Intersection Of Wall And Roof Waterproofing

Anywhere surfaces intersect on a roof is a prime spot for water seepage.

Intersection of wall and roof waterproofing.

A waterproofing seal installed at the intersection of the roof and chimney and used to prevent moisture penetration. The flat roofing material must go up the wall a minimum of 12 or up the wall and over the top of the wall if the wall is less than 12 high. 82 build supplement flashings section 4 roof wall intersections figure 79b step 2.

Step 2 flashing 2 covers both the apron flashing upstand and the wall underlay. These problem areas include the edges of skylights and chimneys soil stacks vent fans and roof valleys as well as the intersection of the roof deck and dormer walls. Yes even flat roof to wall intersections are not being properly done. Figure 79a flashing the junction step 1.

Above we show a feeble attempt at flashing and counter flashing at the roof wall intersection of a low slope roof. Typical waterproofing details of foundations above the roof slab shall be followed as per approved shop drawing. Unauthorized entry shall be restricted to the waterproofing areas. The installer tacked a row of asphalt shingles to the wall caulked their top edge and hoped for the best.

On completion of waterproofing membrane and before undertaking any further activity it shall be tested by plugging the outlets and flooding 50mm above the highest. The omittance of the termination metal leaves an opening at the top of the coping and allows for moisture infiltration at the space between the parapet wall and the structural wall. Proper roof wall flashing example.