Net-Zero Energy House

"Net-zero"
means that the home should produce as much energy as it consumes measured on an annual basis.

Built:	Circa 1880s
Retrofitted:	2011
2011 owner:	PUSH - People United for Sustainable Housing
2011 Architect:	Eco_Logic Studio
2011 Retrofitting construction company:	Lamparelli Construction Company
2011 Retrofitting income source:	2005 Green Development HUD grant
PUSH Green Development Zone Award:	First place out of 11 finalists from countries around the globe: 2011 Changemaker's International Sustainable Urban Housing Competition... Sponsored by U.S. Department of Housing and Urban Development (HUD), the U.S. Department of State and the American Planning Association... See Finalists and Buffalo Rising article
2010 award:	2010 WNYSEA "Leadership in Sustainable Design" Award.
ADDITIONAL INFORMATION

TEXT Beneath Illustrations

Note solar thermal unit on the roof (detail in next illustration below).

One of 50 PUSH owned properties in a 25 block radius PUSH Green Development Zone centering on Massachusetts Avenue.

About half of the properties are existing houses that are in need of rehabilitation; the other half are vacant lots. Building new housing is not part of the project. The main source of funding is a 2005 Green Development HUD grant.

Energy Star-rated “cool” metal roof ... Solar thermal. See text below.

Cement composite siding. Superinsulated. See text below.

Local 17 dug a 100’ L x 6’ W x 6’ D trench in the vacant lot next door. At six feet deep we are below the frost line where the ground temperature is a constant 50-55 degrees.

We buried 700’ of plastic piping at the bottom of the trench with two supply and return lines connected to a series of pumps, controls, and mechanical equipment in the basement.

The key piece of mechanical equipment is the heat pump - a water to water heat exchanger that utilizes energy efficient compressor technology to extract heat from an anti-freeze solution that cycles through the ground loops and then super heats water that gets distributed through a network of underfloor radiant tubing that runs beneath each floor of the house.

Back of house with Solar PV on the roof. See text below.

Solar PV. See text below.

Basic information:

3 bedroom
1300 square feet
Built circa 1880s
PUSH will own the house to retain community control and to ensure it remains affordable for low income residents in the community
Hoping to occupy by November 1, 2012

This is a demonstration project, not a model home. Under current market conditions and government subsidy programs, it is not possible to replicate and scale-up the net zero design concept within the PUSH Green Development Zone.

With this project PUSH attempted to demonstrate two things:

1. Cutting edge renewable energy and energy efficiency technologies and installation techniques, including solar thermal (or solar hot water), solar photovoltaic, geothermal heating, and super insulation.

2. The potential of affordable housing development projects to drive community-controlled economic development and job creation.

Features of the project:

“Net-zero” means that the home should produce as much energy as it consumes measured on an annual basis
Environmental hazard abatement - all asbestos and lead-based paint was removed from property at the beginning of the project

Solar thermal - Roof-mounted system harnesses sun’s energy to pre-heat all of the domestic hot water (bathing and drinking water) in the home. On a sunny day the system will heat water to at least 120 deg. On colder, cloudy days the system is boosted by a tankless, on-demand hot water unit.

Solar PV - Roof-mounted 4.65 kilowatt system will meet the electrical load for all appliances, lighting, outlets, and mechanical systems in the home. It is a grid-tied system. Any additional energy that is produced gets sent back to the electrical grid and PUSH receives a credit from the utility at pre-set rate.

Geothermal - horizontal ground loop system designed and installed with 100% volunteer/in-kind labor by Local 22 Plumbers and Steamfitters union apprentices, Local 17 Operating Engineers union apprentices, Watts Architecture and Engineering, and green job trainees.

Local 17 dug a 100’ L x 6’ W x 6’ D trench in the vacant lot next door. At six feet deep we are below the frost line where the ground temperature is a constant 50-55 degrees.

We buried 700’ of plastic piping at the bottom of the trench with two supply and return lines connected to a series of pumps, controls, and mechanical equipment in the basement.

The key piece of mechanical equipment is the heat pump - a water to water heat exchanger that utilizes energy efficient compressor technology to extract heat from an anti-freeze solution that cycles through the ground loops and then super heat water that gets distributed through a network of underfloor radiant tubing that runs beneath each floor of the house.

Superinsulated building envelope - We did extensive air sealing using caulk and spray foam before insulating. Exterior walls have been insulated to an R-30 rating and the attic floor has been insulated to an R-50 rating. We dense packed the wall cavities with 4” of cellulose insulation and then faced the studs with 3” of polyiso foam board. The attic floor was flash sprayed with foam (1”) and then topped off with 18” of cellulose.

Whole house ventilation system - We installed an Energy Recovery Ventilator, an air-to-air heat exchanger that provides whole house ventilation. The unit exhausts stale indoor air and takes in fresh outdoor air. The air streams cross paths allowing for the exhaust air to condition the intake air to room temperature conditions.

Energy Star-rated “cool” metal roof - Helps to passively cool the home.
PUSH worked with two partner organizations to offer hands-on green job training opportunities to West Side young adults and adults with barriers to employment.

For 10 months the net-zero house hosted two crews of 10 YouthBuild program trainees. The YouthBuild members worked alongside tradespeople and union apprentices to complete the rough framing, plumbing, and electrical work in the house.

A couple YouthBuild members transitioned into full-time work on PUSH’s 11-unit green affordable housing development project on Massachusetts Ave. where they receive living wages as full-time employees of Lamparelli Construction Company. Another member is now a 2nd year plumbing apprentice with Local 22 Plumbers and Steamfitters.

30+ trainees from the Outsource Center, a grassroots work readiness and construction training organization based on the East Side, joined the project over the course of the final 10 months and completed much of the insulation and finish work in the house. They were led on the job by a veteran union carpenter. Most of the Outsource trainees have since gone on to work at the renovation of the Lafayette Hotel.

Text supplied by PUSH