Flashing fabric
  • Bond-it primer
  • Bus Kote
  • Flexi-Clear (optional clear coat)
Scrape off all loose, peeling, blistering, chipping, cracking or flaking coating. Wire brushing, pressure cleaning, power sanding or sandblasting may be used to remove powdering and chalking coating. To remove dirt, grease, etc., wash with water and detergent and then rinse thoroughly with clean water. To remove mildew, fungus, etc., scrub with Hy-Tech House Wash or a solution made with 16 fluid ounces (473 mL) of liquid household bleach and 2 fluid ounces (59 mL) of detergent in one gallon (3.785 L) of water. Rinse thoroughly with clean water. Patch all cracks and seams. You should have a completely clean and firm surface before any new coating is applied.

Make any necessary repairs or replacements to damaged or leaking roof materials. Avoid using cleaners with built-in wax or silicon additives since this may affect coating bond.

CAUTION! Look out for these trouble spots:

Flashings: All flashings should fit tightly to the roof. They should be held firmly by screws or taped down. Damaged or rusty moldings and flashings should be repaired or removed and replaced.

Stacks and Vents: Stacks and vents remove excess moisture and fumes from your motor home or RV. Faulty or poor performing stacks or vents will allow moisture to accumulate between the ceiling and the roof and cause condensation. They should be repaired or replaced, or added, if necessary.

Seams, Cracks, and Stress Areas: The same repair procedure generally applies to seams, cracks, and stress areas. Remove all dried-out caulk or coating. On seams, tighten screws if necessary. Seams, cracks, and stress areas over 1/4" wide should be repaired using Hy-Tech Polyester Seam Patching Tape. Always put membrane over the entire seam - not just the portion that looks faulty. Apply Elasto Patch over membrane.


NEW METAL OR COMPLETELY STRIPPED SURFACES: Prime with one coat #15 Aqua Prime, an adhesive primer.

RUSTY METAL: Remove scaly rust and treat with Ospho or our Rust Reform. Prime with #15 Aqua Prime.

PREVIOUSLY PAINTED SURFACES: If powdering or chalking comes off on the hand when rubbed over the surface, clean by power washing. Then a coat of Hy-Tech #1220 Bond-It should be applied, according to directions, before applying Hy-Tech Bus Kote.

APPLICATION: Apply Hy-Tech Bus Kote only at temperatures above 50° F (10° C). Stir thoroughly before using and occasionally while using. May be applied to dry or slightly damp surfaces, using brush, roller or spray. Apply generously, working the Coating into pores and cracks. Try to apply the Coating as smoothly as possible. A minimum of two coats is recommended. Two thin coats are always preferable to one thick coat. For a truly maintenance free finish protect the finished white coating with one coat of Hy-Tech gloss "Flexi-Clear" a stain resistant elastomeric clear coat. Just as clear coats are used to protect todays automotive finishes, Flexi-Clear will keep your bright white roof coating clean and bright while further reducing UV's. Maintaining your roof is easy as you simply apply one coat of clear Flexi-Clear every 5-6 years.

THINNING: Hy-Tech Roof Coatings are ready to use and should be applied full strength as they are received in the can. Any thinning of the Coating will reduce the percentage of solids, which will adversely affect the durability of the applied coating.

COVERAGE: 100 to 150 sq. ft./gal.

DRYING TIME: Drying time will vary depending on surface and air temperature, humidity, wind or air movement, exposure to sunlight, etc. Under ideal drying conditions, Hy-Tech Roof Coatings form a dew and drizzle resistant film in approx. 30 to 60 minutes after application, and dries sufficiently in approx. 3 or 4 hours to permit the application of a second coat. A longer drying time will be required if the surface being coated is not completely dry, is colder than 50 ° F, if too thick a coat is applied, if the relative humidity is higher than 90%, if the air is calm, or the surface is not exposed to direct sunlight.

CLEAN UP: Any drips, splatters, over-spray or spills on shrubbery, walkways, drive-ways, or sides of mobile homes must be cleaned up immediately before Coating dries. NOTE: If Coating is spilled or splashed remove it at once, using water from a hose, warm soapy water, or alcohol solvent. Coating not removed before it dries will be almost impossible to remove. Clean hands, brushes, rollers, tools and other equipment immediately after use in warm soapy water.

WEATHER CONSIDERATION: Before application, KEEP FROM FREEZING. Apply only at temperatures above 50° F. Apply only when weather will be fair for a sufficiently long time for the Coating to dry. Do not apply late in the afternoon or early evening when a heavy dew could develop on the coating surface before it dries thoroughly. A very heavy rainstorm, such as those common in tropical climates, could wash the Coating off during the first few hours after application, if it has not dried thoroughly. Spray painting makes short work of applying roof coatings, see our tutorial on "How to Spray Paint", it's easier than you think.