S06 - 556-23-104 Amendment 0007_Attachment.pdf

AMENDMENT 0007

Project: Captain James A. Lovell Federal Health Care Center

Chilled Water from B188 to B3

To: Sean Brewner

Re: Bidder Questions

Amendment Number: 0007

From: Jonathan Carr, AIA

Date: 03/28/2025

VA | AE Project Number: 556-23-104 | 22018

Contract Task: 36C25219D0022 | 36C25223N0287

Specification Section: 23 07 11 Paragraph: See Below Drawing Reference: MP101, MP103, MP401 & MP501 Detail: N/A

Description: Amendment 0007 is issued in response to bidder questions. Amendment 007 contains specification and drawing revisions. Revisions are as follows.

I. Specification revisions are as follows:

Item 1: Spec Section 23 07 11, part 1.6.D. After the entry for “ASTM E136-2019,” add the following:

C534-2017... ........... Standard Specification for Preformed Flexible

Elastomeric Cellular Thermal Insulation in Sheet and

Tubular Form

C552-2007 ............. Standard Specification for Cellular Glass Thermal

Insulation

C1126-2019 ............. Standard Specification for Faced or Unfaced Rigid

Cellular Phenolic Thermal Insulation

D1248-2018 ............. Standard Specification for Polyethylene Plastics

Extrusion Materials for Wire and Cable

Item 2: Spec Section 23 07 11, part 1.6. After 1.6.G, add the following:

H. American Society of Mechanical Engineers/American National Standards

Institute:

ASME/ANSI B31.1-2024…Power Piping

Item 3: Spec Section 23 07 11, part 2.2. Delete “2.2 - Not Used” and replace with the following:

2.2 RIGID CELLULAR PHENOLIC FOAM

A. Preformed (molded) pipe insulation, ASTM C1126, type III, grade 1, k =

0.021(0.15) at 10 degrees C (50 degrees F), for use at temperatures up to 121 degrees C (250 degrees F) with all service vapor retarder jacket with polyvinyl chloride pre-molded fitting covering in utility tunnel / crawl spaces.

Item 4: Spec Section 23 07 11, part 2.3, Cellular Glass Closed Cell. After part

2.3.B, add the following:

C. Provide with aluminum jacketing in the utility tunnel / crawl spaces. Provide with all-service jacket in Building 188 and its adjacent corridor, plus an additional aluminum jacket for pipe protection, where shown. See Drawing

MP401.

Item 5: Spec Section 23 07 11, part 2.6. Delete “2.6 - Not Used” and replace with the following:

2.6 FLEXIBLE ELASTOMERIC CELLULAR THERMAL

ASTM C177, C518, k = 0.039 (0.27) at 24 degrees C (75 degrees F), flame spread not over 25, smoke developed not over 50, for temperatures from minus

4 degrees C (40 degrees F) to 93 degrees C (200 degrees F). Provide aluminum jacketing in utility tunnel / crawl spaces.

Item 6: Spec Section 23 07 11, part 2.7. Delete the phrase “…Section 32 21 13 for carrier specification.” Replace the deleted phrase with the following:

“…Section 23 21 13 HYDRONIC PIPING for carrier pipe specifications.”

Item 7: Spec Section 23 07 11, part 2.7. After part 2.7.D, add the following:

E. The system design shall be in strict conformance with ASME/ANSI B31.1, latest edition, and stamped by a registered professional engineer.

F. Install an aluminum diffusion barrier wrapping the closed cell foam insulation to prevent cell gases from dissipating out of the insulation.

G. Accessories:

1. End seals, gland seals, internal moment guides, fittings (tees and elbows), and anchors shall be designed and factory fabricated to prevent the intrusion of moisture into the system during shipping, outdoor storage, installation, and operation. End caps at the ends of the service pipe are required to prevent debris from entering the pipe for the period until installation.

H. Insulation Checks:

1. To ensure no voids are present, all insulation shall be inspected by one of the following two methods: 1) visually checked prior to application of the protective jacket; or 2) infrared inspection of the entire length during the foaming process. After successful completion of testing, all test report documents shall be submitted to VA-COR for records.

I. HDPE Jackets:

1. All straight sections of the factory pre-insulated piping system shall be jacketed with a High-Density Polyethylene jacket conforming to ASTM D1248.

PVC jackets shall not be allowed.

2. All fittings of the factory pre-insulated piping system shall be jacketed with the same material used for the straight sections of pipe and prefabricated to minimize field joints. Fittings shall be jacketed using a molded HDPE cover over polyurethane foam. Fittings shall be waterproof from the factory without the use of any type of tape, cellophane (or other non-HDPE plastic) wrap, mastic, glue, or hot air welds.

J. Field Joints:

1. All field joints shall be made in straight sections of pipe. Field joints other than at straight sections shall not be acceptable.

