Meditch Murphey Architects A1 Sofeh Co. Isfahan, IRAN, Tel: (311)663 9087, Fax:(311)663 9088, Designing the Zero Energy House NetZEB Concepts

Meditch Murphey Architects A1 Sofeh Co. Isfahan, IRAN, Tel: (311)663 9087, Fax:(311)663 9088, www.a1sofeh.com

Designing the Zero Energy House

NetZEB Concepts

A1 Sofeh Work Shop for SABA Seminar 21/02/1392


Who We Are

► Eyvan Sofeh Co.

Internationl Design, Construction & Development

► We Do:

► Engineering

► Procurement

► Construction

► Management

► Financing


What IS NetZEB?

► Goal : House is designed to produce as much energy (Renewable) as it consumes on yearly basis.

► The power grid is our storage system. The surplus of energy produced in low peak time is to be transferred to the Grid

► Reduction on Energy Consumption is the first priority. This purpose can be achieved through Passive Energy Home Design


Our Motivation

► To prove that a NetZEB, market-viable speculative house is possible.• Cost competitive• Beautiful• Sustainable

► Because energy independence and health Natural Environment is important.

► Because Energy Resources are limited and should be saved as well for next generations

► Because reduces Energy bills amount for home owners


► Highly Insulated, Tightly Sealed Envelope

► High Efficiency Mechanical System

► High-Efficiency Appliances

► Taking Advantage of Free renewable Energies for Heat, Cool, and Electricity

How to achieveNetZEB


Beyond NetZEB

► Water efficiency

► Sustainable materials

► LEED-H Platinum Rating• Leadership in Energy &

Environmental Design for Homes.

• Levels (high to low) Platinum Gold Silver Certified

• EnergyStar Home

► Public Outreach and Education

► Market Viability


Design Process

► Integrated Design Team• Architect• Owner• Builder• Mechanical Electrical and

Plumbing Engineer (MEP)• Structural Engineer• Civil Engineer• Landscape Architect• LEED Consultant/Green-

Rater

► Sustainability from Day-1

► Staying focused on goals

► Accepting trade-offs• Energy vs. water vs.

materials• Sustainability vs. cost• Up-front vs. recurring costs

► Exploit synergy, know when to stop


The Architectural Design

(Example)

► Comfort

► Aesthetics

► Efficiency

► Sustainability

► Cost

► Context

Kitchen viewed from Dining RoomFront of house with entry and pergola.First floor

Second floorLiving room & Dining room viewed from Kitchen

Solar array


Site Selection(Example)

► Infill vs. Virgin Territory

► Public Amenities• Transportation

29

T2

3232

1/4 mi1/4 mi 1/2 mi1/2 mi


Site Selection (Example)


► Public Amenities• Transportation• Community Services• Greenspace

PARK

CLUBHOUSE


Site Selection (Example)


► Public Amenities• Transportation• Greenspace• Community Services

► House Orientation for optimum solar income:• Passive solar design• Solar hot-water and

Electricity.


Envelope – Insulation

► The cheapest energy to buy is the energy you don’t use.

► Continuous Air-Barrier, sealed at all openings and edges.

► Basement walls : R-20 (R-13 by code)

► Slab : R-10

► Wall : R-33 (R-19 by code)

► Roof : R-50 (R-30 by code)

► High-reflectivity roofing to reduce heat island


Envelope – Windows

► Windows/Doors • U-factor = 0.32 (R3)• Solar Heat Gain Coeff.

(SHGC) = 0.28



► Windows/Doors • U-factor = 0.32 (R3)• Solar Heat Gain Coeff.

(SHGC) = 0.28

► Limit East and West facing Glass• At least 50% more glass

on North and South than on East and West.

► Shade South-facing Windows and Doors• exclude heat in summer,

admit it in winter

SOUTH



EAST

WEST

NORTH

SOUTH

Limit East and West facing GlassAt least 50% more glass on North and South than on East and West.


Passive Mechanical Systems –

Nature’s Services

► Natural ventilation during swing months• Operable windows• Cross-ventilation• Timed or Humidistat

controlled fans in bathrooms.

► Awnings and trees reduce cooling requirements in summer.

► South orientation allows for some passive heating in winter.


Active Mechanical Systems –

Heating & Cooling

► Geothermal – Ground Source Heat Pump

► Energy Recover Ventilator

► Sealed duct work, all INSIDE the Envelope.

► Mechanical Ventilation – “seal tight, ventilate right” – 0.35 air changes per hour.

► House zoned to allow upstairs and basement to be ‘shut down’ when not in use. Master bedroom is also a separate zone for day-night differential control.

