Thompson\'s Emergency Roof Repair Mastic has been developed from technology used on North Sea oil rigs, Thompson\'s Emergency Roof Repair Mastic is a trowel applied mastic with the ability to adhere to virtually any roofing material even underwater. With added fibres and a high solids content, Thompson\'s Emergency Roof Repair Mastic has been developed for filling, plugging and repairing cracks and splits, targeting leaks at the source of the problem. Thompson\'s Emergency Roof Repair Mastic is an all weather solution, its hydrophobic formula actively repels and displaces water during and after application instantly forming a watertight seal that does not require time to cure before it delivers full weatherproofing protection. Will adhere to virtually any material even under water. Suitable for use on flashings, gutters, roof lights and valleys.