01 May 1999
(2) Inspection Techniques. As indicated in each of the preceding Chapters, the specific
characteristics of each system define the inspection and maintenance techniques necessary. Periodic
visual inspections and debris removal are essential to all. Material manufacturers and trade associations
provide information on needed inspection and maintenance.
(a) Low-slope inspections done while the membrane is still wet from recent rain help locate
areas that are not draining well. Applying foot pressure can sometimes force air or water back out of laps,
seams, or blisters finding defects that would otherwise not be detected. Caution: Wet roofs are slippery,
especially metal, coated SPF, and single-ply membranes.
(b) Maintenance will require compatible repair materials and tools. Refer to Chapters 3-10
and references in Appendix A for materials and equipment required.
(c) Roofs that are still under warranty should have leak repairs made by manufacturer-
authorized contractors only. Emergency repairs to a warranted system can be done by anyone but must
be reported to the manufacturer shortly thereafter.
(d) All roofing systems are dependent upon inspection and maintenance to reach their
design life. It is clear that periodic inspection and preventative maintenance greatly increase the life
expectancy of roofing system and reduces life-cycle costs. Maintenance, inspection, and minor repairs
should cost somewhere between 2 and 5% of the replacement cost per year. This will vary with
accessibility to the site, details of the survey, and amount of maintenance needed.
12-2. BUILDING ELEMENTS.
(1) Drains. Roof drains should be recessed below the drainage plane of the roof. Drains must
be sized properly to carry away the designed water flow. The addition of new drains, especially in areas
where deflection has resulted in ponding, is sometimes feasible and more cost effective than resloping
the entire roof.
(2) Ponding. Correction of ponding is generally beyond the scope of a maintenance program.
However, the addition of crickets or filling in a low spot on a BUR with bitumen and aggregate might be
appropriate. Major slope correction will be done at the time of reroofing.
b. Low Sloped Roofs. Punctures and open seams/laps can result in water entry. Water should
drain away from laps and seams i.e., laps and seams should not buck water.
(1) Damaged Roofing. Broken and missing units should be replaced. While underlayment may
protect the building against water entry for some period of time, unprotected underlay will gradually
(2) Access. Permanent ladders and walkways will reduce foot traffic damage on tiled roofs.
d. Structural Considerations. Damage to the roof deck from leakage will endanger the structure.
When leaks are reported, or when moisture is discovered during a moisture survey, the deck should be
checked to see if rotting, corrosion, or softening has occurred.