COST DRIVERS IN PHIUS AND
ZERH HOME CONSTRUCTION
Patty Shields, LEED APMetro Green, LLC
Falls ChurchResidential Builders
Donaldson Run Passive House
PHIUS Certified 2015
Other certs – LEED, ZERH, Energy Star, Earthcraft, Green Home Choice
Keys to success• A good plan and a team that gets you there
• Motivated client with realistic expectations• Experience/motivated builder• 3rd Party Rater • Energy Star Certified HVAC Installer
• PHIUS, ZERH, Energy Star and IAQ Plus
Cost drivers
• Material Costs• Labor
• Quality Control
Cost Implications by PHASE
Design and Spec development:
• Passive Solar Design inputs• Energy Modeling • Wall assembly, fenestration,
Mechanical plan• Assembling your team – Experience,
curiosity, motivated
Help your builder with good details
FoundationInsulation, Eliminate Thermal Bridges, Vapor barrier
FramingReducing Thermal Bridges and High R• double wall, outsulation, SIPs
VAPOR
RETARDER
Windows:PH certified triple glaze windowsCost and Installation v double glaze
Exterior WRB and AirsealingOutsulation v Zip-R v peel and stick continuous
Testing:Smoke tests, real tests, and what they reveal: KEEP IT SIMPLE
Insulation Approaches:• Flash foaming – Closed Cell• Open Cell at bands• Dense pack cellulose, rockwool• Quality CONTROL
Mechanicals:
• Heat Pumps with VRF – Variable Refrigerant Flow • Mini-Splits• Whole home
• Ventilation Strategies – ERV • Dehumidification
Mechanical Install:• Who is your installer?• Energy Star certified? Motivated?• Sealing the ducts – QUALITY
CONTROL• Mastic, Flash foaming for
condensation• Testing – Duct Blaster
Final Testing and Commissioning:
• Duct Blaster• Blower Door• Balancing• Documenting Lessons Learned
Lessons Learned:
• Understand your client’s real goals:• Reduced carbon footprint
• Embodied energy- tear down
• IAQ• Energy independence
• Solar needs to be in the mix
• Thought leader – exemplar
What Cost Balancing do we grapple with most:
• Solar PV v PH certified windows• Venting dehumidification v ERV + dehu• Outsulation v ZipR v closed cell flash