Friday, July 16, 2010
Carlisle School project reviewed, utility bid accepted
The Carlisle School Building Committee (SBC) reviewed the latest design iteration of the new school building at their July 8 meeting, before discussing the three bids received for the pre-construction utility work. They ultimately decided to recommend that the Selectmen accept the $343,495 bid of D’Amico, Inc., the construction company used for the school’s Wastewater Treatment Facility. The Selectmen approved the D’Amico bid at their meeting on Tuesday, July 13 (see article, page 7).
The school renovation project is being designed by HMFH Architects, Inc. of Cambridge. Changes to the design of the new building include a more traditionally peaked roof, eliminating the previous open roof concept which Supervisor of Building and Grounds David Flannery had flagged as a maintenance concern. An accessible, open flat area on the rear of the roof will accommodate the heating, ventilation and cooling (HVAC) system, explained HMFH Architect Laura Wernick. The flat area will have a pitch that will drain water away from the HVAC systems. Workers will reach the system via a slanted “ship’s ladder,” added HMFH Architect Andrea Yoder.
Form over color
The architects presented a colored sketch of the proposed design, which caused Warnick to field many questions about the final color scheme of the building. Carlisle’s Owner Project The architects presented a colored sketch of the proposed design, which caused Wernick to field many questions about the final color scheme of the building. Carlisle’s Owner Project Manager Sean Fennell of Daedalus, Inc. suggested that it was too early to talk about colors and Wernick shifted the discussion to the form or shell of the building. She noted that skylights will bring in natural light.
Committee member Janne Corneil questioned the bulk of the side brick wall and said that the new design looked “too much like a residential building.” Wernick replied that she envisions different shades of brick or stone on the side of the building to reduce the appearance of bulk. Corneil and Wernick decided to meet during the week of July 19 to discuss the design.
Large swing in utility bids
Three bids were received for the early utility work to reroute the utilities from under the school plaza to behind the Wilkins and Corey Buildings. Tasco Construction Inc. of Belmont had the lowest bid, at $182,000, more than $150,000 less than the next highest bid of $343,495 by J. D’Amico, Inc. of Randolph. The third company, Bridges, LLC of Milford, came in highest at $458,950.
However, the low bid was considered unrealistic. Fennell had updated his initial project estimate from $150,000 to around $360,000 due to the addition of transformers and other work which he detailed in a bid addendum included in the bid package. Tasco said they had not received the addendum, Fennell reported.
If Tasco does not withdraw their bid, Wernick advised that the committee would have to disqualify them on the basis of not acknowledging the addendum, before the committee could award D’Amico the contract. The committee voted to recommend to the Selectmen that, in the absence of a receipt of a letter from Tasco withdrawing the bid, they disqualify Tasco and award the contract to D’Amico. D’Amico can start as early as July 19.
Tracking changes to the budget
Fennell explained that the extra cost for the utility work will come out of the design contingency fund, prompting Town Treasurer Larry Barton to inform the SBC that Selectman Doug Stevenson has asked,“How can we see the progression of changes on paper?” Barton said that Stevenson was not being critical of the process but instead wants to understand how changes are tracked. In a letter to the SBC, Fennell explained that the design contingency fund contains $1,167,491. Fennell proposed “to take 16% of this to pay for the $191,543 overage in the early site utility package, leaving $975,948 in design contingency remaining.”
Committee member Robert Wiggins pointed out that the work is not strictly design work, but agreed with Barton who said that “it doesn’t really matter” where the money is moved from, as long as it is tracked. Fennell said he would go through any future estimate changes with Barton and Barton agreed to Fennell’s suggestion.
School input sought for planned engineering lab
SBC member Bill Fink pointed out that teachers need to do a final review of the floor plans and Wernick said the review must be completed within three weeks so that the architects can finish the design by the end of September. Fennell agreed, saying, “We must have solid plans when we submit them to the MSBA.”
Wernick said the architects need a better understanding of the program of use planned for the technology and engineering lab. She said that former superintendent Marie Doyle “had a vision” for the space, “but not a program. It’s been a blank space for us. We need a program for this space.” Fink said the space would be used primarily by middle school students, but member Don Rober said younger students may also access the room.
Wernick proposed meeting with new superintendent Joyce Mehaffey and a group of teachers in the next few weeks. “Meanwhile,” she said, “we will lay out the floorplan to the best of our abilities.” She will work with a consultant who is experienced in technology and engineering labs. “We must get these drawings done so we can get cost-estimate bids.” Reached later by email, Mehaffey said that a meeting with teachers will be organized over the summer.
New HVAC system
Committee members held a lengthy discussion on the displacement ventilation system being planned for the new building. The other school buildings are heated through a “mixed air distribution” system, meaning that air is brought into classrooms via fans and is mixed evenly with the air already in the room. Fan outtakes remove the air as new air is introduced. Any contaminants (pollen, dust) that are in the air are also distributed evenly. All the buildings are heated by natural gas, explained Supervisor of Building and Grounds David Flannery by email.
Fresh air at 65°, two zones
The new system is designed to introduce fresh air at the floor level at a low velocity. The air, which is kept at a constant 65° – 68°F sinks down and moves slowly across the room until it meets with a heat source such as students. The cool air warms, rises slowly next to students, and is finally vented out at the top, taking contaminants away with it. Buildings with this system usually have rooms that have high ceilings, but the optimal “air comfort zone” is the first six feet, vertically, in the room. The system is quiet due to the low velocity air flow. The air coming into the system from outside will be warmed when it is below 65°. (For more information on displacement ventilation systems, see: www.price-hvac.com.)
Fennell said that the two zones in the new building will be configured vertically, with the right side of the building closest to the parking lot on one zone and the left side on a second zone. According to Flannery, the zones are split vertically because “this is how the building areas will be used on the off-school hours, particularly in the summer months.” The zone on the left will include the administrative offices and the preschool on the first floor, and four first-grade classrooms on the second floor. In the right zone will be the four kindergarten classrooms on the first floor and the four second-grade classrooms on the second floor.
Heat a concern
Carlisle’s Owner Project Manager Sean Fennell of Daedalus, Inc. said the rooms will be comfortable on warm days, but could be hotter in a heat wave. “But the dew point would be low,” he added. Fennell said the roof will be constructed to support a condenser if “in the future you want to add air conditioning.”
Campus has scattered a/c
There are scattered places on the school campus that have air conditioning, explained Flannery: “[The] Grant [building]does not have a/c, except for the Special Education Office on the second floor which has two window units. In Robbins the three second-grade classrooms as well as the library, nurse and student services office have a/c via two roof-top units. The administration offices in Wilkins have a/c via window units (four units) as well as the business office in Spalding (two units). The Corey music room and auditorium have a/c via roof top units.” ∆
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