Sealing Pipes, Posts and Parapets on a Roof

1. A rusted base

Around the rusted post the membrane had torn and come loose. Small openings like this are how water finds its way to the ceiling below.

2. Sealing the post

The spot gets a dark primerPrimerThe thin first coat that goes on before the main material. It binds dust, seals the pores and helps paint or waterproofing stick firmly. and then a white waterproof coatingElastomeric waterproof coatingA thick, rubbery waterproof paint for flat roofs, parapets and roofs. It stretches without cracking as the building expands and bridges hairline cracks. that wraps around the post and bonds to the membrane around it.

3. The base of a pipe

Every pipe coming out of the roof is sealed the same way, so there is no open joint left at its base.

4. The solar heater feet

The feet of the solar water heater stand on the membrane. Each one gets its own white square.

5. Where the roof meets the parapet

The corner where the floor meets the parapetParapetThe low wall around the edge of a flat roof or balcony. The joint between it and the floor is one of the most common places for leaks. is another weak spot. First a dark primer goes along its whole length.

6. White waterproofing on the parapet

The white coating covers the corner and runs up the parapet, so rainwater flows over the joint instead of into it.