Our SOMAY Product No. 842, SOMAY Elastomeric "ROOF MASTIC"®, is an excellent product to apply to any asphalt shingle roof to seal, protect and preserve the roof to make it absolutely waterproof and to help it last indefinitely.  However, since it is pigmented, it will have a color such as White, Spanish Tile, Terracotta, Machinery Gray or Sun Beige.  We cannot make a "Clear" "ROOF MASTIC" and retain the many properties that consumers are looking for.

Because we frequently have calls for a "Clear" product to apply to Asphalt Shingle Roofs, we have prepared this list of available SOMAY products, along with the following educational information. 

There are several very good and logical technical reasons why a "Clear" coating is likely to have a shorter life span than a pigmented coating,  including: (A) "Clear" coatings have no pigments to block the ultraviolet (UV) rays from the sun, so the UV rays pass through the "clear" film, causing degradation, hit the substrate behind the "clear" film and bounce back through the "clear" coating again, causing more degradation, so the "clear" coating will inevitably have a relatively shorter life span due to the harsh exposure one has on a roof surface;  (B)  The spreading rates of coatings are determined by the total volume of solids in the paint or coating formulation (NOTE:  everything except the solids will evaporate during the drying or curing process, and only the solids will remain on the painted surface), and the pigment part of a coating formula provides a very significant percentage of the volume solids.  Thus, a "clear" coating with no pigment will have relatively low volume solids, so the effective spreading rate will be relatively low – instead of 200 to 250 sq.ft./gallon for a pigmented coating, you may be lucky to get 125 to 175 sq.ft./gallon at two (2) mils dry film thickness (DFT) for a "clear" coating; (C) Applying any coating with relatively low volume solids to a flexible or infirm surface, such as poor quality or old, dried asphalt shingles, even old dried asphalt pavement, can result in the substrate curling and pulling apart, since the low volume solids coating shrinks more than a high volume solids coating as it dries and cures.   (Contrariwise, SOMAY "ROOF MASTIC" has high volume solids, so it does NOT cause the substrate to which it is applied to curl or pull apart);  (D) Since the physical mechanism by which you develop a waterproofing membrane is to apply multiple coats to develop a membrane of from ten (10) mils to twenty (20) mils dry film thickness (DFT), you can then calculate that you would have to apply many, many "Clear" coats to develop the necessary film or membrane thickness that will provide long term waterproofing.  You need to build the coating to at least 10 mils (= 10/1000 of an inch = 254 microns or micrometers) dry film thickness (DFT) for any reasonable waterproofing protection.  (We actually recommend 40 mils DFT for our SOMAY Elastomeric "ROOF MASTIC" System, which has lasted over 25 years on many roofs in south Florida, where we have very high UV radiation levels).

However, if you want to use a "Clear" coating, following is a list of "Clear" (non-pigmented) products available from SOMAY that can be applied to various surfaces to help seal, protect, preserve and waterproof the surface.  Normally one would apply multiple coats totaling ten (10) Mils Dry Film Thickness (DFT) for waterproofing purposes.  Let each coat dry and cure before applying the succeeding coat.

SOMAY Product No. 775-00, SOMAY Chattahoochee/Concrete Sealer, an Acrylic/Silicone resin-based "Clear" Sealer, solvent-borne (Xylene), high gloss finish - $20.99/gal.  Apply at the rate of 190 sq.ft./gal./coat = 2 mils DFT; apply five (5) coats to develop a ten (10) mil DFT for waterproofing purposes = 38 sq.ft./gal. for all five coats = $0.55/sq.ft. approx. theoretical cost.  

SOMAY Product No. 777-00, SOMAY "PST", Primer, Sealer, Topcoat, 100% Acrylic Latex (waterborne) "Clear" Coating. ""PST" has an initial appearance of skim milk and the viscosity of water, so it will easily penetrate into the pores of porous surfaces, to serve as a Primer/Sealer & Finish Coat. Dries absolutely "Clear" with a glossy finish.  Cost = $10.99/gal.  Apply at the rate of 154 sq.ft./gal./coat to develop 2 mils DFT; apply at least five (5) coats to develop a ten (10) mils DFT for waterproofing purposes = 30 sq.ft./gal. for all five (5) coats = $0.33/sq.ft. for 5 coats, theoretical cost. 

