Building an Affordable Net Zero Home...Cheap out on the stuff that is easier to replace or add...
Transcript of Building an Affordable Net Zero Home...Cheap out on the stuff that is easier to replace or add...
Part 1: A Case Study Part 2: Our Guide
Building an Affordable Net Zero Home
• Greenfield, MA • .3 acres
The Giordano – Smeltz Residence Case Study
503 kW Surplus energy generated
5144 kW Total energy generated
68o F Avg. winter-time 1st floor temp.
8203 HDD Base 68o F
Performance Oct. 2013 – Oct. 2014
Envelope
Infiltration • .54 ACH50
R Values • Walls 46 • Roof 78-96 • Foundation Wall 30 • Foundation Slab 20
Windows
• Mostly double paned • Weighted avg. U value .28
Dimensions First Floor
Systems
Photo Beth Reynolds
Heat and Ventilation
Systems
• 4.5 kW micro-inverter PV system • Drain-back solar hot water system, 80 Gallons of
storage, 4 x 10 panels
Final Cost
$145,000 + $60,000 = $205,000 • Includes $15,000 in incentives • Does not include a cost for Spartan’s labor
Construction Land Combined
www.ZeroandBeyond.com/cost
Our Guide to Affordability Big Picture Choices
• Pick an accessible site with city services • Stick with simple shapes • Single floor • Build as small as you can • Stay within code; avoid engineering
• No basement • Passive Solar – Consider those windows as
cheap solar panels • Placement of windows and doors • Frost Protected Shallow Foundation (FPSF)
Big Picture Choices
System Choices: Heat
• Avoid central heating systems and burning things
• Use air source heat pumps (AKA mini-splits, ASHP)
• Open floor plan • What about wood?
• Direct Ventilation
• Heat Recovery Ventilator (HRV)
System Choices: Ventilation
• Solar Hot Water (SHW)
• Air source hot water heat pump (ASHWHP)
• Water heat recovery
System Choices: Hot Water
goSpartanSolar.com
Cheap out on the stuff that is easier to replace or add later.
• Appliances • Trim • Cabinets
Material Choices
• Sinks • Toilets • Interior doors
• Solar PV and Hot Water • Do put in the pipes/conduit and get the right tank
Material Choices: Salvage
• Windows and doors • Foam board • Sinks, cabinets, lighting and plumbing fixtures • Avoid salvage toilets
Easily Salvaged Materials
• Trim, Interior and exterior • Siding • Roofing
Material Choices
• National database of incentives: dsireusa.org
Massachusetts • Home Energy Star certification – up to $7000 • Solar hot water – up to $4500 plus tax credits • Air source heat pumps – up to $1250 / unit • Solar Photovoltaics (PV) – Low interest loan
program plus tax credits. Safe to budget earning $1000/year for 7 years from SREC’s.
Capitalize on Incentives
Do it Yourself (DIY)
Resources • GCC – Greenfield Community College • SEON – Sustainable Outreach Network • NESEA – Northeast Sustainable Energy Assoc. • WMGC – Western Mass Green Consortium • GBA – Green Building Advisor • JLC – Journal of Light Construction Field Guides • For Pros By Pros books • ZeroandBeyond.com