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2017 Challenge Participant:

Lehto Design Build

Applicant: Nick Lehto

Project Address: Day Island Road, Dayville, CT 06241

Bdrms./Sq. Footage: TBD

Builder Website: www.http://www.lehtodesignbuild.com/

Project Overview Project Specifications Project Team Project Photos
The Lehto Design Build project in Dayville, CT.

General Project Overview:

We bought a summer cottage on Lake Alexander 8 years ago, which was built as a summer getaway with materials that were not meant to be highly efficient as it was only used for 3 months of the year. When our youngest child went off to college, we sold our home and focused our energy on making the "cottage" into our permanent future retirement home. After meeting with several builders and really discussing our options, we chose to build with Nick Lehto because his proposal sold us on so much more than just a house. He made us really take into consideration the future costs and viability of the structure we were about to create and use, hopefully well into our retirement years. Building green is not only respecting our environment by using sustainable and recyclable materials, its being responsible home consumers of energy as well. As we age into this home, the cost saving benefits from the decision to build a Net Zero home will be realized and this wonderful home will be passed onto our children.

Special Features:

  • Craftsman / Bungalow inspired design

  • Super Insulated building envelope

  • Lifetime Aluminum standing seam metal roof

Orientation and Envelope:

  • Orientation: While its ideal to orient a house towards the south to take advantage of passive solar heat gains and natural light, the small lot size and shading from trees on adjacent lots limited its potential. Still, besides the westerly lake views, a majority of the windows are located along the south side of the house to take advantage of these things.

  • Walls: Double stud walls from 10” deep. The cavity is filled with dense pack cellulose to achieve a R-Value of 45.

  • Roof: R-70 Loose fill cellulose

  • Foundation: 3” of closed cell spray foam R-21

  • Sub Slab: 2” XPS insulation R-10

  • Windows: This home features high performance triple pane window that offer R Values between R-5 and R-6.

  • Airtightness: To achieve desired efficiency goals, it is essential to have an air tight building envelople. This home achieved a blower door reading of below .6ACH50, which is 5x’s tighter than a code built home.

Heating, Cooling, and Hot Water:

  • Air-Source Heat Pump: A high efficiency Mitsubishi air- source heat pump was used to provide both heating and cooling, with efficiencies of 10.7 HSPF / 17.5 SEER

  • Domestic Hot Water: Water heating is provided via a 50 gallon heat pump water heater with a 3.42 energy factor (EF).


  • Ventilation: This home uses a high efficiency Energy Recovery Ventilator that removes stale air from the home, and supplies fresh filtered air.


  • Electrical: All lights are LED. Appliances are Energy Star certified. 


  • Renewables: A 12.06KW Photovoltaic System was installed to reduce the remaining energy demands of the house. This system is slightly larger than what would typically be used on a house this size, but it was increased to compensate for non-optimal orientation and also shading from trees on adjacent lots.
Website by: 505 Creative Services, Guilford CT  |  www.505Creative.com
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