SOMAY Product No. 787-00, SOMAY 100% Acrylic Latex Varnish, (waterborne), "Clear", High Gloss - $17.99/gal.  Apply multiple coats at the rate of 346 sq.ft./gal./coat = 2 mils DFT/coat; 69 sq.ft./gal. for 5 coats = 10 mils DFT; = $0.26/sq. ft. theoretical cost.

SOMAY/Andek "Clearcoat 44", a Cyclo-Aliphatic "moisture-cured" Polyurethane, "Clear", Glossy  - $69.99/gal. (prices subject to change).  Apply @ 96 sq.ft./gallon for 10 mils DFT = $.79/sq.ft. theoretical cost.  Not normally stocked by SOMAY.  Available only by special order – requires payment with order.

SOMAY/LPL "DECOTHANE CLEARGLAZE", a single-component, aliphatic polycarbonate poly-urethane, moisture-cured, "clear", high-gloss, "wet look", non-yellowing, will cure when wet and immersed under surface water.  Solvent borne (xylene).  Cost: $229.99 per gal. in a 1.3 gal. pail (5-litre) (prices subject to change).  Apply at 80 sq.ft./gal. = 12 mils dry film thickness; 40 sq.ft./gal. = 24 mils DFT (recommended by LPL) = $5.75/sq. ft. theoretical cost.  Not normally stocked by SOMAY. Available only by special order – requires payment with order.

The numbers shown are theoretical for application onto a smooth, non-porous surface (like plate glass) and assume 100% transfer efficiency (= NO wastage).  Practical coverage will be less, especially if used on rough surfaces that are very porous and very absorbent.  One should also assume a minimum 10% wastage for brush or roller application; 20% wastage for airless spray application; 30% wastage for air-atomized spray application, and purchase enough extra material to make up for the wastage, based on the application method to be used.

Prices shown are "Pay & Pickup" at The Somay Paint Factory.  All prices are subject to change to reflect changes in costs.  Please call for current prices and stock status.

July 2005

"CLEAR" SOMAY COATINGS THAT CAN BE USED FOR

WATERPROOFING SURFACES

SOMAY Prod. No.	SOMAY Product Name	Total Vol. Solids %	Sq. Ft. /Gal /Mil DFT	Sq. Ft. /Gal. 2 Mils DFT	Sq. Ft. /Gal. 10 Mils DFT	Number of  Coats Needed  to Develop 10  Mils  DFT	Price /Gal., "Pay & Pickup"  @ Somay	Theoretical Cost / Sq. Ft. 10 Mils DFT
775-00	SOMAY Chattahoochee/ Concrete Sealer,  Acrylic/ Silicone Resin Xylene Solvent	23.7	380	190	38	At least 5 coats	$20.99	55¢
777-00	SOMAY "PST" Primer, Sealer Topcoat, 100% Acrylic Resin Water Solvent	20	325	163	30	At least 5 coats	$10.99	33¢
787-00	SOMAY Varnish 100% Acrylic Resin Water Solvent	43.4	692	346	69	At least 5 coats	$17.99	26¢
AN-C44	SOMAY/Andek Clearcoat 44 Aliphatic Poly- urethane Resin 1- Component Xylene Solvent	60.0	962	481	96	At least 4 coats	$75.99	79¢
LPL-DCG	SOMAY/LPL  "Decothane Clearglaze", Aliphatic Polyurethane 1-Component Xylene Solvent	60.0	962	481	96(rec. 40 sq.ft./ gal. )	At least 2 coats @ 80 sq.ft./coat = 24 mils for 2 coats	$229.99 per gal. in a 1.3 gal. pail	$5.75 @ rec. 24 mils $2.87 @  10 mils

July 5, 2005