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Metal Roof FAQUpdated 3 months ago


Application

Question: Which products do I use to waterproof my metal roof? 

Answer: You can use Liquid Rubber Color Sealant (comes in colors, greater elongation), Liquid Rubber MetalSafe Sealant or Liquid Rubber Silicone Roof Coating (1 coat application). You will also need Liquid Rubber Seam Tape/Geo-Textile and/or Liquid Rubber Caulking.

Question: How much do I need?

Answer: How much sealant or primer you need depends on the specific product and the project it is being used for. For example: A roof with a pitch greater than 3/12 will require 1 gallon per 30 sq ft when using Liquid Rubber Color Sealant, while for a roof with a pitch of less than 3/12 you will need 1 gallon per 15 sq ft. See coverage rates below:

Liquid Rubber Color Sealant
Pitched roof (greater than 3/12) =  1 Gallon/3.78L per 30 sq ft.
Low Slope Roof (3/12 or less) = 1 Gallon/3.78L per 15 sq ft.
Liquid Rubber MetalSafe Sealant
Pitched roof (greater than 3/12) =  1 Gallon/3.78L per 30 sq ft.
Low Slope Roof (3/12 or less) = 1 Gallon/3.78L per 15 sq ft.
Liquid Rubber Silicone Roof Coating
Pitched roof (greater than 3/12) =  1 Gallon/3.78L per 50 sq ft.
Pitched roof (greater than 3/12) =  1 Gallon/3.78L per 50 sq ft.


Answer: To determine how much sealant or primer you need, divide your total square footage by the coverage rate provided. Example: You have a 300 sq ft of metal roof and the Color Sealant coverage rate is 1 gallon per 30 sq ft.  so 300/30 = 10 gallons of the Color Sealant. (Apply in multiple coats until all material has been used.). Coverage rates are expressed in final coverage and will include all coats needed to achieve membrane thickness.

Answer: Other factors to consider are that roof pitch and corrugation will affect your square footage. For example if you took your corrugated roof and stretched it out so it was flat it would be much longer than it looks. The same is true for pitch. To calculate your roof area multiply the length of your roof by the slope height and multiply by 2.  [(7ft x 9ft) x 2 = 126ft2]. You will also need to add 10-30% or more depending on how aggressive your roof corrugation is.

Question: Do I need Seam Tape or Geo-Textile? 

Answer: Yes. These products are used over the seams, around penetrations, etc. where a leak is most likely to occur. These products reinforce your coating at these area's to protect them from cracking during thermal and other movement.

Question: Which is better, Seam Tape or Geo-Textile? 

Answer: Seam Tape is the premium product as it offers it's own waterproof layer as well as a fiber reinforcement and is applied by peeling off the backing and pressing onto the surface. Geo-Textile will do as well as it offers a fiber reinforcement but it will require a bit more labor to install as it is applied via the 3-course-method. Click here for an example.

Question: Do I need Primer? 

Answer: No, Liquid Rubber products do not require a primer for metal roof applications if no rust is present.

Answer: If rust is present you will need to use a water-based rust primer or rust converter prior to application of your Liquid Rubber Coating/Sealant. (be sure to knock off any heavy scale first.). Except for Liquid Rubber MetalSafe Sealant which does not require a rust primer/converter.

Question: How do I clean my metal roof? 

Answer: Knock off any heavy scale/rust. Pressure wash to remove soils and debris. Use an appropriate detergent/cleaner if oils, moss/lichen is present (e.g. Liquid Rubber Deck and Patio Cleaner).  

Question: What tools do I need to apply my Liquid Rubber products? 

Answer: Most of our coatings and primers are applied using a brush or 10mm (3/8") nap roller. 

Answer: Some of them can be sprayed with airless, light industrial to heavy industrial spray units capable of spraying an elastomeric or bitumen coating (respectively), however, most homeowners will not have access to this equipment. 

Question: Do you have application guidelines/instructions to help me with my installation? 

Answer: Yes. Application guidelines can be found on our project pages (click here) or in the Application Guidelines and Technical Sheets section of this Help Center.

Question: Do you have application videos to help me with my installation? 

Answer: Yes. Application videos can be found on our project pages (click here) or on our YouTube channel (click here).

Question: What should I be looking for when first inspecting my metal roof? 

Answer: Look for damaged panels, loose or missing screws/fasteners, loose or damaged vent boots/caps/flashing/etc., rust, deterioration of weatherstripping (usually between panel laps)/caulking/previous repairs, deflected panels, discoloration and drainage issues (e.g. ponding, working gutters). When inspecting screws and fasteners make sure they have not been screwed down too tight, that the hole is larger than the screw or that it does not have a missing/deteriorated neoprene gasket (and is now loose).

Question: Do I need a new brush/roller every time I apply a new coat?

Answer: If you wrap your brush/roller in plastic (e.g. a grocery bag) you will slow down the curing process and you should be able to use the same brush/roller for your next coat. You can go a step further and place the plastic bag in the refrigerator (Do not allow contact with food)

Question: Can I coat over an existing coating or paint?

Answer: You can apply over most acrylic/latex, polyurethane, alkyd paint, epoxy paints/coatings with the use of our Liquid Rubber Multi-Purpose Primer and using proper cleaning/preparation techniques. Keep in mind that when you apply over an existing coating or paint, if that coating/paint peels, our coating will peel with it as it is bonded to the existing coating/paint and not directly to the substrate.

Answer: It is recommended to remove oil based or recently applied coatings with high solvent content prior to applying your Liquid Rubber products. (oil and water don't mix and solvents can deteriorate our water-based coatings)

Question: Can I apply one of your cheaper bitumen coatings first then coat over that with a white or colored product?

Answer: No. These are not compatible chemistries and will not provide and adequate bond. The bitumen will also eventually bleed through the colored coating.

Question: What if I have a problem or question with an application?

Answer: Our technical support team is here to help you, just reach out to call. email or chat with one of our representatives.

Answer: You very well may find the answer you are looking for in one of our application guidelines, which can be found on our project pages here.

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