Attachment 2 RFI CLC Roof HVAC Piping Replacement 36C24426B0017.pdf

CLC Roof HVAC Piping Replacement

Project #460-26-008

36C24426B0017

RFI

1. Mechanical / Piping Replacement Limits: The Scope of Work requires replacement in kind of the Heating Hot Water (HHW) and Chilled Water (CHW) piping, including associated main and branch piping on the Community Living Center roof; however, the exact limits of replacement are not clearly shown. Please provide a marked-up as-built drawing, roof plan, or highlighted aerial/Google Earth image identifying the exact piping runs to be replaced for each system. The markup should identify, at a minimum, the starting and ending points, tie-in locations, branch piping included, approximate routing, pipe sizes, and any areas where piping is to remain. Please also confirm whether the stated quantities of approximately 300 LF of 3-inch CHW piping and 300 LF of 2-1/2-inch HHW piping are intended only as estimates or as the required bid quantities.

VA Response: Replacement limits begin and end at rooftop piping with tie-ins at the last roof isolation valve.

2. Mechanical / Piping Components and Accessories: Please clarify what is included in the requirement to “replace in kind” within the piping replacement limits. Specifically, please confirm whether the Contractor is to replace all valves, fittings, flanges/unions, strainers, drains, vents, gauges, thermometers, flexible connectors, dielectric fittings, specialties, pipe supports, anchors, guides, and other accessories located within the identified piping runs. If any existing valves, supports, or accessories are intended to remain and be reused, please identify those items. Also, please confirm whether existing isolation valves at the building/roof penetrations are expected to remain in service or be replaced as part of this project.

VA Response: Within the rooftop limits, replace in kind rooftop valves, fittings, unions/flanges, strainers, drains/vents, gauges/thermometers, dielectric fittings, specialties, and pipe supports where necessary.

3. Mechanical / Piping Materials and Joining Methods: The Scope of Work identifies approximately 3-inch carbon steel piping for the CHW system and 2-1/2-inch Type K copper piping for the HHW system. Please confirm the required piping specifications and joining methods for each system, including whether the carbon steel piping is to be welded, grooved, or otherwise joined, and whether the Type K copper is to be brazed, soldered, or joined by an approved mechanical system.

Please also confirm that all branch piping is to match the existing pipe material and size in kind, and identify any required corrosion protection, dielectric separation, exterior coatings, or special requirements for rooftop installation.

VA Response: All lines are Carbon Steel.

4. Mechanical / Testing, Flushing, Treatment, and System Restoration: Please clarify all testing and system-restoration requirements that are to be included in the base bid after the new piping is installed. Please confirm whether the Contractor is responsible for hydrostatic/pressure testing, flushing and cleaning, chemical treatment, glycol or water treatment, filling, venting, leak testing, startup, balancing, and final verification of both the HHW and CHW systems. If chemical treatment or glycol is required, please identify the required concentration/product criteria and whether the VA will provide existing system-treatment information. Please also identify any required test pressures, test durations, reports, water-quality testing, TAB work, or commissioning documentation that must be submitted before the systems are returned to service.

VA Response: Items highlighted in GREEN are required to be performed by the contractor. Test pressure is 1.5 times operating pressure.

5. Shutdowns / Phasing / Temporary Service: The solicitation requires the Prime Contractor to phase the work to minimize downtime to the areas served by the affected systems. Please identify the maximum allowable shutdown duration for the HHW and CHW systems and the minimum advance notice required for each shutdown. Please clarify whether multiple shutdowns/phases will be permitted and whether the VA has preferred sequencing for the CLC and Physical Therapy/West Entrance areas. Please also confirm whether temporary heating, temporary cooling, bypass piping, or other temporary service will be required during construction.

Finally, please clarify whether the VA or the Contractor will be responsible for system isolation, valve operation, draining, refilling, venting, and final return to service.

VA Response: One week notice for shutdowns. Chilled water piping will be shutdown and drained for season after 11/1. If work is to be done on HHW loop during season, then temporary bypass line will be required to keep heating loop operational.

6. Electrical / Heat Trace System and Controls: The Scope of Work requires replacement of the electric heat trace on both piping systems. Please provide the required heat trace design criteria, including manufacturer/type, watts per foot, voltage, number of heat trace runs per pipe, circuit lengths, insulation assumptions, ambient/design temperature, control method, and any monitoring or alarm requirements. Please also clarify the Government's preferred control arrangement:

(1) one centralized multi-circuit heat trace control panel with individual circuit control/monitoring for all new rooftop piping, or (2) individual thermostats/controllers for each piping run or circuit. If a centralized panel is desired, please identify the preferred panel location and available power source.

