User Guide - Impermax B1K Black Liquid Roof Coating

Is the current roofing on your house or shed due for replacement, or are you dealing with a leak? Normally, you would hire a roofer to carry out the repairs, but did you know that you can also do this yourself using Impermax liquid roof coating? It’s very easy and much cheaper than hiring a roofer. Impermax is available in black (Impermax B1K) and white (Impermax LY). In this article, you’ll learn how to apply the black Impermax and what you’ll need for it.

If you have any questions about Impermax, feel free to contact our customer service team.

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What is Impermax B1K?

Impermax B1K is a high-quality black liquid roof coating. The product consists of a one-component polyurethane-bitumen with solvents and forms a seamless, waterproof membrane. The coating fully adheres to the substrate, eliminating the need for nailing, torching, or gluing. In addition, in the event of a leak, water cannot run underneath the membrane, making leaks easy to locate and repair.

If you have any questions about Impermax, please feel free to contact our product specialists.

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What do you need? 

To treat your roof with liquid roofing, you will need the following products:

• Impermax B1K
• Impermax Primer (if required)
• Impermax Thinner
• Polyester fleece (if you plan to apply the coating in two layers)
• Spiral mixer + Drill
• Fleece rollers + Paint roller frame
• Brushes
• Nitrile gloves
• Safety goggles

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Application instructions

Impermax is very easy to use — you don’t need to be a professional roofer to apply this roofing yourself. Watch the instruction video below, where we demonstrate how to apply Impermax B1K, or follow the step-by-step guide below.

Step 1. Surface preparation

Proper surface preparation is essential for a good result. Make sure the roof is clean and free of dust, loose particles, oil, and other contaminants. Also, repair any cracks in the roof with Impermax fleece.

You can apply Impermax at temperatures from 5°C (41°F) under suitable weather conditions. There should be no water on the roof, and it should not rain within the next 4 hours.

Step 2. Applying primer 

In certain cases, we recommend applying a primer to improve adhesion of the roof coating. Working on EPDM, PVC, or zinc? Treat the surface with Impermax Porosity Sealer Flex Primer. For bitumen roofs, applying a primer is also recommended to prevent “bleeding.”

• Apply the primer with a roller, brush or airless spray equipment.
• Allow the primer to cure for about half a day or overnight before applying Impermax B1K.

Step 3. Preparing and applying Impermax 

Impermax can be applied in two ways: as a single-layer system over existing roof sheets such as bitumen, EPDM, PVC, and asphalt (consumption: 1.6 kg/m²), or as a full roof system combined with polyester fleece (consumption: 2.5 kg/m²).

Single-layer system

1. Open the packaging and mix the contents with a spiral mixer until you get a homogeneous mixture. Let the product rest briefly to release air bubbles.
2. Thin the material with a maximum of 5% Impermax Thinner.
3. First, treat details such as edges, skylights, and chimneys with a brush.
4. Pour a generous amount of Impermax onto the roof and spread it with a fleece roller. Use the roller primarily to distribute the material - not to roll it - so that the layer maintains sufficient thickness.
5. Let the roofing cure for at least 4–8 hours (depending on temperature and humidity). Consult the technical documentation for exact curing times.
6. If needed, apply a second layer within 3 days.

Two-layer system

1. Open the packaging and mix the contents with a spiral mixer until homogeneous. Let the product rest briefly to release air bubbles.
2. Thin the material with a maximum of 5% Impermax thinner.
3. First treat details such as edges, skylights, amd chimneys with a brush.
4. Pour a generous amount of Impermax onto the roof and spread it with a sheepskin roller. Use the roller mainly to distribute the material - not to roll it- so that the layer thickness remains sufficient.
5. Place the polyester fleece onto the wet Impermax layer with a 10 cm overlap.
6. Roll the fleece into the material and let it cure for 24 hours.

7. Then apply a second layer of Impermax and allow it to cure. The curing time depends on the surrounding conditions. Refer to the technical documentation for an overview of the recommended curing time for Impermax B1K.

Two-layer system

• Open the packaging and mix the contents with a spiral mixer until homogeneous. Let the product rest briefly to release air bubbles.
• Thin the material with a maximum of 5% Impermax thinner. 
• Apply the liquid coating with a sheepskin roller or brush, spreading the material evenly. 
• Place the polyester fleece onto the wet Impermax layer with a 10 cm overlap.
• Roll the fleece into the material and let it cure for 24 hours.
• Apply the second layer of Impermax on top and allow it to cure. Curing time depends on environmental conditions. Consult the technical documentation for recommended times.

Step 4. Curing

Allow the Impermax to cure fully. Under normal conditions, the membrane reaches 90% of its final properties after 3 days. After 1–2 days, the roof is walkable, but full hardness is achieved after 10–15 days. We recommend waiting this period before exposing the roof to water. After opening, Impermax can be stored for up to 6 months with the lid tightly closed. Tools can be cleaned with acetone.

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More information about roof coatings

Want to apply Impermax liquid roof coating yourself but still have questions? Feel free to contact our product specialists via email, telephone or WhatsApp. We are happy to advise you on the right products for your project!

 

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Frequently asked questions