Plan your coating
Choose a day that is clear with a slim change of range. Ideally, you will be working in temperatures ranging from 65° - 75° F. Note that curing requires at least 55° F. You can cover between 42 to 46 square feet per gallon if you want a smooth surface. Reduce spread rate if you prefer a non-smooth coating. When planning your project, keep your prep time in mind. Your coating is immediately waterproof, but requires at least 16 hours before it is dry enough to walk on or touch. It is best to choose a day without rain or snow since pitting is a possibility. The total cure time depends on temperatures, but often happens within 4 to 10 days in 70°+ F temperatures. If you live in a hotter region, you can expect a faster cure time. For any separation in the joints we suggest filling them with the Rutex caulk found on or order form. This Caulk has been field tested and is compatible with the liquid epdm and will not void its warranty. It is free of any solvents or isocyanates and is 100% volume solids. More information can be found HERE (RUBEX CAULK)
Prepare your surface
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 with solvent otherwise the product may swell and wrinkle and will not be covered under warranty. We suggest applying one coat of the ProFlex Primer in the event you feel any oils or waxes cannot be removed. Remove loose portions of existing coatings and brittle caulk with scraper and wire brush. Whatever still has good adhesion may remain to be recoated. Rusty or pitted metal should be wire brushed to remove loose oxide. Tightly adhering corrosion may be directly coated with Liquid Roof®.
Make sure any repairs and issues are fixed first. Check for caulking and corrosion. Remember that asphalt is not a good fit for Liquid Rubber. Silicone and Liquid Rubber also do not work well together. Reinforce weak areas and fill holes with caulk that does not include silicone.
Clean the surface thoroughly before beginning your project. Remove debris, flakes, dirt and oils. Remove any live issues, such as fungi or mold, in a 1/3 cup bleach to water solution. Allow the solution to soak until it evaporates. After removing live problems, scrub the entire area with a stiff brush and soap and water solution. The area should be completed dried prior to application of Liquid Rubber. You can wipe off any splatters within four hours of application.
Thoroughly combine the pre-measured catalyst and double check the directions. Remember that one application is better than multiples. Flat surfaces are especially simple since you can pour the mixture and spread it with a squeegee. Complete the coating with a nap roller. Paintbrushes are another option for smaller areas. You can touch up areas for cosmetic purposes after the first application has cured, and the area has been wiped with a solvent. Apply the solvent at a 20 mil. Layer, and use a brush along edges with a long stroke. Liquid Rubber is capable of leveling itself.
Liquid Roof is a great product for almost every surface. However, if there is an old coating, it's important to check for underneath corrosion. You must remove a section of coating to check for it. If corrosion has occurred, it is often very easy to spot once sections are removed.
How to Apply Liquid Rubber EPDM
Gather these tools prior to application:
- Electric drill
- Mixing shaft
- Mop-handled squeegee
- Paint brush
- Short nap roller
The nap roller is used to smooth the surface. The Squeegee removes trapped air and also helps with an even application. Choose a squeegee and nap roller that is comfortable. Most people prefer longer handles to apply the product while standing.
Even distribution and appropriate thickness are critical. An ideal thickness is 20 mil. and creates the best protection. A thin coating does not provide adequate reinforcement, and a thick coating can cause swelling.
Calculate your spread rate to achieve 20 mil. thickness. Smooth surfaces require approximately one gallon for 40 square feet. Rough surfaces require around one gallon for 30 square feet.
Calculating surfaces can be tricky if some areas are smooth and others are not. Pre measure separate sections and plan accordingly. It is best to separate the surface into smaller, manageable regions. This also helps you get an idea of how long it takes you for certain areas.
Try this Technique
Select a smooth 80 square foot section and prepare two gallons. This should result in a 20 mil. thickness after curing has taken place. Expect the product to thicken in four hours if you are working in 75° - 85° F temperatures. This section should take no longer than one hour to complete, although some slower workers might require longer. Figure out how quickly you work, and plan future sections accordingly.
Mix the product with a mixing shaft until you see a vortex. Now it is time to pour the catalyst into the cortex. Allow the mixing shaft to mix for an additional five minutes. This is the only prep work necessary for the product. It is now ready to pour onto the surface. Drizzle the product in a snakelike pattern. Even out the application with a squeegee, paying particular attention to the evenness of the spread.
After spreading the product evenly with the squeegee, go over it again with the nap roller. Use slow, long, even strokes. Utilize the nap roller in all directions. A paintbrush can be used for crannies and smaller areas that a roller can snot reach. Do not worry if you see brush or roller strokes. Liquid EPDM is self-leveling. When starting the next section, overlap the application by two inches to ensure a perfect, finished surface.
The surface may be dry to the touch within 24 hours, but it is still not cured. However, you can walk on it. If you notice swelling, do not panic. This is common, and it will correct itself within a few weeks. This correction can take longer if you live in colder regions.
Applying EPDM Liquid Rubber®
Here is what you will need:
- Electric drill (cordless drills will be effective)
- A mixer for a can or pail.(paddle mixer) available on our order form
- A rubber squeegee attached to a broom handle.