Please also confirm whether existing branch circuits, feeders, disconnects, conduit, and controls are to be reused or replaced, and provide available panel schedules/circuit information.

VA Response: Replace electric heat trace on both systems. Manufacturer/Type- EasyHeat, Cable Type-SR Trace Self-Regulating, Pre-Terminated Heating Cable, 8 watts per foot at 50F/10C, 120V, EasyHeat C4XC Thermostat.

7. Insulation and Exterior Weather Protection: The Scope of Work requires replacement of piping insulation in accordance with Specification 23 07 11, Section

2.5. Please provide the applicable specification and confirm the required insulation material and thickness for both the CHW and HHW piping. Please also identify the required vapor barrier, exterior weatherproof jacket, jacketing material/thickness, fitting and valve covers, sealants, termination details, and UV/weather protection required for rooftop service. For CHW piping, please confirm the required continuous vapor-barrier treatment at fittings, valves, supports, and penetrations.

Please also clarify whether removable insulation covers are required at valves, unions, flanges, strainers, or other serviceable components.

VA Response: Provide insulation per VA Spec 23 07 11 Section 2.5 with a secondary vapor barrier for all pipe diameters and exterior weatherproof jacketing suitable for rooftop service. For CHW, ensure continuous vapor-barrier treatment at fittings, valves, supports, and penetrations. Provide removable covers at serviceable components (valves/unions/flanges/strainers).

8. Roof / Pipe Supports / Penetrations: Please clarify the required scope for the existing rooftop pipe support system. Are existing supports, sleepers, stanchions, anchors, guides, and support frames to be reused where serviceable, modified to accommodate the new piping, or replaced in their entirety? Please identify any required spacing, load, or support-system standard that should be used for pricing.

Please also confirm whether the work includes any new roof penetrations, curbs, flashing, roofing patching/repairs, roof protection pads, or waterproofing associated with the piping replacement. If roof penetrations or roofing repairs are anticipated, please identify the existing roof type and any manufacturer/warranty requirements that must be maintained.

VA Response: Reuse existing roof supports where serviceable and compliant, subject to contractor field verification and VA approval. If penetrations are required, restore flashing and waterproofing to maintain roof warranty.

9. Demolition / Existing Conditions / Hazardous Materials: Please confirm the extent of demolition required for the failed piping systems, including whether all existing failed piping, insulation, heat trace, supports, electrical components, and associated debris within the replacement limits are to be completely removed from the site. Has the existing piping insulation, mastics, coatings, sealants, or other materials in the work area been surveyed or tested for asbestos, lead, or other hazardous materials? If testing has been completed, please provide the available reports. If hazardous materials are encountered that were not identified in the bid documents, please confirm that abatement/remediation will be performed by the Government or handled as a contract change rather than included in the base bid.

VA Response: Remove failed rooftop piping, insulation, heat trace, supports, and associated debris within the replacement limits per Construction Waste Management (01 74 19). Project was installed within the past 10 years. There is NO ACM located in the area. IF ACM were detected remediation would be via the change order process.

10. Work Hours / Off-Hours Requirements: The Scope of Work states that the Contractor shall plan to perform all work outside the hours of 0800-1600 Monday through Friday, while the solicitation's general provisions list normal Contractor work hours as 0700-1630 Monday through Friday and state that off-hours work may be required. Please confirm the work schedule that bidders should carry in their base price. Specifically, please confirm whether all demolition, piping, insulation, heat trace, testing, and related work must be performed outside 0800-1600, or whether certain activities may be performed during normal daytime hours. Please also confirm whether night and weekend work is permitted without additional Government restrictions and whether any work must be specifically scheduled around patient-care operations.

VA Response: All work shall be performed outside 0800-1600 Monday-Friday in the hospital environment.

11. Superintendent / Prime Contractor Onsite Representation: Please confirm whether a full-time onsite Superintendent is required for the duration of active construction. FAR 52.236-6 and the VA production-report requirements reference Contractor superintendence and daily reports signed by the Contractor superintendent. If a Superintendent is required, please clarify whether that individual must be a direct W-2 employee of the Prime Contractor or whether a qualified employee of a subcontractor may serve as Superintendent/onsite representative. Please also confirm whether the Superintendent must remain onsite whenever any subcontractor is working, including nights and weekends, and identify any minimum experience, OSHA training, or other qualification requirements for this position.

VA Response: Contractor shall provide a full-time onsite Superintendent during active construction and whenever subcontractors are working. Direct employee of the Prime Contractor.