BASEMENT

ZONE 1

ZONE 2

ZONE 3

ZONE 4


Appliances

► EnergyStar Appliances• Refrigerator• Convection ovens• Induction cooktop• Dishwasher• Clothes Washer (no

dryer is energy efficient – consider clothesline instead)

► Compact Fluorescent (CFL) and LED Lights, EnergyStar Ceiling Fans.

► Gas fireplace w/ Electronic Ignition


Power Generation(Example)

► 9.5 kW Photovoltaic array • Goal: 100% of annual

electricity needs • 49 panels on the roof• Two inverters in the

basement• Grid tied : power grid is our

storage system

► Solar Hot Water system• Goal: 85% of hot water

needs• 2 flat panel panels on roof

(tubes another option)• 120 gallon pre-heat tank in

basement


Energy Balance

► Achieving Zero Energy is the goal, but don’t have to go that far to save money and the environment.

► High efficiency envelope, HVAC and appliances cuts demand to manageable level.

► Cut usage first before buying more PV panels.

► Knowing when to stop – the better it is, the harder it is to improve.


Water Efficiency

► No irrigation system required. Plants are drought tolerant.

► Low-flow fixtures• 1.75 gpm shower head• 1.5 gpm lavatory faucets• 1.1 gallon per flush

toilets• Clothes Washer – Water

Factor ≤ 5.5

► Recirculation pump – water recirculated to tank until desired temperature is reached.

► Fixture-by-fixture graywater reuse – had to delete because of county permit trouble.

► Still considering rainwater harvesting

s s sMotion Sensor

Hot

Motion Sensor Motion Sensor

UMP

sink

sink

tub

shower


Finish Materials – Sustainability

► LEED Recognizes following materials as ‘environmentally preferred’:• FSC Certified (Forrest

Stewardship Council)• Recycled (including

rubber)• Reclaimed• Local• Rapidly Renewable

(bamboo, linoleum)

► Low VOC (Volatile Organic Compounds).

► No urea-formaldehyde

► No exotic woods

► Durability – more about how and where materials are installed than materials themselves.


Finish Materials on the Example Project

► No added urea-formaldehyde in anything

► Low VOC paints, sealants, adhesives.

► Hard-floors instead of Carpet• FSC / reclaimed / local

Hardwoods• Engineered wood• Linoleum• Rubber

► Cabinets• FSC / reclaimed / local

woods

► Framing FSC framing or trim • Window / Door framing –

hard to get.


Landscaping (Example)

► Keeping rainwater on-site• Nearly 100% Pervious

surfaces.• Light colored surfaces

to reduce heat island effect

• Rainwater harvesting • Green Roof (OPTION)


Landscaping(Example)

► Shading the House (but not the panels)

► Saving potable water• 100% Drought tolerant• High-efficiency

irrigation system

► Native Species Only

► Protecting house• No materials that

attract termites within 2 ft. of house.

► Minimize site disturbance, add plantings to eliminate erosion.


Cost Advantages of Green Building

(Example)

► Basically prepaying your energy bills for next 25 years.• It’s (relatively) inflation-

proof• It’s deductible

► Comfort• Sustainable materials

are healthier for you and your family to live with.

• Tight, energy-efficient construction is more comfortable to live in (when properly designed).

► Grants and Tax Rebates in Europe , USA and Canada

► Additional Discounts on Energy Efficient appliances (from Manufacturers), Not in Iran


ROI on Green Building(Example)

► One Example• $11,900 added cost• $1000 added mortgage

payments per YEAR• $1,900 utility savings per

year• About $900 / year ROI

Example project for NetZEB


LEED and other standards

► Administered by U.S. Green Building Council (USGBC).

► Considered by many to be the de-facto standard for green home construction

► LEED-H is administered by approved network of Green Raters.

► Other standards exist• EnergyStar (U.S. EPA)• NAHB (National

Association of Home Builders).

• Others?


Summary – the Fundamentals

► Site selection

► Energy efficiency

► Water efficiency

► Sustainable materials• Recycled• Reclaimed• Local• Certified

► Demolition and construction waste management.


Summary

► Have to decide what’s important to you. Setting priorities and limits.

► Synergy and Holistic design – Look for opportunities to achieve multiple goals with one solution.

► Explore LEED but be open to other options too.

► You want something that you will love and which will enrich the community. This is why Architects are especially important.

► The Zero Energy House Project embodies all these principles and is at frontier of market-rate speculative house construction. Webcam image

April 13, 2009

8:21 AM

Making Progress

Documents

Meditch Murphey Architects A1 Sofeh Co. Isfahan, IRAN, Tel: (311)663 9087, Fax:(311)663 9088, Designing the Zero Energy House NetZEB Concepts