- One Short nap roller approx. 1/4” attached to a broom handle.
- Paint brush
- Rubber spatula
- Mineral spirits or Xylene for clean up
- Bag of Rags
When using the broom handles it will allow you to apply the product standing up vs having to get on your knees. The paintbrush is for the corners and hard to reach sections. Broadcast the material in a letter “S” manner and then spread it using the squeegee. Follow up with the ¼” nap roller to smoothen any trapped air and equitably distribute the EPDM Liquid Rubber®. Any mistakes such as drips or platters should be cleaned off with rags. The Xylene and/or mineral spirits should only be used on the Liquid EPDM when it is still wet not to exceed 4 hours after application.
Using Liquid EPDM on Plywood or Wood Surfaces
Plywood and certain woods are especially porous. These surfaces should be sealed using an oil-based material before using Liquid Rubber. Otherwise, the product will not cure. Sealing the surface first protects the wood, minimizes the risk of rot, and reduces moisture. Follow the directions of your oil-based sealant of choice.
Applying Liquid EPDM to painted or treated wood is very similar to application on any other suitable surface. Clean the area and check that flaking pain is removed. Apply Liquid EPDM just like any other surface. Wood application are not covered by warranty as it is impossible to verify the condition of the wood i.e. rotten wood or wood that has absorbed water.
Asphalt and EPDM
Do not apply Liquid Roof directly onto asphalt. Instead, apply a water-based acrylic coating first. Follow the acrylic products manufacturers directions and allow it to dry completely. Asphalt is not included in Liquid EPDMs warranty. Note that only acrylic-based products should be used prior to application, as latex will not work.
Get More Product Information on Our Elastomeric
When Will Total Adhesion Happen?
It will take time for complete adhesion to happen. Materials like metal, wood, and concrete naturally cause a stronger adhesion. The time required depends both on the temperature and the material.
How Strong is EPDM?
Proper application results in UV and ozone resistance, holds up to standing water, and very long-term flexibility. However, keep in mind that EPDM can only be as strong as the existing surface. EPDM can increase the life of a surface, but it should not be used with a crumbling or dilapidated surface.
Generally, Liquid EPDM can extend the life of a surface for 20 additional years. However, there are many qualifiers to consider. Twenty years is not a guarantee. Overall, EPDM is better than all other elastomers, but customers should assess the condition of the surface before applying EPDM.
Prepping Any Surface for Liquid EPDM
You can apply EPDM to many places including:
- Air conditioner enclosures
- Cooling towers
- Galvanized steel
- Heater flues
- Metal roofs
- Roof decks
- RV roofs
- Smoke stacks
- Structural steel
Check that the area is clean, dry, and in good condition. Use contact cement to adhere loose areas. Remove any flaking caulking, paint, rust, oil or grease. Sometimes replacements are in order. Power washing is important before applying Liquid EPDM. A scraper and wire brush can be used for caulk, aluminum coatings, roof cement and rust. Replace roof cement with butyl caulk.
You can use a rubber patch to repair torn areas. Chalk requires a detergent cleanse and rinse using a stiff brush. Improve adhesion on smooth surfaces by roughing it up.
Big Commercial Projects and Liquid EPDM
Properly cleaning and prepping large surfaces can be difficult. Use an air atomized or airless spray machine to quickly get the job done. You will need 3,500-4,000 psi of pressure. The airless machine requires one hose, while the air-atomized machine requires two. CLICK HERE for more information.
Specs for Equipment:
A pump can deliver 3-4 gallons at up to 4,000 psi if the hose is 3/8. You have up to 150 feet if using a .019 tip at ½. You get up to 200 feet with a .21 tip.
Curing and Temperatures
Remember that 55° F is required for curing. Temperatures can drop at night, which can slow the curing process. However, you can easily spread Liquid EPDM at any temperature. Humidity and freezing temperatures will not impact the product. Liquid EPDM will cure, but the speed is governed by temperatures.
Tackling Rusty Areas
Apply a corrosion primer before Liquid EPDM. Our products to not include corrosion inhibitors. However, if the area is only slightly rusted, Liquid EPDM is often a strong enough moisture barrier to work without a primer. Judge your surface wisely.
Fasteners and Caulk
It's almost never necessary to caulk around fasteners. Liquid EPDM provides a stronger seal than caulk, and decreases your prep time.
Seam and Overlap Reinforcement
There's no need to reinforce seam joints and close overlaps. However, reinforcement is recommended for gaps larger than 1/16" and for edges with corrosion. Apply Liquid EPDM first, put the fabric on the overlap, roll it to remove wrinkles, and apply a top coat of Liquid EPDM.
Liquid Roof Second Coats
Multiple coats of Liquid EPDM is not recommended. The first coat is the strongest, which is why ideal thickness is important. If you do apply a second coat, ensure that the first has completely cured otherwise, wrinkling and swelling are possible.
Get information on RV roof repair HERE