2. The method of field joint closure is as follows:

a. The field joints are pressure tested and inspected for leaks.

b. A split sleeve with holes in the top is placed around the joint area and secured with straps and sealed to the jacket with tape.

c. Two-part polyurethane foam is mixed properly and poured into the holes on the top of the split sleeve.

d. After the foam insulation has expanded and cured, any excess foam shall be removed.

e. An adhesive backed heat shrinkable sleeve is then placed around the field joint area making sure to overlap the sleeve onto the HDPE jacketing by at least 3” on each side. This 3” overlap is to be completely on the HDPE and does not include the length of overlap of the split sleeve or tape.

f. Heat is applied using a rosebud torch to the heat shrinkable sleeve slowly and evenly across the length of the sleeve until the sleeve has drawn tight.

g. Any spots that pucker up during the shrinking process shall be covered with a thick-bodied, asphaltic mastic (black roofing compound).

h. Backfilling of the trench shall not begin until the area has cooled to the touch.

3. The piping systems manufacturer shall furnish all the foam insulation, split sleeves, and heat shrinkable jacketing materials for making the field joints.

The contractor shall furnish the straps, tape, knives, saws, torch, gas, and mastic materials.

4. Extend a 12-inch length of bare, uninsulated, pre-insulated pipe and 4-inches of its pre-insulation and jacketing above grade or beyond retaining walls, for welding to the field-insulated pipe. Always maintain continuous pipe insulation across field-insulated and pre-insulated pipe joints, including through cored retaining walls and slabs. Tightly abut differing insulation types and lap-seal the field-applied vapor barrier and jacketing a minimum of 4-inches over the HDPE jacket. Whenever possible, do not bury the field-applied insulation, vapor barrier, and jacketing.

Item 8: Spec Section 23 07 11, part 2.9, Insulation Facings and Jackets. After

2.9.F, add the following:

G. Aluminum Jacket-Piping systems: ASTM B209, 3003 alloy, H-14 temper, 0.6 mm

(0.023 inch) minimum thickness with locking longitudinal joints. Jackets for elbows, tees and other fittings shall be factory-fabricated to match shape of fitting and of 0.6 mm (0.024) inch minimum thickness aluminum. Fittings shall be of same construction as straight run jackets but need not be of the same alloy. Factory-fabricated stainless steel bands shall be installed on all circumferential joints. Bands shall be 13 mm (0.5 inch) wide on 450 mm (18 inch) centers. System shall be weatherproof if utilized for outside service in utility tunnel / crawl spaces.

Item 9: Spec Section 23 07 11. After part 2.12 Flame and Smoke, add the following:

2.13 ADHESIVE, MASTIC, CEMENT

A. Mil. Spec. MIL-A-3316, Class 1: Jacket and lap adhesive and protective finish coating for insulation.

B. Mil. Spec. MIL-A-3316, Class 2: Adhesive for laps and for adhering insulation to metal surfaces.

C. Mil. Spec. MIL-A-24179, Type II Class 1: Adhesive for installing flexible unicellular insulation and for laps and general use.

D. Mil. Spec. MIL-C-19565, Type I: Protective finish for outdoor use.

E. Mil. Spec. MIL-C-19565, Type I or Type II: Vapor barrier compound for indoor use.

F. ASTM C449: Mineral fiber hydraulic-setting thermal insulating and finishing cement.

G. Other: Insulation manufacturers' published recommendations.

2.14 MECHANICAL FASTENERS

A. Pins, anchors: Welded pins, or metal or nylon anchors with galvanized steel-coated or fiber washer, or clips. Pin diameter shall be as recommended by the insulation manufacturer.

B. Staples: Outward clinching Monel or galvanized steel.

C. Wire: 1.3 mm thick (18 gage) soft annealed galvanized or 1.9 mm (14 gage) copper clad steel or nickel copper alloy.

D. Bands: 13 mm (0.5 inch) nominal width, brass, galvanized steel, aluminum, or stainless steel.

Item 10: Spec Section 23 07 11, part 3.2, Insulation Installation. After part

3.2.B, add the following:

C. Not Used.

D. Rigid Cellular Phenolic Foam:

1. Rigid closed cell phenolic insulation may be provided for piping for temperatures up to 121 degrees C (250 degrees F).

3. Provide secure attachment facilities such as welding pins.

4. Apply insulation with joints tightly drawn together

5. Apply adhesives, coverings, neatly finished at fittings, and valves.

6. Final installation shall be smooth, tight, neatly finished at all edges.

7. Minimum thickness in millimeters (inches) specified in the schedule at the end of this section.

ITEM 11: Spec Section 23 07 11, part 3.2, Insulation Installation, E. Cellular

Glass Insulation. After part 3.2.E.2, add the following:

3. Apply insulation with joints tightly abutted. Seal longitudinal self-sealing lap. Use field fabricated or factory-made fittings. Seal butt joints and fitting with jacketing as recommended by the insulation manufacturer. Use 100 mm (4 inch) wide strips to seal butt joints.

