Applications and Proper Care

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Planning Work on days when rain is not expected, and in temperatures of 65 to 75 deg. F. for comfort. The curing process requires an ambient temperature of between 55 deg. F to 140 deg. F. As an estimate, you will need about 3 to 6 hrs to apply Liquid Rubber EPDM on a flat (horizontal) surface of 240 sq.ft. Note: The spread rate of 42 - 46 sq.ft. a gal. is for a smooth surface. For a non-smooth surface you need to reduce the spreading rate.) This does not include surface preparations time (cleaning the surface). Allow another 16 to 20 hours after application, before the surface is dry to the touch and will take foot traffic. Although Liquid Rubber EPDM will immediately waterproof, even when wet, avoid heavy rain until dry to the touch (16 - 20 hours after application). Pitting may occur otherwise. A full cure will be achieved in 4 - 10 days after application, in consistent 70 deg. F. ambient temperatures. Higher temperatures will accelerate cure times and lower temperatures will extend cure times.

Surface Preparations After inspection and repairing structural faults and under skin corrosion, any asphalts or silicone type of caulking on the roof / surface, should be removed. Asphalt products are not compatible with Liquid Rubber EPDM, silicone rubber and Liquid Rubber EPDM will also not adhere to each other, and should be avoided. Any holes, gaps, seams, tears (of more than 1/16" wide) should be repaired or reinforced. Any potential weak areas should be reinforced. Holes and low spots should be filled with non-silicone caulking, or epoxies to "plug leaks" and level "low spots". Prior to coating, thoroughly clean and wash the surface with detergent (soap) and water, ensuring the surface is free of oils, dirt, debris and flaking paints, etc. If the surface has fungus, molds, algae or other biologicals, you may need to soak these areas in a 1/3rd bleach and water solution to kill the biologicals. Let soak until the solution evaporates to kill the biologicals. Applying Liquid Rubber EPDM You will still need to scrub (with a stiff brush) these areas with soap and water after soaking with the bleach solution, as some biologicals anchor onto some types of surfaces and must be mechanically removed even after killing. Thoroughly dry the roof prior to applying Liquid Rubber EPDM after cleaning. Unwanted splatters and drippings can be cleaned off with rags and xylene or mineral spirits when wet (within 4 hours after application ).

Before applying, mix the pre-measured catalyst by following label directions. A single application is preferable to multiple coats. On flat surfaces, material can be poured, spread with a squeegee and then evened out with a short nap roller. You can also use a paintbrush for small areas such as fish ponds, pipes, chimneys and roof flashings. Touchups may be applied as desired after initial film has cured and surface is first wiped with solvent. To insure its effectiveness it must be applied at a 20 mil layer. Apply with brush around flashings and edges using long, slow strokes. The Product will level itself when sufficient material has been applied.

Liquid Roof bonds very well to these coatings. Some of the earlier acrylic elastomeric formulations were prone to the development of underfilm corrosion. There usually is little visual evidence of this on the surface of the acrylic so small sections of coating must be removed from different parts of the roof to determine whether the condition exists and how severe it is. A visual inspection of the underside of the roof panels can reveal total penetration in the most severe cases.

Applying Liquid Rubber EPDM

You will need an electric drill (not cordless), a mixing shaft, a mop handled rubber squeegee, a mop handled short nap roller and a paint brush to apply Liquid Rubber EPDM manually. Use a brush for hard to Reach areas.

Broadcast & Spread using Use a short nap roller to smooth out entrapped air a rubber squeegee. and to evenly distribute the Liquid Rubber EPDM ( Short Nap = ¼ ") Using long mop type handles for the squeegee and the roller, will allow you to apply the product standing up and not on your knees. Standing up will be much easier than on your knees.

It is important to apply an even distribution of Liquid Rubber EPDM and at the correct thickness. Too little materials will produce too thin of a membrane, with inadequate adhesion and inadequate film strengths. Too much material will be wasteful, may cause under cure situations / long cure situations and may cause excessive swelling with some types of sheet rubber roofs. The optimum thickness for most purposes (non-immersion conditions) is one coat of 20 mils dft.

