B09_Amd_5_Q_A_0005.pdf

FWS – HVAC and Remediation at the Sabine NWR

Solicitation (RFP) Questions and Responses:

1. What year was the building built where the work is to be performed?

The building was built in 2009. HVAC rehabbed and storm repair work completed in 2021.

2. "Drawings of the existing buildings are available" Can the drawings be provided?

As-builts attached.

3. Is there information on the existing air/water barrier between the exterior cladding and sheathing? Such as possible pictures during construction and/or existing drawings indicating the air/water barrier installed?

Yes, there is an existing vapor barrier between exterior cladding and sheathing.

4. 1.2 States "Furthermore, the contractor is tasked with performing mold remediation services, which include conduction a comprehensive mold assessment, detection, and remediation within the interior of the building. Field investigations shall be execute as needed to evaluate and document current site conditions. All quantities and measurements must be validated by the contractor prior to the initiation of work."

QUESTION 04a - How will these discovered items be treated?

QUESTION 04b - Will they be treated as a modification to the contract? QUESTION 04c - Are we to price up assuming the worst scenario? Due to the amount of unknown pathogens contained within closed walls could drastically increase the cost proposal. Please advise if we are to price up solely the testing and assessment components along with the outlined pictures with the one

(1) wall and the one (1) box of 2x2 ceiling tiles?

a. Discovered items shall be treated as recommended by the licensed remediation professional based on the findings of the comprehensive mold assessment and testing. As stated in the SOW, the contractor is required to conduct detailed evaluations, including moisture and humidity assessments, air and surface sampling, and provide mitigation strategies for all identified contamination sources. Remediation methods—including containment, HEPA-filtered air scrubbing, and EPA-compliant removal—will be implemented in accordance with EPA and ANSI/IICRC standards.

b. No. The initial contract scope already includes pricing for initial testing, treatment/repairs, and final clearance testing, as outlined in the SOW. These actions are to be accounted for within the base proposal. However, if remediation needs go beyond the stated scope (i.e., one wall and one box of ceiling tiles), then any unforeseen conditions may be discussed with the Contracting Office.

c. No. The proposal should be based specifically on the remediation of one (1) wall and one

(1) box of 2x2 ceiling tiles, as referenced in the photos and project documentation. The initial pricing should cover testing and assessment components, as well as the limited scope of remediation described. If mold contamination is discovered beyond this area during the assessment, it may be addressed later through discussion with the Contracting Officer.

5. 2.1 - "The new system, consisting of a condensing unit and air handler, shall be a minimum a 2-stage, 18 SEER pre-charged heat pump with backup emergency electric heat and programmable thermostat controls. The system shall be able to maintain interior humidity levels between 30% - 50% RH." A 2-stage unit will unlikely be able to meet the required humidity levels and would need to be a variable speed unit. QUESTION: Would you accept a 2-stage unit with separate dehumidification system in lieu of variable speed?

The SOW does not explicitly require a variable speed unit but sets the minimum standard as a 2-stage, 18 SEER unit, with the performance requirement being the ability to maintain interior humidity levels between 30%–50% RH. Therefore, if a proposed 2-stage unit combined with a separate dehumidification system can demonstrably meet these humidity control requirements, it may be considered compliant with the SOW, subject to review and approval.

6. 2.1. F) "Contractor shall replace water-damaged ceiling tiles to match the existing style and specifications" QUESTION: Do you have the specifications of the existing ceiling tiles?

QUESTION: Is the client okay with the tiles not being an exact match as the existing tiles colors may have faded compared to the new tiles?

Yes. The existing ceiling tiles are USG RADAR™ Basic Acoustical Panels, with the following specifications: Finish: Flat White 050; Edge Detail: SLT (Shadowline Tapered); Class: A Fire Rating; Texture: Lightly Textured Panel

These specifications should be used as the basis of replacement.

7. 2.1 G) "Contractor shall supply a louvered door for the electrical closet. The dimensions of the louver shall be established based on airflow specifications" QUESTION: Is the intent of this for air return? This will cause the space to become a plenum rated due to it now being negatively pressured. The entire space would need to be rebuilt and sealed. All wiring would need to be changed and the electrical and other equipment would need to be moved to another location.

QUESTION: Is the intent of the louvered door for supply for the HVAC system?

The intent of the louvered door is not to convert the electrical closet into a plenum-rated space. Rather, it is to support passive airflow, primarily to assist in ventilating the space and support return air to the HVAC system if needed. This design feature also helps dissipate heat generated by electrical equipment, not to establish the room as a primary air handling or return zone.

Extensive modifications such as rebuilding and sealing the room to meet plenum standards, relocating equipment, or reconfiguring wiring are not required under the current scope. The contractor should size and install the louver appropriately to assist in maintaining airflow balance without inducing negative pressure that would trigger a plenum classification.

8. 2.1. E) "Contractor shall replace water-damaged insulation under ductwork with new batt insulation in the attic, ensuring R-value equal to existing. (Basis of Design: 40% of batt insulation replacement.) All of the insulation needs to be replaced as it is installed incorrectly. In an unconditioned attic the insulation should be either unfaced or have the paper face to the cold side which would be against the ceiling. The paper face of the insulation is facing up. The paper face is a vapor barrier and the way it is installed could lead to moisture and mold issues.

QUESTION: Please advise if 100% of the attic insulation is to be replaced and/or the remaining 60% to be flipped with paper face down?

The remaining 60% of batt insulation may be retained and reused, provided it is undamaged, but it must be correctly installed to comply with building code and moisture control best practices.