12. Site Safety and Health Officer (SSHO) / Competent Person: Please confirm whether this project requires a dedicated Site Safety and Health Officer (SSHO) in addition to the OSHA-certified Competent Person identified in the solicitation. If an SSHO is required, please provide the minimum qualifications, training, experience, and required onsite presence. Please also confirm whether the Superintendent may serve concurrently as the SSHO and/or Competent Person if the individual meets all qualifications. The solicitation states that the General Contractor's Competent Person must have OSHA 30-hour construction training and maintain a presence whenever the General Contractor or subcontractors are onsite; please confirm whether this requirement applies during all night and weekend work as well.

VA Response: Provide an OSHA-30 Competent Person presence whenever work is ongoing. An SSHO may be required depending on the safety plan; combined roles are acceptable if one individual meets all qualifications and onsite presence requirements. Compliance with OSHA 29 CFR 1910/1926 and VA EOSH is mandatory.

13. Quality Control Manager / Combined Roles: Please confirm whether a dedicated Quality Control Manager (QCM/QAC) or formal Contractor Quality Control program is required for this project. If required, please identify the minimum qualifications, required submittals/plans, inspection or testing responsibilities, and required onsite presence for the QCM/QAC. Please also confirm whether the Superintendent may serve concurrently as the QCM/QAC, SSHO, and Competent Person if one individual meets all required qualifications, or whether any of these positions must be staffed by separate personnel. If a formal three-phase control process, preparatory/initial/follow-up meetings, daily QC reports, or other USACE-style quality-control procedures are required, please identify those requirements so bidders can include the appropriate staffing and administrative costs.

VA Response: Contractor must implement VA-standard construction quality control. A dedicated QCM/QAC may be required; combined roles with Superintendent/SSHO/Competent Person may be acceptable if qualifications meet all requirements. Submit QC plans and daily reports per VA procedures.

14. First question was about the confusion of amount of piping VA Response: See above. They should have taken it off during the pre bid.

15. Will there be a set of drawings sent? And more clarity on the starting point of the pipe?

VA Response: Yes. VA will provide AutoCAD background drawings upon request;

contractor must field-verify all dimensions and routing. Start/stop points are rooftop piping terminating at the last roof isolation valves.

16. As of now I believe the engineer who walked us around said just the roof piping to the unit?

VA Response: Yes. Roof piping to the unit.

17. Can the saddles or insulation be reused? Valves?

VA Response: Replaced.

18. Heat tape fixed or replaced?

VA Response: Replaced.

19. A staging area is set. I was told it was ok to put a roll off dumpster on site?

VA Response: A roll of dumpster is permitted in the designated staging area subject to coordinate with the VA Engineering and in compliance with Specification 01 74 19.

20. Are after hours or weekends available?

VA Response: No.

21. We couldn’t clearly identify what piping needs to be replaced. Does the VA have a drawing that shows what piping is to be replaced – a clear start and end point for the piping?

VA Response: VA will provide AutoCAD backgrounds; contractor must field-verify rooftop piping routes and start/stop points.

22. Is it the VA’s intent to connect to the last valve on the roof of the CLC or is there work in the mechanical room as well?

VA Response: Connect at the last isolation valves; work is limited to roof piping and does not extend into the mechanical room.

23. Does the VA have a specific fall protection approach in mind or is that up to the prime contractor to determine?

VA Response: Fall protection is contractor means and methods; comply with OSHA and VA EOSH requirements.

24. Please confirm that all 4 pipes on the roof shall be replaced.

VA Response: Yes. Replace CHWS, CHWR, HHWS, and HHWR rooftop piping.

25. Please confirm both the chilled water supply & return, and the hot water supply & return should be replaced. This would be 4 pipes.

VA Response: Yes. Both CHW supply/return and HHW supply/return shall be replaced.

26. Please confirm if the VA will handle draining the system prior to contractor work.

VA Response: Yes.

27. Please confirm existing roof supports are to be re-used.

VA Response: Reuse existing roof supports where serviceable and compliant, subject to field verification and VA approval.

28. Please confirm there is glycol present in the system.

VA Response: No glycol present.

29. The solicitation calls for as-built drawings but none were provided. Will the VA provide a set of CAD drawings for us to update with as as-builts?

VA Response: Yes. VA will provide AutoCAD backgrounds upon request, and contractor shall deliver final CAD-format as-builts within 30 days of completion.

30. Per RFI 58 it seems like there is concrete deck, too. Please confirm which roof areas have existing concrete deck and which ones have steel deck.

VA Response: Contractor must field verify and coordinate findings with VA Engineering.

31. New specs provided call for substrate board and OSB, please confirm that none of these are required.

VA Response: Substrate board and OSB are not part of the piping replacement scope.

32. Elevate LS-FR Low-Slope Fire Retardant white roofing EPDM is not available in white, is a different color acceptable?

VA Response: Roof membrane replacement or color selection is not included in this project.