A) Clean and prepare the surface to be coated as directed.
B) Reinforce with Butyl Tape & Polyester Fabric if needed ( gaps, tears, seams, pin-holes, defects, etc. ) - check with our Technical Service Department for procedures.
C) Catalyze and apply Liquid Rubber EPDM on the surface / roof as described, use a squeegee, roller and brush to ensure an even application of 20 mils dft

To achieve a 20 mils dft. thickness, you should do a spreading rate calculation. For fairly smooth surfaces such as EPDM sheets, un-polished metals, fiberglass roofs, etc., use a spreading rate of about 40 sq.ft. a gallon. Reduce this for rougher surfaces, e.g., for surfaces such as steel troweled concrete surfaces, use a spreading rate of about 30 sq.ft. a gallon.

When calculating applied surface area, ensure you measure true surface areas. Example; if a panel is corrugated, take into account the corrugations in calculating the surface area of the panel. If you have not applied Liquid Rubber EPDM before, we would recommend you apply this in several pre-measured sections. The first section will give you a feel for the product and how fast you are able to apply this. You can then do larger areas in subsequent sections.

We recommend on the first section, you apply 2 gallons first, over a pre-measured 80 sq.ft. section By applying all the 2 gallons over this 80 sq.ft. area, in an even application, you will form a 20 mil dft. thickness when cured. The key is to spread the product evenly - not thick in some sections and thin in others. In 75 deg F to 85 deg F, the product will start to thicken up in about 4 hours, so you should plan your (work sections) with in that 4 hour time frame or less.

The first 2 gallons should not take you more than an hour, maybe two, but this will give you an idea of how fast (or slow) you can work. On subsequent sections, you may choose to put, say, 5 gallons over 200 sq.ft. sections, if it only took you an hour to do the first 80 sq.ft. section.

When ready to apply the first 2 gallons, follow the directions on the cans. Using an electric drill with a mixing shaft, run the shaft in the 2 gallons of Liquid Rubber EPDM (in a larger mixing container) until a vortex form. Pour the pre-measured (2 bottles) of catalyst into the vortex and let the drill run for about 15 to 20 minutes to thoroughly mix the Liquid Rubber EPDM with the catalyst. The catalysts are in plastic bottles and are bluish-purple in color. You will be able to see the bluish catalyst mixing into the Liquid Rubber EPDM if white.

Pour the catalyzed 2 gallons of Liquid Rubber EPDM onto the pre-measured 80 sq.ft. area in a serpentine manner. Use the rubber squeegee to quickly spread the product over the 80 sq.ft. as evenly as you can. Again, it is stressed that an even application is important. Do not have certain areas thick and other areas thin.

Use the squeegee to broadcast the Liquid Rubber EPDM quickly. The short nap roller (¼ " nap) is used to promote a more even distribution of product and to get trapped air bubbles out. After spreading with a squeegee, go over this area with the roller in slow long even strokes. Let the materials dictate your speed - so the roller does not pull materials along. Do several strokes with the roller to get an even and bubble-less application - turn the strokes 90 degree and continue the long even strokes over the same area. Use a paintbrush for nooks and crannies and areas where using a roller may be difficult.

You may initially see some roller / brush strokes. Liquid Rubber EPDM, however, is self-leveling and these roller / brush strokes will level off, after application.

By applying an even thickness of 2 gallons of Liquid Rubber EPDM on an 80 sq.ft. pre-measured area, you are ensuring the correct dry film thickness is achieved. When applying the next section, overlap an inch or two and blend in the overlap so you have a continuous and seamless membrane when cured

In 70 deg F., the applied Liquid Rubber EPDM will be dry to the touch in about 16 to 20 hours. This will still not be fully cured, but you will be able to walk on the roof / surface. In these temperatures, your newly applied Liquid Roof will be fully cured in about 4 to 10 days. Higher temperatures will accelerate the curing time and visa-versa, lower temperatures will prolong the curing process.

On some materials, such as EPDM rubber sheets, some swelling may occur due to solvent absorptions after applying Liquid Rubber EPDM. This is normal. This swelling will recover (shrink back) with time and heat. In 80 deg. F or so, allow 7 to 14 days to recover. In colder temperatures, recovering will take several weeks, as much as 6 to 8 weeks in 60 deg. F.

Some adhesives (used to bond the rubber sheets to the wood deck / structures) on existing structures, may degrade or of a poor quality and may not re-bond to the roof deck when recovered. Should this condition occur, you might need to re-bond the sheet rubber onto the roof deck with quality adhesives. As we have no control over the type of adhesives used on existing structures, we cannot be held responsible for such occurrence.

