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Torch Down/Mod-Bit Roofs FAQUpdated a year ago


Application

Question: Which products do I use to waterproof my torch down/mod-bit roof? 

Answer: You can use Liquid Rubber Color Sealant (comes in colors, greater elongation), Liquid Rubber Waterproof Sealant (good for constant submersion) 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 Waterproof 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 will affect your square footage. For example if you took your pitched roof and levelled it out so it was flat it would be longer than it looks. 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]. 

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: Primer is not commonly needed for these types of roofs.

Question: How do I clean my mod-bit/torch down roof? 

Answer: These types of roofs are a little tricky as it can be easy to trap moisture under the surface and power-washing can damage the existing material. Compressed air can be used (again watch out for damage) and roof sweepers. Be sure to remove any moss/lichen that is present and treat the area with a mild bleach solution as these become rooted in the surface. Grease/oils must be cleaned with a degreaser or cut out and patched.

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

Answer: You can use a brush or 10mm (3/8") nap roller or push broom.

Answer: It is also possible to be sprayed with airless, heavy industrial spray units capable of spraying a bitumen coating (e.g. Graco GH833), 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 mod-bit/torch down roof? 

Answer: Look for damaged sheets (often at upturns), failed seams, blisters (where the system has become unbonded from the substrate) loose or damaged vent boots/caps/flashing/etc., deterioration caulking and previous repairs, discoloration and drainage issues (e.g. ponding, working gutters), improperly installed drains (e.g. sits too high), moss or lichen, trapped moisture (use an infrared scanner). 

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 our bitumen's over both bitumen and acrylic coatings, but it is not recommended to apply our acrylic or silicone coating over a bitumen.

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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