Specification & Codes
Guide Specification for the Protection of Polyurethane Foam Roofs Using Karnak RC-W Elastomeric Coating
Guidelines & Specification
This Guide specification covers the protection of PUF Roofs using Karnak RC-W Elastomeric Coating. In addition to the guidelines set forth in this guide specification, all NRCA accepted roofing practices must be followed.
2.1 For installation over new foam roofs proceed to step 3.0.
2.2 For existing previously coated PUF roofs power-wash the surface to remove any surface contaminants including: dirt, mildew, oils and loose coatings.
2.3 Cut-out all "crumbled" or "wet" areas of foam and allow to dry fully.
2.4 Fill in the open areas using an instant foam froth pack. Allow to cure per manufacturer's recommendations. Cut and level off all excess foam.
2.5 Vacuum remaining dust off to ensure a clean surface.
3.1 Apply Karnak No. 96 Elastomeric Primer at a rate of 1/2 gallon per 100 square feet.
3.2 Wherever the "new" foam meets the "old" foam, apply a 10" wide strip of Karnak RC-W Elastomeric Coating (White).
3.3 Embed a 4" or 6" strip of Karnak Resat-Mat directly into the 10" strip of newly applied RC-W Elastomeric Coating.
3.4 Immediately following the embedment of the mat, apply a second 10" wide strip of RC-W Elastomeric Coating (White) at a rate of 1.5 gallons per 100 square feet.
4.0 Base Coat
4.1 Apply a coat of Karnak RC-W Elastomeric Coating (Gray) at a rate of 1.5 gallons per 100 square feet. Allow to dry 24 hours.
5.0 Finish Coat
5.1 Apply a coat of RC-W Elastomeric Coating at a rate of 1 - 1.5 gallons per 100 square feet. Allow to dry 24 hours.
Note : The above specification is offered as a service to the specifier, Karnak Corporation does not practice architecture nor engineering and advises,that a registered architect and/or engineer be employed as required relating to any known structural defects or circumstances not covered by this specification.