4. Only cellular glass insulation is permitted above slab in Chiller Building

188. See Drawing MP101.

F. Flexible Elastomeric Cellular Thermal Insulation:

1. Apply insulation and fabricate fittings in accordance with the manufacturer's installation instructions and finish with two coats of weather resistant finish as recommended by the insulation manufacturer.

2. Pipe and tubing insulation:

a. Use proper size material. Do not stretch or strain insulation.

b. To avoid undue compression of insulation, provide cork stoppers or wood inserts at supports as recommended by the insulation manufacturer.

Insulation shields are specified under Section 23 05 11, COMMON WORK

RESULTS FOR HVAC.

c. Where possible, slip insulation over the pipe or tubing prior to connection, and seal the butt joints with adhesive. Where the slip-on technique is not possible, slit the insulation and apply it to the pipe sealing the seam and joints with contact adhesive. Optional tape sealing, as recommended by the manufacturer, may be employed. Make changes from mineral fiber insulation in a straight run of pipe, not at a fitting. Seal joint with tape.

3. Apply sheet insulation to flat or large curved surfaces with 100 percent adhesive coverage. For fittings and large pipe, apply adhesive to seams only.

4. Pipe insulation: nominal thickness in millimeters (inches as specified in the schedule at the end of this section).

Item 12: Spec Section 23 07 11, part 3.3, Pipe Insulation Schedule. In the fifth row from bottom, first cell on left, delete the phrase “(CH and CHR within chiller room and pipe chase and underground).” Replace the deleted phrase with the following:

“(CH and CHR within chiller room and pipe chase and underground below the

Chiller Room Corridor)”

Item 13: Spec Section 23 07 11. After part 3.3 Pipe Insulation Schedule, add the following:

3.4 PRE-INSULATED PIPING SYSTEM

A. Installation:

1. Provide the service of a manufacturer’s representative to instruct the contractor on the installation procedures of the piping system and to be present on site to assist during critical stages of installation and testing. The representative must be qualified by the piping system manufacturer with responsibility to provide field technical assistance.

2. When the manufacturer’s representative is on-site, a report shall be produced consisting of the installation log indicating installed conditions, field observations, and pressure test results signed by the manufacturer’s representative, the contractor, and the VA-COR. Include documentation by the manufacturer’s representative that the installations conform with the manufacturer’s recommendations.

3. A minimum of six inches (6”) of sand or fine gravel bedding shall be placed all around the pipe in the trench. This bedding/fill shall be hand tamped and compacted around the pipes in six-inch (6”) lifts until the fill is six inches (6”) above the top of the jacketing material. The remaining height of the trench shall be evenly and continuously backfilled and compacted in uniform six-inch (6”) lifts with suitable, clean excavated soil.

4. Field joints shall be installed as described in Part 2 - Products.

3.5 TESTING THE COMPLETE PIPING SYSTEM

A. Testing Chilled Water Piping:

1. Upon completion of the pre-manufactured and field-insulated pipe installation, the piping system shall be hydrostatically tested to 1-1/2 times the operating pressure.

2. The hydrostatic test pressure shall be held for no less than one hour.

3. Before testing is initiated, perform safety precautions and coordination with Section 01 35 26 SAFETY REQUIREMENTS.

Item 14: Spec Section 26 05 19 part 2.4 Control Wiring. In paragraph 2.4.A, delete the phrase “equipment manufacturer” and replace with the word “Contractor.”

II. Drawing revisions are as follows:

1. MP 101:

A. Rewords Keynote 25.

B. Detail F5: Applies Keynote 25 to above-slab piping in Building 188 and its adjacent corridor.

2. MP103:

A. Add Keynote 30 under the Sheet Keynotes block in the sheet’s right-side margin.

B. Detail F5: Applies Keynote 30 where chilled water piping transitions from below grade to crawl space or utility tunnel.

C. Keynote 21: Delete “Conduit up to level above” and replace with: ¾” conduit and cabling up to level above. See detail D1 on Sheet MP501 for conduit and cabling requirements.”

D. Keynote 22: add the words “and cabling” after the word “conduit”.

E. Keynote 24: add the words “and cabling” after the word “conduit”.

F. Keynote 26: add the words “and cabling” after the word “conduit”.

3. MP401:

A. Detail B2:

1. Notes transition points for above- and below-grade, field-insulated pipe.

2. Clarifies the use of field-applied insulation with jackets in above-grade conditions.

3. Adds a note to refer to sheet AE402 for additional details.

B. Detail F1: Defines the transition point from pre-insulated to field-insulated pipe.

4. MP501:

A. Detail F8:

1. Updates the notes labelling insulated and pre-insulated piping.

2. Defines the transition point from pre-insulated to field-insulated pipe.

B. Detail D8:

1. Removes the reference to pre-insulated piping and replaces with insulated piping.

C. Detail D1: Adds BAS notes 1, 2, 3, and 4 under the controls table.

☐ Attachments: MP101, MP103, MP401, and MP501

Signed by: Date: March 28, 2025

Copies: ☐ ☐ ☐ ☐ ☐ ☐ ☐ File