Answers to Questions.pdf

1. Is the water tank beneath the roof fully enclosed or open? If open, is it possible to have the tank covered by the government or drained prior to re-roofing to reduce the chance of debris entering the tank?

A job walk was offered to potential bidders to assess current conditions. The water tank is fully enclosed with 500,000 gallons of potable water that will be drained prior to construction beginning. Any debris that enters the tank will be removed by the contractor.

2. Moisture migration into the roof structure and new roof system may be a concern if the water tank is open or the interior produces high levels of humidity. A gypsum fiber roof board (e.g. Securock or DensDeck) is not a viable roof cover board as it will soak up moisture and dissolve within several years of application. A vapor barrier or moisture permeable membrane underlayment would be recommended. Does the government require any moisture mitigation in the new roof assembly?

At this time moisture mitigation is not deemed necessary with plywood sheathing and Cement Roof Board.

3. Is the existing gravel re-usable by the government for landscaping on location or will the government want a cost for demolition and disposal in our proposal?

A roll off container will be provided by the BOP for disposal of roof gravel ONLY. All other demolition debris will be the responsibility of the contractor per Statement of Work: B., B1., f. - Contractor will clean ground and haul away all roof related trash daily.

4. Is there an existing asbestos and/or lead hazardous material assessment of the existing roof available for review?

The BOP does not have knowledge of Asbestos Containing Material (ACM) and/or lead hazardous material within this specific roof system. A report is not currently available for review.

5. RFP Scope of Work Item B.b requires repair to damaged plywood sheathing and fascia. For competitive bidding purposes, please provide a quantity allowance for repair so all bidders are pricing the same amount.

A job walk was offered to potential bidders to assess current conditions. The approximate allowance of sub layer wood sheathing that is damaged is estimated at 60% of the total roof area, this will not be able to be definitively determined until demolition of existing roof. The approximate allowance for 2x6 & 2x8 fascia that is damaged and will require replacement is estimated at 90% of upper and lower roof perimeters.

6. RFP Scope of Work Item B.c calls for a “1/2” HD secure rock” cover board. Please clarify whether government requires a ½” HD polyisocyanurate insulation cover board or a ½” Securock Brand (or equal) gypsum roof cover board. These are very different in price, composition, and weight.

The cover board described in the Statement of Work (SOW) B., B1., c. – “Install 1 layer of 1/2 HD Secure Rock" is a Cement Roof Board to be applied over the sheathing. Cover board will be like product and meet or exceed the following specifications: FM Approved, Complies with requirements of FM 4450 and FM 4470, Meet FM Class 1 Mold resistance per ASTM D3273 Score of 10. Installed product will be a like product with like warranty approved upon BOP review and acceptance.

7. RFP Scope of Work Item B.d calls for Mulehide TPO. Are other TPO brands or other thermoplastic single-ply systems acceptable for government review and acceptance?

Per the SOW B., B1., d. - Install new 60 mil Mulehide TPO Roof System Mechanically fastened with 2-3/8” seam plates with heat welded seams. Installed product will be a like product with like warranty approved upon BOP review and acceptance.