Using Liquid Rubber EPDM too thickly on a single application, will also cause excessive swelling and longer recoveries, thick single coat applications should be avoided. Overly thick (single coat) applications will take too long to cure, or for all intent and purposes, may not cure in the center.

Plywood and Wood Surfaces
When applying Liquid Rubber EPDM coating over non-porous wood and plywood it is our recommendation that all untreated wood and plywood products be sealed with an oil-based sealer prior to applying Liquid Rubber EPDM. Porous and unstable substrates will not apply / cure well with Liquid Rubber EPDM coating. Sealing the wood with a good oil-based sealer will reduce porosity of the wood, minimize trapped moisture, hence reducing the possibility of later rot and generally protects the wood from degradation. When using an oil-based wood sealer, follow the (wood sealer) manufacturer`s directions and their recommended dry times / in service times. Let the oil-based sealer set / dry, prior to applying the Liquid Rubber EPDM coating.

For treated or painted wood, clean the surface with soap and water to be free of residual oils, debris and dirt. Make sure flaking paints are removed. Make sure the surface is dry prior to applying Liquid Rubber EPDM, work in a rain free day above 55 deg. F, however 65 - 75 deg. F. would be ideal. For smooth surfaces, use a gallon for every 40 sq.ft. of area you intend to coat. Reduce this for rougher surfaces. If you are coating larger roofs and structures, you may have several seams and joints. If these gaps are under 1/16" gaps, you may coat over these seams without additional reinforcements or fillings. However, if you expect excessive expansions, movements or have larger gaps, you should reinforce these seams.

Asphalt based coatings Asphalt based coatings
Liquid Roof/Liquid Rubber should not be applied directly over an asphalt based coating. Water based acrylic elastomeric coatings may be used as intermediate coats before applying Liquid Roof/Liquid Rubber. Asphalt's based applications should be considered as being unstable materials and are excluded from warranty coverage. Caution-Latex house paints can not be substituted in place of the acrylic elastomeric coating. Click Here For Product Information on Our Elastomeric.

Adhesion

Adhesion will increase over time. Polar surfaces such as metal, concrete and wood result in stronger adhesion than non-polar surfaces such as asphalt and single ply EPDM sheet. Most weathered surfaces including single ply and thermoplastic membranes will have enough of a surface profile to anchor the Liquid Rubber.

Durability

By itself, the Liquid Rubber membrane will exhibit the characteristics of its EPDM chemistry, i.e. U.V. and ozone stability, excellent ponding water resistance and long-term retention of flexibility. However, since it is always applied to an existing surface,the condition of that surface will determine overall life expectancy. Do not apply Liquid Roof over cream color ALPHA rubber.

Liquid Rubber applied over generally sound single ply EPDM can extend its life another 20 years. The useful life of metal roofs also benefit greatly when Liquid Roof is applied. BUR systems often have existing problems such as delamination between layers, buckling and stress cracking. These are further aggravated by wet insulation which often results in severe corrosion and weakening of the metal supporting deck. Projecting a life expectancy for the EPDM Liquid Rubber membrane ultimately comes down to a case by case determination. When the EPDM membrane is compared to urethanes, acrylics and other elastomers in accelerated weathering and heat aging tests, the EPDM shows itself to be superior.

Surface Preparation

Liquid Roof/Liquid Rubber/Liquid Rubber may be applied on roof decks, gutters, structural steel, air conditioner enclosures, cooling towers, galvanized steel, unit heater flues, smoke stacks and chimneys, fiberglass and non porous masonry surfaces. Surface to be coated should be clean, dry and structurally sound. Fasten loose areas with adhesive (contact cement) or pop rivets. Oil or wax must be completely removed.

All surfaces to be coated should be clean and dry. Remove peeling paint and brittle caulking. Heavy build ups of asphalt roof cement should also be removed. Tighten any loose fasteners and replace those which are severely corroded. Repair or replace roof panels damaged by storms. Remove heavy rust with abrasive discs or wire brushes. Power wash all surfaces to be coated and allow to dry thoroughly. Caulk all gaps wider than 1/16 inch which are not expansion and contraction slip surfaces.

Remove loose portions of existing coatings and brittle caulk with scraper and wire brush. Whatever still has good adhesion may remain to be re-coated.

