Hello, in the roofing project, a 5cm arc is made at the junction of the leveling layer and the protruding roofing structure. What about this arc crack (with 1: 3 cement mortar)?

The function of circular arc is because waterproofing membrane is easy to break at right-angle corner, especially the previous linoleum will break, so it is required to make circular arc or splay angle in this part to solve the problem of membrane bending. Therefore, the size of the arc is related to the thickness and type of the coil.

Knowing the function of arc can solve your problem. Cracking of cement mortar will not affect the waterproof layer, but it is beneficial to waterproof. As a plastering project, smoothness and no cracking are the basic requirements. Therefore, serious cracks and cavities need to be repaired. Generally, cracks can be repaired with cement mortar or not.

Waterproof coating does not have the problem of coil corner, so it is not necessary, but it is not wrong to make an arc.