ROOF REPORT 3130 TCHULAHOMA MEMPHIS, TENNESSEE BUILDING OWNER: Memphis Shelby County Airport Authority BUILDING MANAGER: MSCAA SURVEY DATE: 6/12/17 BUILDING CONSTRUCTION COMPLETED: 1985 ROOF AREA (SF): 200,000 WALLS: Precast concrete FRAMING: Steel DECK: 1 1/2" steel SLOPE (IN PER FT): 1/4± ROOF EDGE: Gravel guard east and west, very low parapet north and south ROOF ACCESS: Interior fixed ladder and roof hatch DRAINAGE SYSTEM: Gutters and downspouts to storm system OVERFLOW: N/A SPECIAL FEATURES: Metal canopy in various places on west side. (Photo 1, not inspected) ROOF SYSTEM COMPLETED: Unknown, estimated 2001 ROOFER: Unknown COMPOSITION: Emulsion coating, 3-ply built-up (PPR), wood fiber cover board (damp where cored), 1.75 polyisocyanurate insulation, total thickness 2-5/8 WARRANTY: N/A BIGHAM ROOF CONSULTING 9160 Hwy 64, Ste 12 PMB 135, Lakeland, TN 38002-8094 (901)606-8254 fax (901)205-1963 jbigham@bighamroof.com
CONDITION GENERAL CONDITION: Poor. There are numerous splits, mostly in the South Section. (Photo 2) Most have been patched (Photo 3), but in some cases, the splits have lengthened past the patches (Photo 4), and in many other cases, the patches have split. (Photo 5) Much of the emulsion coating has worn away, and in many places the asphalt coating on the felts has eroded exposing the matt. (Photo 6) LEAK REPORTS: Leaks have been reported in the South and Center Sections. A large portion of the building is unoccupied, and some leaks may go unreported. The core sample taken in the south section was damp. SPECIFIC PROBLEMS: 1. Many of the gravel guards have been restriped in, but many of the repairs are failing and the other gravel guards need to be stripped in again. (Photo 7) 2. Most of the pipe penetrations are pitch pockets filled with roofing cement, and the cement is shrinking. (Photo 8) 3. Gutters are rusting. (Photo 10) Also, the gutters have no expansion joints and can be assumed to be leaking. (Photo 11) 4. The three sections of the roof are divided by area separation joints. The one between the South and Center Sections of the roof is covered by metal and could be maintained a while longer. (Photo 11) The one between the Center and North Sections of the roof is covered by a bellows type expansion joint cover and is damaged in a number of places. (Photo 12) 5. At least one of the air conditioning units discharges condensate onto the roof. (Photo 13) A continual supply of water on an asphalt based roof will deteriorate it. LIFE EXPECTANCY: South Section none, Center and North Sections 1 to 2 years. SUMMARY CONCLUSIONS: With many more splits, the South Section is in worse shape than the other two. Why is not clear. It may be older. With the air conditioning units there, it has had more traffic, but the area with the splits goes beyond where most of the traffic would have been. Regardless of the reason, the roof is at the end of its life and should be replaced. The South Section should be replaced immediately. The other two section could be repaired and maintained for another year or two, but it would cost less and be more practical to do all at once. Because there is only one roof, the roof can be overlaid with another roof system. Before doing so, an infrared moisture PAGE-2
scan should be performed to identify areas of wet insulation. All wet insulation should be removed before installing the new roof. If more than ten percent of the insulation is wet, tear all the roofing off down to the deck. RECOMMENDATIONS: 1. As with any commercial roof, clear it of debris quarterly or as experience dictates. This particular roof was fairly clean, but it would be a good idea to cut overhanging trees back. (Photo 14) 2. Have a roofer inspect it annually and make repairs as needed before they become leaks. 3. Perform an infrared scan of the roof and mark off areas of wet insulation. Replace wet insulation. If the area is greater than ten percent of the roof, tear off the entire roof down to the deck. 4. Install polyisocyanurate insulation, cover board and a modified bituminous roof. The roof can be expected to last 20 to 25 years. A less expensive alternative is a.060 TPO roof with polyisocyanurate insulation. It will cost about half as much and last half as long. It is also more easily punctured and can have a higher maintenance cost. 5. Replace gutters and downspouts. Gutters should include expansion joints. Replace all gravel guards and copings. 6. Pitch pockets should be avoided. If they are used, they should be filled with self-leveling (pourable) polyurethane sealant. 7. Pipe all condensate drains to sanitary sewer. -John T. Bigham, RA RRC CCS June 28, 2017 6-28-17 PAGE-3
NORTH SECTION AREA SEPARATION JOINT CENTER SECTION AREA SEPARATION JOINT SOUTH SECTION CORE SAMPLE ROOF HATCH AERIAL-1
Photo 1 Photo 2 Photo 3 PHOTOS-1
Photo 4 Photo 5 Photo 6 PHOTOS-2
Photo 7 Photo 8 Photo 9 PHOTOS-3
Photo 10 Photo 11 Photo 12 PHOTOS-4
Photo 13 Photo 14 PHOTOS-5