Through the generous grant support of the Community Preservation Committee, Housing Nantucket has been able to build Nantucket's (anticipated) first "LEED for Homes" certified house. The General Contractor on the job is Rob Andersen Construction and his team is using Insulated Concrete Forms (with a trade name of "Reddi-Form.") as well as a Sundura Solar Thermal Heating System. The LEED certification specialist is from Conservation Services Group. This page will highlight some of the progress we have made along the way!

In particular, the Clarendon House has a series of features which make it "green." Many of these features aren't innovative technologies - but rather smart thinking about the house. Site selection and development, a small building footprint, and orienting the house for maximum solar gain were basic design considerations to ensure the house would be appropriate for green construction. Next, the house was designed to efficiently use materials, to seal tightly against air penetrations (including the use of highly efficient spray foam insulation), to be durable and prevent moisture - all of which ensure the building is protected against decay and damage over time. Only after these basic considerations were made did we begin to introduce highly efficient technologies - such as low-e windows, "Water Sense" faucets and fixtures, environmentally preferable materials (such as sustainably harvest woods, recycled products, etc.), and low-VOC (volatile organic compounds) paints and adhesives. We also included a solar hot water system for our heating and a heat recovery ventilation (HRV) system to keep the good air in and the bad air out.

The Clarendon House produces domestic hot water and underfloor heat using solar collectors on the roofs. These collectors deliver heated water directly to a super-insulated tank. When there is demand for hot water it is drawn from the storage tank through a tankless/on-demand propane hot water heater. The tankless hot water heater will turn on and heat the water as needed to bring the temperature up to demand.

The Clarendon House uses a open cell spray foam for insulation in the areas built with stick framing, such as in the dormers and roof system. R values measure resistance to heat flow. The higher the R-value, the more insulating performance. This spray foam (Icynene®) expands to fill cracks while remaining flexible so that building envelope seal remains intact over time. The spray foam has an R-Value of 3.6 per inch. It acts as an insulation and air barrier to minimize air leakage and seal the building envelope. (See http://www.icynene.com/icynene-insulation/)

In the house, we are using a "Heat Recovery Ventilation" system. This system transfers heat from the outgoing, stale household air to preheat the incoming, fresh air. However, at all times, the air streams are kept separate to prevent air from becoming contaminated. The goal is to improve indoor air quality, control the moisture, and to filter contaminants.

Additionally, all of the appliances meet ENERGY STAR ratings (refrigerator, dishwasher, microwave, etc). Lights are either compact fluorescent light bulbs or LED lights.

As part of the LEED for Homes program, all units will be certified "ENERGY STAR." The Massachusetts New Homes with ENERGY STAR program is s a new construction program based on an energy efficiency standard developed by the Environmental Protection Agency (EPA). ENERGY STAR qualified homes are at least 15 percent more energy efficient than homes built to the 2004 International Residential Code (IRC). These homes are recognized for greater value, lower operating costs, and increased durability, comfort, and safety. ENERGY STAR certification requires pre-construction planning and post-construction inspections from an independent ENERGY STAR rater.

As stated previously, Housing Nantucket builds to the LEED®  for Homes  standards. The LEED® (Leadership in Energy and Environmental Design) Green Building Rating System is a voluntary, consensus-based national standard for developing high-performance, sustainable buildings. Members of the U.S. Green Building Council representing all segments of the building industry developed LEED®  and continue to contribute to its evolution. The U.S. Green Building Council is the nation’s foremost coalition of leaders from across the building industry working to promote buildings that are environmentally responsible, profitable, and healthy places to live and work.

Homes earn LEED®  for Homes at one of four levels– Certified, Silver, Gold, or Platinum. Homes are rated by a LEED®  for Homes provider who also advises throughout the planning and construction process. Housing Nantucket uses Conservation Services Group as its LEED®  for Homes provider.

LEED®  for Homes rates homes in eight categories:

1. Innovation & Design Process
2. Location & Linkages
3. Sustainable Sites
4. Water Efficiency
5. Energy & Atmosphere
6. Materials & Resources
7. Indoor Environmental Quality
8. Awareness & Education

Housing Nantucket is projected to be certified as LEED for Homes SIlver. :

(Highlights of credits pursued for Clarendon House, not a list of all possible credits.)

Innovation & Design Process (ID):

• 1.0 Integrated Project Planning - Early in the planning process HN met with the LEED provider to determine what credits would be pursued and what level of certification was the goal.
• 2.0 Durability Management Process - This process requires completing a durability risk evaluation, taking steps to install durability measures and then having a third party verify that these measures have been installed. Durability measures were installed which prevent damage from:
  • Exterior water
  • Interior moisture
  • Air infiltration
  • Interstitial (within the exterior wall) condensation
  • Pests
  • Heat loss
  • UV radiation
  • Natural disasters (none typical to this area of the country)
    
• 3.0 Innovative or Regional Design - Housing Nantucket is pursuing a possible Innovative Design credits
  1. A Home Monitoring System

Locations & Linkages (LL):

• 3.0 Preferred Locations - 75% or more of the perimeter borders previously developed land and the site is previously developed.
• 6.0 Access to Open Space - The site is within walking distance of permanently conserved open space.

