FA252119BA014_-_RFI_Response_and_Add'l_Info.pdf

DBEH 18-1547, RPR ENVELOPE, FAC 1645

SOLICITATION NO.: FA252119BA014

RFI RESPONSE, ADDITIONAL INFORMATION/INSTRUCTION – JUNE 20, 2019

RFI RESPONSE:

1) Will a CADD version of the as-built drawings be required? Did not see anything mentioned in spec section 01 78 00.

ANSWER: No. Contractor is to provide electronic, Adobe, pdf, redlined marked-up drawings. The drawings will show all deviations from the bid documents and will clearly be labeled As-Built on all sheets and include the contactors name and contact on the front page. All markings shall be in red.

2) Drawings Sheet AD-100 Flag Note 35 states the Roof J roofing assembly is to remain, but Sheet A-100 Flag Note 35 states to provide and install new roofing system at Roof J. Please clarify.

ANSWER: Roof J has a single ply membrane and metal deck. New roof membrane will be a mechanically fasten, two-ply membrane overlay system, reference Sheet A-505, two lower details.

3) Drawing E-100 Flag Note 7 states to install 2 salvaged light fixtures. The SOW states to dispose of them. Please clarify.

ANSWER: The light at the top of the access stairs is to be removed and disposed. The light at the south side of Roof I is to be disconnected and reinstalled.

4) Drawing E-100 Flag Note 18 states to ground the water service backflow preventer to the new grounding bus in the mechanical room. Would it be acceptable to drive a grounding rod near the backflow preventer to ground this?

ANSWER: Yes, however, an existing lighting protection down conductor is present and within 10 feet of the water service backflow preventer. Contractor is to connect backflow preventer and down conductor/ground rod at or beneath ground surface per Flag Note #18 Sheet E-101.

5) Drawing Sheet SPA-601, Typical Door and Frame Note 7 states HM doors shall be 18 gauge. Our door subcontractor suggests that given the location for these doors, they should be 16 gauge A60 galvanized doors to withstand the weather. Please advise if the Government wants a thicker metal for the doors.

ANSWER: Doors shall be fabricated of 18 gauge sheet metal. Additionally, In lieu of the specified factory rust inhibiting primer, the GC shall provide the following finish as a minimum:

Hot-Dip Zinc-Coated and Factory-Primed Finish Fabricate exterior doors and frames from hot dipped zinc coated steel, alloyed type, that complies with ASTM A924/A924M and ASTM A653/A653M. The coating weight must meet or exceed the minimum requirements for coatings having 0.4 ounces per square foot, total both sides, i.e., A40ZF120. Repair damaged zinc-coated surfaces by the application of zinc dust paint. Thoroughly clean and chemically treat to insure maximum paint adhesion. Factory prime as specified in SDI/DOOR A250.8. References:

ASTM A924/A924M (2018), Standard Specification for General Requirements for Steel Sheet, Metallic-Coated by the Hot-Dip Process

ASTM A653/A653M (2017), Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy- Coated (Galvannealed) by the Hot-Dip Process

SDI/DOOR A250.8 (2003; R2008), Recommended Specifications for Standard Steel Doors and Frames

6) The SOW states the HVAC package unit to be a 12.5 ton, but the plan note #5 on page AD-100 states it to be a 15 ton package unit. Which is the correct tonnage of HVAC package unit is desired?

ANSWER: The HVAC package shall be 12.5 ton per the SOW. Also, follow all other specification given in the SOW.

7) ROOF C: Can the existing grating at the viewing platform level be removed and stored on the existing steel structure framing / existing roof during reroofing? If not, advise expected means and methods for grating storage.

ANSWER: Yes, absolutely, the removal and replacement of the steel grating is one of many challenges this project presents. The government intends to partner with the contractor and support their efforts at every opportunity.

8) ROOF D: Please review and advise if the railing to be removed and replaced at the top of the landing can be hot dip galvanized steel in lieu of 304 Stainless steel.

ANSWER: Yes hot dip galvanized steel in lieu of 304 Stainless steel is acceptable. Paint to match existing.

9) The existing duct supports that are shown to remain and be protected are currently just “sitting” on the gravel roof surface (see photo AD-901, Roof A, North View). If they are to remain and the roof slope will change/increase, how will these supports be attached to the new roof surface to comply with wind load? Should they be attached or simply

“float”? Regardless, it would appear that some modification to these supports will need to occur if they are to remain.

