The Bosarge Family Educational Center at the Coastal Maine Botanical Gardens

The Bosarge Family Education Center at the Coastal Maine Botanical Gardens was designed through a collaboration between our firm, and a local Maine architecture firm, Scott Simons Architects.

The client wanted to construct a new education center adjacent to their existing visitor’s center to serve as a model of sustainable, energy-efficient design. From the outset, the client outlined strict environmental guidelines with the goal of a LEED-Platinum, net-zero, beautiful building blending into the context of the surrounding gardens. The building was also to be an active teaching tool by outwardly demonstrating energy and resource conservation to visitors.  

This net-zero building is designed around a central open gallery: a gateway to the gardens. Two wings extend from this central core into the landscape, one housing administrative functions and the other flexible public space. Extensive glass enhances the connection to nature for occupants.

 The pre-determined site was a confined parcel adjacent to an existing visitor’s center. Located in a valley, this site presented a challenge to the design team of maximizing the solar access critical to net-zero performance.  In addition, the client wanted to preserve as many of the large coniferous trees as possible. The site, along visitor’s central circulation path, allows the staff to be connected to the arrivals and departures of guests.

The orientation of the building allows for the use of passive solar strategies, optimizes the orientation of the roof-mounted PV and solar hot-water panels, and minimizes the impact to the existing site and trees.   Meters provide real-time energy data for all systems. Signage and a “truth wall” educate visitors about the buildings sustainable features. The highly insulated building envelope, high levels of daylight, and automatic controls optimize occupant comfort.

The client set forth a strict schedule for the project in order to preserve the experience of visitors during the high summer season. To meet this tight schedule a panelized construction system was used which allowed for off-site fabrication, minimized on-site waste, site impact and time. This project is the first net-zero project by our office completed utilizing a panelized system, and through careful thought and construction, it meets the air infiltration standards required for net-zero buildings. The panelized process offers a level of control and precision in a factory environment.  The envelope design and building assembly now established within the prefabrication parameters can be adapted for other projects.

The building design brings to life the mantra, “If a plant designed a building…”

Quick Facts

General

Location
132 Botanical Gardens Dr.
Boothbay, ME04537
United States
Building Type Education Center and Botanical Gardens
Project Type
Basis of Performance Claim
Bedrooms
Conditioned Floor Area 8 200

Energy Summary

Energy Data Type
Renewable Energy System Type(s)
Ratings
Annual renewable energy generated

Envelope and Mechanicals

Subslab assembly

4” EPS rigid insulation

Foundation wall assembly

4” EPS rigid insulation

Above grade wall assembly

Dense pack cellulose in 11–7/8” I-stud cavity

Door Assembly

Exterior doors, Low-E2, tri-pane, argon filled, 0.42 U-value

Air Changes per hour, ACH50

Project Team:

Other Team Members:

Ratings:

Awards:

Completion

Completion Date:

Scope

Type of Construction
Number of buildings
Floor area of each building
Bedrooms
Stories
Conditioned Building Volume
Conditioned Floor Area 8 200

Location and Climate Details

Education Center and Botanical Gardens

Address
132 Botanical Gardens Dr.
Boothbay, ME04537
United States
Location Type Rural
Climate Region Zone 6
Köppen Climate Type Dfb
Lat. / Long. POINT (-69.6590196 43.8761026)
Elevation 60
Solar Insolation 4.52 kWh/m2/day
Annual CDD and Base Temp |
Annual HDD and Base Temp |

Site

Site Conditions:

Site Description:

Monthly Energy Data and Utilities

Energy Data Type:

Electric Utility: Central Maine Power

Gas Utility:

Renewables and Energy Balance

Renewable Energy Sources:

Renewable Energy System Description & Details:

Annual renewable energy generated
Annual Renewable Energy Generated Data Type
Power Rating 45Watts
Renewable Energy System Type(s)
Source of Annual Production Data

Walls and Roof

Subslab assembly

4” EPS rigid insulation

Subslab R-value 20.00
Slab edge assembly

4” EPS rigid insulation

Slab edge R-value 20.00
Foundation wall assembly

4” EPS rigid insulation

Foundation wall R-value 20.00
Above grade wall assembly

Dense pack cellulose in 11–7/8” I-stud cavity

Above grade wall R-value 40.00
Cathedral ceiling assembly
Cathedral ceiling R-value

Windows and Doors

Window Assembly:

a. Windows: Low-e, tri-pane, argon filled, FSC certified
i. 0.16 U-value, 0.24-0.16 SHGC, 0.57-0.629 VLT
b. Skylights (Type 1) 16 mm nanogel-filled polycarbonate inner layer
i. 0.154 U-value maximum
c. Skylights (Type 2) Triple-glazed, low-E2, argon filled, 0.27 U-value

Door Assembly:

Exterior doors, Low-E2, tri-pane, argon filled, 0.42 U-value

Average window U-factor 0.16
Door U-Factor 0.42
Door Area

Mechanical Systems

Space cooling - Manufacturer & Model Mitsubishi,
Space heating - Manufacturer & Model Mitsubishi,
Domestic hot water - Manufacturer & Model Solar domestic hot water
Domestic hot water - capacity
Ventilation - Manufacturer & Model ERV,
Lighting Manufacturer and Model
Lighting Efficiency
Mechanical Equipment Installation Details and Comments

Envelope

Air Changes per hour, ACH50
Air Changes per hour, CFM50

General Process

Design for Adaptability:

Software Tools

Software Tools:

General modeling information:

Lessons Learned

Outcome of Project Goals:

Discrepancies:

Rebates and Financial Incentives

Federal incentives
Local incentives
State incentives
Utility incentives
Other incentives
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