Scope of Work V3.pdf

B571 Partial Roof Replacement Naval Submarine Base New London, Groton, CT

SCOPE OF WORK

A. General Information: B571 is an approximately 12,000 sf building located on the bank of Thames river. The building functions as the Nautilus Museum and Library. The museum building was originally built in 1984-85. An addition to the museum was constructed in 2000-2001 that added an auditorium and a library to this building. The building has gone through various minor repairs over the years.

B. Existing Building Conditions: The overall building condition is good, but roof leaks have been an issue. Several roof repairs have been performed by PW to resolve the water leak in the building. It appears that the source of the roof leak is at the top of the walls at high and low parapet walls around the ballasted EPDM roof. The building has several levels of roofs. The museum area has a fully adhered EPDM roof - replaced in 2006 with 15 year warranty and it is in good condition. The Library roof is also fully adhered EPDM roof. This roof has a few areas with patches of repairs. It appears to be original roof. The roofing over all the mechanical areas except for one area, is ballasted EPDM. Due to a lot of maintenance traffic, this roof seems to be in poor shape. This roof was replaced a few years ago and has a single layer of EDPM. There appears to be enough clearance to replace the roof without hoisting the roof top units. (See photo below.)

Many of the current infiltrations are attributed to the various deficiencies within the existing; metal coping joints, or the coping to building envelope connections, the metal through wall scuppers, the poorly sloped head flashings along the glazed skylight system, as well as from locations in which the existing EPDM membrane is surface mounted to the vertical metal wall panel systems. An indicator that infiltrations are originating from elements above the roof can be found at the locations along the EPDM base walls (directly below these building envelope defects) in which large pockets of water are collecting (forming above the level of the existing Carlisle roof system These copings need to be replaced under this project.

There are some inactive and abandoned electrical conduits in the roof along the parapet walls.

B1 - Site: The building is located on a relatively level land on the bank of Thames River on the west side and a larger parking area on the North of the building. The roofs of this facility are at different levels and are accessed through a ladder through the building and ladders between the roofs.

B2 - Building Enclosure:

a) Exterior Walls: The exterior walls of the building are made up of metal studs and insulated metal panels.

b) Windows: Windows and curtain-wall throughout the building are aluminum tube frame with insulated glass.

c) Roofing: The building has single ply EPDM roofing throughout the museum building and the library building.

B3 - Hazardous Materials: Hazardous materials survey related to roofing is performed and provided as a separate document.

C. Objectives: The objective is to repair defective roof areas and details and extend the functional life span of the roofs either by replacing the roof or by restoring the roof.

D. Scope of Work: The scope of work for this project is limited to roof replacement/ roof repairs and roof restoration. Remove all abandoned and inactive electrical conduits on the roof. Consult with the customer before removing these conduits.

D1 - Replacement of Roof: Remove all ballasted roofs and the small roof along the water’s edge with periscope penetration. Where the roof is being replaced, the scope of work includes removal of existing roofing down to the roof deck and at least 10” up the wall all around. Remove and dispose of ballast and walk pads. Replace roof with Fully-adhered EPDM roof as specified with additional insulation. Mechanically terminate the EPDM roofing to existing EPDM on the walls with continuous termination bar and sealant. Existing EPDM on vertical walls shall remain in place.

Modify parapet/coping and roof drain details as necessary to accommodate additional insulation and ¼”-1’-0” slope in the roof to facilitate adequate draining of storm-water. Roofing system must be rated for the local wind speed.

The copings at all ballasted roofs seem to be the culprit for water intrusion in the building. Fully cover all high wall tops with EPDM membrane and secure with new pre-manufactured metal fascia system with continuous cleat per the manufacturer’s recommended details. At the mechanical wells, remove existing ballasted roofing, insulation and replace insulation to match existing insulation thickness (6”), taper insulation to at least ¼” per 1’-0” slope to drain. Replace and Re-flash roof drains. Re-flash through wall scuppers.

Approximately 3,300SF

D2 - Evaluation and Repair of Roofs: For the Library area roofing and small roofs (except one with Periscope penetration, which will be replaced with other ballasted roofs), conduct an infrared scan to locate wet/moist areas if any. Remove wet/moist insulation and roofing assembly down to the metal deck, replace with new roofing assembly to match existing surrounding roofing assembly and patch those areas watertight. Clean entire roof area of all debris and plant growth as recommended by the manufacturer and apply restoration coatings. Repair and reseal all the copings and make them watertight.

In the areas in which the existing roof membrane is surface mounted to the existing vertical metal wall panels, install new 2-piece Stainless Steel Receiver Apron over new T-bar reset pm water cut-off/ Dutch clips. Apply new sealants at metal panels’ joints above surface applied existing vertical flashing. Secure all copings with cap sheet, fastened cleat and a drip edge.

Head flashing at the main entry curtain wall shall be replaced and terminated at the roof coping with matching metal color profiles “Dove Gray”.

Approximately 5,200SF

D3 - Resealing of Roof: For Museum roof, inspect the roof for any open seams, holes or any other deficiencies. Repair and reseal all the seams, flashings and penetrations. See attached aerial view of the roof showing scope of work.

Approximately 4,550SF

D4 - Recoating of Roof: Recoat the repaired roofs and resealed roof with fluid applied coating with 15 year warranty.

D5 – Duration: 120 days from award

PHOTO OF TYPICAL MECHANICAL WELL

Photo shows fully adhered EPDM on walls around mechanical wells to remain. Remove any water accumulation at the bottom of the wall and reseal.

E. Add Option: Fluid applied roofing membrane coating over existing roofing areas to be scanned and repaired (approx. 9,654SF), as noted in keynotes 2 and 3 on Drawing A103 – Plan & Keynotes V2.