November 20, 2013 Roof Report

Case Study

1. Standing water is noted on both the upper and lower roof areas. This is due to a minimum deck slope design and the existence of only one primary drain per level.

2. In select locations on the upper roof area a complete void of UV protection is apparent. This needs to be addressed in the coming summer by application of 2 coats of an aluminum roof paint.

3. The primary upper roof drain is clear of blockage, and utilizes a debris basket. Unfortunately, as is commonly found on flat roofs with internally plumbed drains, this drain now sits at a high spot on the roof level

4. Secondary scupper drains are plumbed through the upper roof’s north wall and discharge onto the lower roof level courtesy usage of aluminum down pipes.

5. A third “level or degree” of upper roof drainage exists in the form of an elevated overflow scupper. This is a favorable feature.

6. A recent addition of a shaft roof is appropriately installed and is well protected from harmful UV rays. This small roof area also exhibits a positive slope for drainage purposes

7. Lead hardware is used on all plumbing vent stacks. This detail is typical for this age and style of roof. As untreated lead erodes in standing water, these vent stacks should receive added attention with Aluminum paint when that maintenance obligation is addressed.

8. Minor membrane wrinkling was witnessed on the upper flat roof area. Although not ideal, the degree of membrane bridging is not an immediate concern at this time and should be thought of as a typical result developed during the evolution of an aged APP roof system.

9. Metal cap flashings have been sealed with a mastic or emulsion. This seems to be doing the job it is intended for however a flexible caulking is the sealant of choice on metal flashings

10. An aged skylight with reinforced glass panes would benefit from rust paint being applied to all metal surfaces and inspected and monitored for glass integrity.

11. The sloped roof between the upper and lower roof levels is also an APP system. There is little UV protection provided.

12. The primary drain on the lower roof is situated in a sump box. Diligence must be kept to keep this area free of debris build up.

13. Roof vents, located in standing water puddles, have been protected against erosion and rot by the application of a granular SBS torch on membrane up the vertical face of the vent. This is preventative thinking at work.

14. Select areas on the lower roof’s perimeter flashing require a caulking upgrade.

14. Select areas on the lower roof’s perimeter flashing require a caulking upgrade.

Customer:
Project Completed: n/a
Type of Roof: modified bituminous membrane roof system
Materials: n/a
Location: Vancouver, B.C.

Roof Analysis:

The property’s primary waterproofing provider is an APP (Atactic polypropylene) modified bituminous membrane roof system that exhibits various stages of UV protection. Adequate metal flashings exist on perimeter edges. Primary drains are internally plumbed. The structure’s roof areas are divided into a major upper roof area and a major lower roof area. It is expected that additional roof systems exist under this top layer of APP membrane however no roof systems were cut-tested to inspect underlying system components.

Issues of Note:

See photos above

Summary and Recommendations:

An APP roof is a very durable roof system. With diligent maintenance, and addressing the noted issues above, the owner should expect at least another 10 years of service from this roof system.

Inspected on Nov 12, 2013 by Greg Krushel, T.Q.
Inter-Provincial Trade Qualification # J-23-24221 (July 1991)