Rusty or pitted metal should be wire brushed to remove loose oxide. Tightly adhering corrosion may be recoated. Asphalt based aluminum coatings should be removed as much as possible by wire brush or abrasive disc. Roof cement should be removed and replaced with butyl caulk where necessary.

Repair torn rubber by re-gluing loose areas with contact cement. Coat exposed edges with contact cement to prevent solvent absorption from Liquid Roof/Liquid Rubber. A rubber patch may be applied over torn area if desired. Remove chalk from white rubber membrane by brushing with a detergent solution followed by a water rinse or working surface with a stiff brush. Smooth metal or plastic surfaces should be roughed up to improve adhesion of Liquid Roof/Liquid Rubber A de-glossing solvent may work on some plastics.

For Large Commercial Projects

Airless or Air Atomized spraying. Airless equipment needs only one hose from pump to gun but must generate 3500-4000 psi pressure and is limited in the length of hose which can be used because of high pressure drops. Air atomized equipment requires two hoses to the gun making it more cumbersome to maneuver plus the addition of a compressor.

Equipment specifications:

PUMP -capable of delivering 3-4 gal/min. at 3500-4000 psi HOSE if 3/8 inch ID max. permissible length is 150 feetwhen using .019 tip if 1/2 inch ID max. permissible length is 200 feet when using .21 tip

Temperature and Cure Conditions

When applying liquid roof the outside temperature needs to be at least 55 degrees for cure (dry) to take place; however night temperatures or temperature drops will not effect the product, it will simply not cure until the temperature reaches 55 degrees. Liquid Roof/Liquid Rubber may be applied at any temperature that permits it being spread onto surface. It will waterproof immediately upon application. The solvent will evaporate at a rate governed by temperature but will not be affected by relative humidity. Exposure to freezing temperatures before cure has taken place will not damage the films. The.time necessary to reach cure should not be a concern as this process will occur automatically. Exposure to sunlight will accelerate the curing process. The final film properties of the cured membrane will be the same regardless of the time required to achieve cure. Liquid Roof/Liquid Rubber will provide long term protection even under extreme exposure conditions. Please read all safety precautions and heed all warnings. It will waterproof immediately upon application.

Treating Rusted Areas

It is recommended that a corrosion inhibitive primer first be applied to areas where severe rusting has occurred. Liquid Rubber does not contain any corrosion inhibiting pigments but it is such an effective moisture barrier that it may be directly applied over light rust without a primer.

Fasteners

Caulking around fasteners is usually not necessary. The physical properties of the EPDM Liquid Roof/Liquid Rubber will produce a longer lasting seal around fasteners than caulks can because the latter will embrittle with age causing loss of adhesion and cracking.

Fabric reinforcing of seams and overlaps

Tight overlaps and standing seam joints do not need to be reinforced. Overlaps with gaps greater than 1/16 inch and corroded edges should receive fabric reinforcing. Apply a light coat of Liquid Roof/Liquid Rubber, center the fabric on the overlap and roll it out taking care not to create wrinkles; press fabric down with squeegee or wide spatula; spray apply a full coat of Liquid Roof/Liquid Rubber to seal top surface of fabric and roll back over to ensure coverage .

Mixing Directions

Proper incorporation and thorough mixing of the catalyst is critical to achieving desired cured film properties and should, therefore, be done with great care. Container is filled low to allow room for mixing as well as the addition of the catalyst. Insert mixing paddle in Liquid Rubber and mix for approximately one minute so that material is moving uniformly and has formed a vortex. Slowly add catalyst into this vortex at a rate which allows it to be incorporated without puddling. DO NOT pour catalyst on top of Liquid Rubber/Liquid Roof prior to starting mixer. After all the catalyst has been added, the mixer (if hand held) should be moved in a circular fashion around the periphery of the pail as well as up and down to insure that the catalyst is completely and uniformly mixed. Periodically scrape the sides with a rubber or metal spatula to incorporate the stagnant layer of material adhering to walls of pail.

Recoating Liquid Roof:

Since Liquid Roof cures by chemical reaction, a single heavy application will be preferable to multiple thin coats. A second coat will bond to a previous film but that bond will not be as strong as the internal bond within each layer. If a second coat is applied before the first has thoroughly cured, some wrinkling may result as the first coat absorbs solvent and swells. This will, however, recover as the solvent evaporates. It is generally recommended that only a single coat be applied over non-porous surfaces, the thickness of which can be varied as desired. Thicker films will take longer to cure through.