B11_QA__0002.docx

Questions/Answers SACN – Replacement of Headquarter Office VC HVAC 140P6023B0001

1. What are the requirements should ceiling tiles become damaged during performance of the contract and require replacement? It was felt that due to the age of the structure, exact replacements may be unavailable.

ANSWER: Refer to Division 1 specification section 3.8 A 1. b. The contractor is must repair damage caused by construction operations. Protect building contents, and its occupants during construction period. If damage were to occur to the Acoustical ceiling tile, the contractor would have to work with the COR to determine an acceptable replacement for damaged tiles. It may be possible to remove tiles from another area in the building to replace any damaged tiles. The new (replacement) tiles should be similar in size, material/composition and color but do not necessarily need to be an “exact match”. COR to determine which location in the building will be utilized to acquire tiles to replace damaged tiles.

2. Are all line sets to be replaced?

ANSWER: Yes, refer to the Flag notes on Sheets M3 (note 20) and sheet M1.

3. Installation of the unit to service the museum collections will be re-located into the ceiling of the restroom adjacent to that area. There are currently two low-voltage sensors (one for the lighting and another for the fire suppression system) in the work area that may need to be moved. Is that process a responsibility of the contractor?

ANSWER: Yes, refer to the flag notes on sheet E3 – all costs associated with maintaining the functionality the fire alarm system and lighting shall be included in your proposal.

4. Although I thought Mechanical Schedule M8 was pretty clear regarding systems requirements, it was requested that clarification of existing systems be provided with respect to brand name, model number, voltage, tonnage, and BTUs.

ANSWER: Mechanical Schedule M8 seemed to address what the requirements would be for the project quite well.

5. M7, Are the existing concrete pads acceptable (calls out 4” pad), or do we need to replace them?

ANSWER: The existing concrete pads for the equipment shall remain. There is no need to replace it. Use the existing concrete pad.

6. M7, Are the existing copper lines ok to reuse? If not, does the mechanical pipe supports over the walkway with piping need to be enclosed in an enclosure? If yes, what material.

ANSWER: The intent is to run the mechanical and electrical lines to the new condensing equipment exposed on Unistrut framework. No enclosures are shown, and are not required.

7. Archive Storage, is there an allowable time slot this room can be down while replacing the system?

ANSWER: The contractor will provide a schedule for approval. The NPS would accommodate a reasonable amount of downtime for work activities in the archival storage area and requires notification 3-days prior to performance of any work.

8. Per note 20 on dwg M3, it has us replacing all the refrigerant lines – can we flush out all the old R-22 oil and reuse the existing lines. If we need to replace the lines, it will add a lot of rework and associated costs.

ANSWER: Bid the project as drawn and specified for new refrigerant line sets.

9. Note 3 on drawing M1 states for us to fill in the below grade trench below the sidewalk, does this mean infill with concrete? We didn’t see any concrete replacement notes, so we need clarification on the required infill.

ANSWER: Trench will be abandoned and filled with sand.

10. Some of the furnaces have duct smoke detectors and there is no mention of this in the drawings and in at least 1 location there is a fire alarm sensor in the ceiling that we need to remove to install a new furnace. Do we need to carry costs in our proposal for the work associated with the existing fire alarm system?

ANSWER: The intention of the flag notes and general notes on the drawings is to capture all work associated with the fire alarm system to maintain the functionality of the fire alarm system. All costs associated with maintaining the functionality the fire alarm system shall be included in your proposal.

11. As we didn’t remove ceiling tiles at the site visit will the government include a budget for unforeseen conditions above ceilings such as sprinkler piping or other items that may need to be relocated to allow us to complete our work?

ANSWER: Any rework of existing systems shall be the responsibility of the contractor, including electrical, plumbing supply, wastewater plumbing, and fire suppression systems.

12. What is the spec on the “ATC” called out?

ANSWER: ATC is called out to be Removed, salvaged, and reinstalled. Any ATC to be replaced due to damage will have to be submitted to the COR for approval. (See question 1, as well).

13. Does the owner have extra ATC on hand and if so, how much?

ANSWER: The park does not have any attic stock of the existing ATC. (See questions 1 and 12, as well).

14. Plans call out “remove and reinstall base”, but I don’t see work that requires this base to be removed. Please verify this is a part of the scope of work.

ANSWER: A7 detail 1 wall type, the 2” Z channel and 2” rigid with 5/8” gypsum wall board are new work. Should the baseboard become damaged during removal, a replacement – similar in dimension, wood species and finish will be installed.

15. Toilet room 123 has some ceiling devices in the ceiling that is to be demoed. Are we to included costs for the removal and reinstallation of these devices?

ANSWER: Any devices that are removed to complete the scope of work shall be reinstalled to provide all functional systems at completion. This includes work in toilet room 123. (See question 3, as well).

16. Is this contract considered to be a construction by special trade contractors or a general construction project.

ANSWER: NAICS is 238220 Heating and Plumbing and Air conditioning contractors. The prevailing wages shall be paid in accordance with the type of work being performed. Regarding the Limitations on Subcontracting Report, this is considered General Construction.

17. Section 21 04 00 1.2 states the entire building shall have fire protection sprinkler system installed. Please confirm if there is any fire protection work required in this project?

ANSWER: The specification noted for a fire sprinkler system shall be considered removed from the project documents. The existing fire sprinkler system shall be modified only as required for the installation of the new HVAC system. Any modifications to the fire sprinkler system shall be done in accordance with all applicable codes and regulations.