• For RV roofs we recommend our Preparation D in order to remove any mineral deposits or dirt from the surface. For this you will need the following cleaners : Nu-Lift Cleaner and Stone Soap
Ensure your surfaces are fully cleaned and dried. If you have any rust on your surface, use a water based rust primer first.

Mask off areas that are not receiving any coating. Remove masking tape before material has fully cured.

We strongly recommend using the Fabric Reinforcement on all the joints. Apply a generous coat of SEMCO Liquid Membrane™ on the joints. 3” on each side of the joint and while product is still wet, put the Fabric Reinforcement over the joint and press it flat. Once Fabric Reinforcement is on, apply another coat of SEMCO Liquid Membrane™ across the Fabric Reinforcement to encapsulate it. Let it dry completely before resuming to next step.

Make sure any pre-treated areas are completely dry before using a 1/2-inch nap roller or brush to apply your first thin coat (about 0.015 inches thick) of SEMCO Liquid Membrane™ over the entire surface. Wait for this first layer to dry until you can touch it or walk on it without leaving a fingerprint or tracking any sticky residue. Once it is ready, roll on a second thin coat in the opposite direction—for example, if you rolled side-to-side first, roll up-and-down this time—to ensure solid coverage. Let this topcoat dry for about 1 to 2 hours at normal room temperature until it feels dry to the touch, keeping in mind that it will naturally turn a lighter color as it dries. Finally, inspect your work closely for any tiny pinholes, bare spots, or defects, and brush a little extra membrane over those areas so your finished, fully sealed surface reaches the required total thickness of 0.03 to 0.04 inches.

Curing time depends on temperature, humidity and airflow, however typically initial cure is within 6 - 7 days as per specific product recommendations. Avoid contact with water during the curing period.

• For clean up use warm water to clean brush or roller right after use.
• For optimal bonding we highly recommend preparing the surface as mentioned above for best results.
• Stir up the product well before use in order to mix up the color pigments.
• Avoid application in direct sun light in the afternoon or temperatures of over 85F as it might cause the product to dry too fast before it can adhere to the substrate
• It can not be applied to wet substrates or substrates still containing moisture, else it will not cure correctly and stay tacky. Max. rest moisture in substrate can be up to 3%. If you are unsure about the moisture content, have it measured prior to application.
• Application on non porous surfaces such as metal or fiberglass : Apply thin coats as this will allow for the product to cure faster.
• Cure times are displayed in our curing chart. However if coats have been applied too thick, the surface might feel tacky. This is a sign of trapped moisture. If you have left over product, apply a very thin coat over the entire surface. The surface needs to be fully cured and hard before being fully submerged.
• It is always advisable to apply a small test patch in an inconspicuous are to ensure adequate adhesion prior to full application.
• If you have multiple containers of SEMCO Liquid Membrane™, we highly recommend to either mix them together or use one container for the last layer to get color consistency.