ANSWER: Thank you for this observation, in lieu of protecting and modifying the existing supports, contractor is to remove and dispose of existing supports and provide new supports that are adhered or attached to the concrete deck, and flashed at the roof surface. New supports may be pipe, tubing, angles, etc. and are to be corrosion resistant material such as painted hot dipped galvanized, aluminum, or stainless steel.

10) It is our understanding that the Building Code will require the HVAC unit to be 30” above the roof surface based on the width of the unit. If we are to comply with the Bldg. Code, the existing ductwork transitions will need to be replaced due to the disparity between the new/old elevations. If the ductwork transitions will be replaced, please provide direction on new insulation type/thickness? Exterior Jacketing type/thickness?

ANSWER: For bid, contractors are to assume the existing ductwork transitions are to be replaced. The new insulation type and thickness is to be similar to existing, 1.5” thick rigid insulation with a reinforced foil air and vapor barrier surface.

11) The new HVAC equipment stand is stated as being either aluminum or galvanized per Statement of Work, para.

5.c…Drawing A-100, Note 18 states Galvanized…Flag Note 8, APA-101 states Aluminum. Please clarify which is required?

ANSWER: HVAC equipment stand and stand legs are to be aluminum.

12) Please confirm that the roof structure is concrete where the new HVAC unit will be installed per the view shown as

Roof Profile Section 1, dwg, A-501?

ANSWER: Roof structure is cast-in-place concrete.

13) Does the existing HVAC stand or flashing contain any lead based paint or ACM materials?

ANSWER: The HVAC stand or flashing was not tested for lead base paint of ACM material. Given that, Flag Note #2, Sheet SPAD-101 should be followed.

14) Will the new HVAC unit support stand, which is to be signed by a Florida P.E., be required to show wind load attachment details? If so, will the actual wind load calculations be required to support the attachment details?

ANSWER: Actual wind load or engineer calculations will not be required. However the signed and sealed shop drawings will show all materials, details, dimensions, connections and attachments for the beams and legs of new

HVAC stand.

15) Please provide make and model of the existing HVAC unit?

ANSWER: TRANE, Model No.: WCH180B400EA; Serial No.: M41101730D; MFG Date: 10/1997.

ADDITIONAL INFORMATION/INSTRUCTION

1) CORRECTION: Flag Note 17, Sheet E-100, Replace Room 106 with Room 137.

2) ACCEPTABLE ALTERNATIVE: Where aluminum anodized finish is required, aluminum milled finish will be accepted.

3) CLARIFICATION: Flag Note 19, Sheet A-100, the 300 SF of coating is intended to be an amount sufficient to repair damage area from removing and replacing metal grating.

4) ACCEPTABLE ALTERNATIVE: In lieu of new spot welds to reattach grating on Roof C, approved mechanical fasteners similar to existing will be allowed.

5) CLARIFICATION AND ACCEPTABLE ALTERNATIVE: Reference Flag Note 15, Sheet A-100 and Detail 10, Sheet A-503.

“Existing In-Place Steel Brackets” are spaced at approximately 7 feet. New hand rails are required to meet OSHA

1910.29. As required to meet OSHA 1910.26, the contractor shall provide new guard rails, new supplemental supports and/or new supplemental wall mounts. Also, it will be acceptable to forgo use of / incorporation of “Existing In-Place

Steel Brackets” to support the new handrails.

6) CLARIFICATION: Nearly all roof decks are cast-in-place concrete except for the metal decks of Roofs I, Roof J, and Roof

K, and the lightweight gypsum panel deck of Roof D. It is not anticipated that any roofs will need significant deck repairs, however the contractor should anticipate and include some minor deck repairs, but no greater than 1% of each roof area.

7) CORRECTION: The existing Door #3 on Roof B has a cypher lock. This cypher lock will need to be removed from the existing door and reinstalled on the new door. Additionally, the locks of Door #1 & 2 shall be keyed to match the existing keys of Door 1 & 2.

8) CORRECTION: Reference Statement of Work, Paragraph 10, Submittals, and Contractor is to provide material submittal for doors, and door hardware.