Hunnewell Elementary School SD HVAC System Selection
Transcript of Hunnewell Elementary School SD HVAC System Selection
Hunnewell Elementary SchoolSD HVAC System SelectionJune 25, 2020
Hunnewell Elementary School
Mechanical System Selection Overview
5 system options studied … 2 systems shortlisted
Energy Modeling and Life Cycle Cost Analysis
Pro/Con analysis
Base System VRF System + DOAS
Option 1 Displacement Ventilation + Radiant Floors + DOASwith Air-Cooled DX CHW/HW
Option 2 Displacement Ventilation + Radiant Floors + DOASwith Geothermal + CHW/HW
Option 3 Chilled Beams + DOASwith Geothermal + CHW/HW
Option 4 Displacement Ventilation + VRF + DOAS
Mechanical Systems
Mechanical Systems Base Option – VRF + DOAS
Mechanical Systems Option 4 – Displacement Ventilation + VRF + DOAS
Radiant Heat
Built-in shelving casework
Heavy duty cover
Radiant Ceiling panels
Mechanical Systems
Mechanical Systems
Hunnewell Elementary SchoolSD Construction Cost Estimate UpdateJune 25, 2020
HVAC system change of est. $2.8m has been factored in*
Refinements during SD
• Building area: Floor Plan development + $ 300k
• Site development + $ 1.5m
• Rubber flooring in lieu of Linoleum + $ 450k
• Foundation Waterproofing + $ 570k
• Schedule impacts due to COVID 19 + $ 500k
Total
$3,320,000
* Assumes VRF/Displacement Air type system
in lieu of Geothermal system
SD Construction Estimate is $2.4m above FS Estimate $45.06m:
• Straightening Café & Gymnasium Structure - $ 0
• Reduce Gross SF by +/-1,000 sf - $ 300k
• Remove 8 operable glazed walls and most sliding glazed doors - $ 500k
• Refine Sloped Roofs (use overhangs and clerestories) - $ 650k
• Reduce/simplify Site design scope - $ 500k
• Eliminate Foundation Waterproofing (awaiting final Geotech investigation results)- $ 550k
• Use Heat Mirror Glazing (at windows) in lieu of triple pane glazing - $ 200k
Total - $ 2,700,000
($300,000 below FS budget)
SD Construction Estimate is $2.4m above FS Estimate $45.06m:
Recommended VE items
Heat Mirror & Triple Glazing
Heat Mirror Film @ all Windows (0.22 assembly U-value – lower weight)
Triple Glazing Assembly: @ all Curtain Wall Units(0.22 assembly U-value)
Recommended VE reductions - $ 2,700,000
($300,000 below FS budget)
Recommended Value adds
• Laminated Glazing at Interior sidelights (in lieu of tempered) + $ 15k
• 4 Clerestory skylights + $ 50k
• Terrazzo flooring at Cafeteria space + $ 100k
• Outdoor Learning classroom @ low roof + $ 75k
• Hybrid Structure (wood roof structure at Café, Media Center, Lobby and Music) + $ 400k
• COVID 19 Schedule Impacts + $ 500k
Total + $ 1,140,000
Increase of + $ 940,000 to FS Construction Budget
Recommended SD Construction Budget: $ 46,000,000
SD Construction Estimate is $2.4m above FS Estimate $45.06m:
DD Value Engineering Goals:
• Water Softening System - $ 70k
• Reduce Roof Screening - $ 55k
• Eliminate Gymnasium divider curtain - $ 25k
Total
- $ 150k
Linoleum in lieu of Rubber flooring: - $ 450k
Not recommended by FMD
Hunnewell Elementary SchoolSD Construction Cost Estimate UpdateDiscussion
Hunnewell Elementary SchoolSD Project Cost & Schedule UpdateJune 25, 2020
Construction Manager Interviews
Anticipated proposals and interviews for the CM Selection Process:*
1. Shawmut Design & Construction
2. Gilbane Building Group
3. W.T. Rich Co.
4. Agostini Construction
* Consigli Co. has withdrawn from the process.
CM Procurement Schedule
• Finalize CM interview questions 6/25
• Construction Manager RFP proposals due 6/26
• CM Prequal Comm review meeting week of 7/6
• Construction Manager Interviews evenings of 7/15 & 7/16
• Construction Manager award 7/20 – 7/31
Schedule Milestone Update
• SD Value Engineering stage 4/24 – 6/18
• Set Schematic Design Construction Budget target 6/25 PBC Mtg – (Note: a few qualifiers to be confirmed after CM completes SD estimate)
• File Project of Significant Impact (PSI) with Town Permitting Authorities on 7/13
• Review FFE & Technology Budget and updated Total Project Budget at 7/23 PBC mtg.
• Start Design Development Phase 8/17
Hunnewell Elementary SchoolThank-YouJune 25, 2020