Sustainable Sites (SS):

• 1.0 Site Stewardship - During construction disturbance of the site has been minimized and erosion controls have been put in place.
• 2.0 Landscaping - Drought tolerant, non-invasive plants are being planted. We have also demonstrated that no irrigation is necessary.
• 3.0 Heat Island Effects - Housing Nantucket ensured light-colored materials were used for paving areas.
• 4.0 Surface Water Management - HN's landscape architect (Bartsch & Radnor) designed the site for a minimum of impermeable surfaces. The runoff from roofs will drain into the sandy soils.
• 5.0 Nontoxic Pest Control - Wood to concrete connections are separated; all cracks, joints and penetrations are caulked or otherwise sealed; foundation walls are solid concrete; landscaping plans keep mature plants at least 24" from walls.

Water Efficiency (WE):

• 1.0 Rainwater Harvesting System - Housing Nantucket is using two rainbarrels to capture 50% of the runoff into a harvesting system for tenants to use on their gardens.
• 2.0 Reduce Irrigation Demand - We reduced irrigation demand by 98% for the maximum points.
• 3.0 Indoor Water Use - Homes have very high efficiency showerheads, "Water Sense" faucets and low-flow toilets.
  

Energy & Atmosphere (EA):

• 7.0 Water Heating - No piping is located in unheated spaces. Pipes within the walls are surrounded by cellulose insulation.

Materials & Resources (MR):

• 1.0 Material-Efficient Framing - By using Insulated Concrete Forms, HN has minimized framing waste. Construction plans included detailed framing drawings and cut lists.
• 2.0 Environmentally Preferable Products - Notice is given to all suppliers that HN will not use tropical wood and that wood must be FSC certified. Suppliers are instructed to notify HN if any wood being supplied fails to meet these requirements. A list is supplied by RDI to the vendors specifying which countries are considered tropical. Furthermore, we are earning points for using other Environmentally Preferable Products (EPPs) - low VOC paints; bamboo floors; Marmoleum resilient flooring; and low-VOC cabinets.
• 3.0 Waste Management - Nantucket's unique condition demands that construction waste be recycled before being hauled off island. However, there has been such a minimum amount of waste, the need for waste hauling has bee limited. Records are kept tracking how much waste is hauled to the landfill. Thus far, construction has been generating no more than 0.75 pound of waste per square foot of conditioned floor area.

Indoor Environmental Quality (EQ):

• 2.0 Combustion Venting - There are no unvented combustion appliances. Space and water heating equipment is sealed combustion. Carbon monoxide monitors are installed on both floors. There are no fireplaces in the homes.
• 4.0 Basic Outdoor Air Ventilation - The main bath in each house has a very quiet fan on a timer. The airflow can be increased when showering. The second bath also has a fan with a timed switch. A third party tests the performance of these fans.
• 6.0 Distribution of Space Heating & Cooling - Room by Room load calculations for the homes were performed.
• 8.0 Contaminant Control - A preoccupancy flush is performed in all homes before the occupants move in. This involves opening windows and circulating fresh air for a total of 48 hours once construction has finished.
• 10.0 Garage Pollutant Protection - LEED awards points to the village homes for having no garages.

Awareness & Education (AE):

• 1.0 Education of the Homeowner - Housing Nantucket staff will provide the tenant with an extensive operations and training manual. The manual contains information on maintaining all the systems in the house, as well as manuals for all the different appliances and fixtures installed. The manual also explains how all the different aspects of the home are designed to work together and discusses how to live in a very energy efficient, super insulated, tight home. Separate Solar Hot Water system manuals are also provided. We will provide a one-hour walk-through at closing.
  
  Public awareness has been cultivated through newspaper and magazine articles, running a Green Building Open House, and this website.

You can also visit Andersen Construction's photo blog at http://hntomnevers.blogspot.com/

Some photos:

ICF Blocks	Looking down the blocks	ICF Blocks
Blocks going up	Stacked Blocks	Concrete filled blocks
West Side of Unit, Showing ICF blocks and dormers	The dormers going up	Interior framing for second floor
	The view from the second floor across Tom Nevers West.
Exterior Sheathing and Windows going up	Interior spray foam - by R.A. Energy Inc.	Exterior shingles on, ready for landscaping and solar
Solar Panel System (L to R: Solar Panel feed tubes and monitor, pumps, tankless hot water systems, solar hot water tank)	Blower Window Test (This house is 6 times more tight than a typical home.)	Solar Panels installed
The FInal Product		RIbbon Cutting with State Representative Tim Madden, representatives from the Town of Nantucket, Representatives from the Community Preservation Committee, and invited guests.