Project Information:

This building has three types of roofs:

•  Ballasted EPDM roof system
•  Asphalt impregnated mineral surfaced shingles
•  Asphalt built-up roofs

An outside consulting engineering firm performed a condition assessment of all ballasted EPDM roof sectors. The report made by the consulting engineering firm is provided here for reference.

The scope of work below takes into consideration all observations made and conditions identified.

Scope of Work

1. Ballasted EPDM Roof Sectors (see Consultant's Report, Roof Plan, Sheet 1 of 3):

1.1. Repairs to Roof Sector D2 (Admin. Offices & Open Gallery - 2 nd Floor): This roof area is in serviceable condition. The insulation is wet under a portion of the roof at the east end of Roof-D2. The openings that allowed the water to enter have been repaired. The exposed membrane at the parapet walls and at the base flashings of the walls have been coated with a white acrylic coating and are in good condition. The roof access door threshold is very low. The lead-coated copper counter-flashings at the expansion joint base flashings and wall base flashings are in good condition. There is a pitch pan where the sealant has shrunk and may create an opening that could become a roof leak. There have been substantial repairs of the membrane flashings at the base of the wall of Roof-D2.

Roof-D2 may be restored to a watertight condition and provide an additional 5-10 years of service. The wet insulation should be removed and replaced to restore the insulating value of the system. The pitch pan should be cleaned, primed, and filled with a pourable sealer. Seal the plumbing vent stack.

1.2.  Repairs to Roof Sectors C1 & C2 (Upper Gallery – 3 rd Floor): These roof areas are in serviceable condition. The lead coated copper expansion joint cover is in good condition. The aging of the membrane and the movement of the metal under the membrane is causing the membrane to split at the laps in the metal edge gravel stop. There is a structural crack in the masonry wall at the west end of Roof-C1. The membrane flashings along the sheet metal gravel stop should be replaced. The crack in the masonry wall should be sealed.

1.3. Repairs to Roof Sector B1 (Stack Tower - 8 th Floor): This roof area is in serviceable condition. The insulation is wet under approximately one-half of one of the south side “wing” roof areas (third “wing” from the east). There were no openings evident that were allowing water to enter the system. The exposed membrane at the parapet walls and at the base flashings of the walls has been coated with a white acrylic coating. The coating does help to slow the aging process, but the membrane is still shrinking, which causes “bridging” at the base of the parapet walls due to lack of membrane securement. There have been multiple coping joint repairs. There is a hole in the membrane at an area divider and there have been multiple repairs of previous holes. There are two locations where the edge of the membrane flashings is loose. There been substantial repairs at the membrane flashings. At the counter-flashing at the end of a coping cover, different types of metal have been placed in contact with each other. This will accelerate the corrosion of the metals.

This roof area may be restored to a watertight condition and provide an additional 5-10 years of service. The wet insulation should be removed and replaced to restore the insulating value of the system. The parapet membrane flashings should be reconstructed to eliminate the ‘bridging”. The hole in the membrane and the loose edges of the membrane flashings should be repaired.

1.4. Replacement of Roof Sector A (Elevator Penthouse - 10 th Floor): This roof area has moisture under the entire membrane. The moisture may be from wind blown rain that entered the system where the metal edge was pulled up by the wind, or it may have entered the system at the deteriorated stripping ply of the metal edge perimeter before the repairs were completed. This roof area should be replaced.

2. Reading Room - Composition Shingle Roof Sectors (see Consultant's Report, Roof Plan, Sheet 2 of 3):

The Reading Room is located on the north side of the library. The roof consists of ten (10) dormers, which are separated by eleven (11) pitched gable-end roof sectors. The vertical sides of the dormers and the gable-end roof sectors are covered with composition shingles.

Replace the composition shingles on the dormer walls and steep slope sectors over the Reading Room roof sectors.

3.  Reading Room - Asphalt Built-Up Roof Sectors (see Consultant's Report, Roof Plan, Sheet 2 of 3):

Each of the ten dormers, located at the Reading Room roof, has a low-slope asphalt built-up type roof sector. These built-up roofs have reached the end of their serviceable life and need to be replaced.

NOTE: FOR FALL PROTECTION REQUIREMENTS, CONSULT WITH THE UNIVERSITY'S ENVIRONMENT HEALTH & SAFETY AT (919) 962-5507.

Walter Davis Library

Project Related Sites:

Project Location Map
University Plan Room Information
Campus Building Design Standards