9. The SOW address some of the needs for insulation in the attic space but does not address the needs below. The building is a raised building and should have insulation, installed properly, underneath. What is the current insulation underneath the building? How is that insulation installed? Is there a vapor barrier? How will this area be addressed as it is not in the SOW but will critical to sealing the building to control humidity?

Batt insulation is visible underneath the building; however, the installation method and the presence of a vapor barrier are currently unknown. FWS will verify the condition and address If corrective measures are required.

10. 2.1. E) "Contractor shall replace water-damaged insulation under ductwork with new batt insulation in the attic, ensuring R-value equal to existing. (Basis of Design: 40% of batt insulation replacement.) SOW says ensuring R-Value equal to existing however newer building codes increase the R-Value of insulation in ceiling spaces. Will this need to equal existing or be replaced to meet building codes?

The insulation is to be replaced to match the existing R-value, not necessarily to meet newer or higher code-required R-values.

11. Will the building be occupied while work is performed?

No

12. Confirm if Kynar finish metal panel colors are pre-selected or to be approved via submittals. If so, what is the lead time for approval?

Approved via submittal. See specification section 013300.

13. Matching of existing tiles. The office with microbial growth has ceramic or porcelain tile installed as a base board. It is very likely that drywall removal in that area will run down to the floor. If the tile base is not able to be salvaged (breaks during removal) will we need to try and find a match or will vinyl rubber base be allowed?

If removal of the drywall results in damage to the existing tile base, please match the existing tile as closely as possible in material, color, and size. The intent is to maintain the aesthetic and material consistency of the space. In the event that an exact match is not feasible, the contractor shall submit available tile options for review and approval by the Contracting Officer’s Representative prior to installation.

14. Once mold evaluation is complete and the extend of the issue known, will COR allow for contractor recommendation that varies from SOW? For example, due to many of the questions / concerns outlined above, we see an approach to keeping the HVAC system in the attic space, although the attic would need to be sealed and would become a conditioned space. Please advise if this approach will be acceptable?

As noted in the Scope of Work, the project requires that the HVAC unit be relocated out of the attic and into the designated electrical closet. This direction was established to address long-term performance, maintenance accessibility, and moisture management concerns commonly associated with HVAC installations in unconditioned attic spaces.

15. In executing this project, can one superintendent fulfill the supervision, safety, and QAQC roles?

Yes, provided the individual possesses the necessary qualifications and capabilities to manage all these responsibilities. It falls on the contractor to guarantee that sufficient time and resources are allocated to each area to uphold standards of quality and safety. These qualifications should be evident and documented in the superintendent's work history.

16. Are contractors required to issue a contract specific QA/QC Plan?

Yes

17. Are contractors required to issue a contract specific Safety Plan?

18. Is this project tax exempt?

19. We think the humidity issues will still persist after construction of new equipment is completed.

Would the FWS want to add to the sow to fix the humidity issues?

FWS will verify the condition and address If corrective measures are required.

20. Can that the room (diffusers for the HVAC system) be cleaned and reused instead of being replacing?

Yes, the diffusers for the HVAC system can be cleaned and reused if they are in good condition.

However, if there is any presence of mold or visible contamination that cannot be fully removed, the diffusers should be replaced to ensure air quality and safety.

21. What type of switch is required to activate/start the fans?

A thermostat or humidistat switch, or a combination of both.

22. Please provide original construction drawings so we can size the duct for the new unit.

As-built PDF attached.

23. Are the attic fans to be replaced?

Yes.

24. Is temporary cooling required for this project?

No, temporary cooling is not specifically required under the current SOW. However, if cooling is necessary to maintain indoor humidity levels during mold remediation, prevent further microbial growth, or ensure safe working conditions, then the contractor may need to propose temporary environmental controls as part of their execution plan.

25. Can we request additional site visit for contractor?

Yes, a second site visit is scheduled via this Amendment

26. Is it possible to reposition the new air handing unit in the same room but closer to the interior wall to allow clearance from the roofline to accommodate the duct work?

Yes, it is possible to reposition the new air handling unit (AHU) within the same room to improve duct clearance and accommodate roofline constraints. However, coordination with the existing electrical panel and data cabinet is required to ensure proper spacing, code compliance, and service accessibility. A drawing of the proposed AHU location must be submitted for review and approval during the product data (submittal) review process.

27. If we put the air handling unit in the utility closet, can we reroute the line sets underneath the building up into the bottom?

Yes, rerouting the line sets underneath the building and up into the bottom of the unit is acceptable. However, all penetrations and openings created by rerouting the lines must be properly sealed to prevent moisture intrusion, air leaks, and pest access, in accordance with standard building practices and applicable codes.

28. Can we submit equipment/material for prior approval before proposal is turned in?

No

29. Does the FWS require any calculations or documentation for the following items in the statement of work:

a. Duct Sizing

b. Humidity in each room No

c. Drains No, not for condensate drains. Follow manufacture recommendation.

d. Plumbing and electrical connections No. Follow manufacture recommendation.

e. Exhaust Fans Yes, product data and sizing related data

f. Batt Insulation Provide product data.

g. Ceiling tiles Provide product data.

h. Louvered doors Provide product data. If need for return, provide calculation.

i. Mold Containment and Remediation Yes, provide all reports and documentations.

j. Mold Removal and Surface Cleaning Yes, provide all reports and documentations. Provide product data.

k. Structural Drying and Moisture Control Provide report and documentation, Test and Balance Report.