Search Backing sky grass
Office of Sustainability and the Environment
Green Building Green Building
ZNE Guide for New Construction - Residential

ZNE Guide for New Construction - Single Family

Zero net energy (ZNE) homes are utility grid connected homes that are designed and operated so efficiently that they are able to produce as much energy as they need to operate on an annual basis with clean, renewable energy. The Santa Monica Residential Zero Net Energy Guide for New Construction focuses on the general elements of ZNE homes and provides links to the specific details and requirements of Title 24 (energy code) and Home Energy Rating System (HERS) verification (field verified and tested).

ZNE Guide Cover

 

  • ZNE homes are more comfortable and healthier due to passive design strategies such as natural ventilation and daylighting. 
  • ZNE homes lower operational and maintenance costs and reduce emissions, while providing homeowners with greater peace of mind.

The following steps are recommended to ensure successful ZNE construction:

STEP 1 - SET GOALS:

There is no single ZNE recipe; many efficiency measures and combinations of measures can help a home achieve ZNE.Discussions with your project team and simple energy models can help determine which ones are most appropriate for your home. A homeowner may opt to just meet the code requirement. With the many paths for getting to zero, it’s important to understand the options and set goals around daily performance. For example, consider the trade-offs, like mechanical window controls to open and close windows at set hours, as opposed to manual windows, which come at a lower upfront cost, but require proper occupant use. 

STEP 2- TRIM ENERGY LOADS:

Santa Monica’s warm, temperate climate with moderate wind provides opportunities for nature to passively heat, cool, ventilate, and even light your home with the right site and design. Attention to how the home is oriented and whether windows take advantage of natural light and breezes impact energy performance. These decisions about passive solutions and envelope early in the design process  can significantly minimize energy use.

Many resources are available to designers to help analyze your micro-climate and building configuration. Early design analysis software and other evaluation tools can be used to analyze site characteristics and compare design alternatives without significant investment in energy modeling. Without these tools, some simple rules can be followed to meet similar results.

Envelope:  ZNE starts with a well-insulated and sealed building envelope (enclosure) to minimize heat transfer between the conditioned and unconditioned spaces. This reduces the energy needed to heat and cool a house. Attention must be paid to the details and transitions during construction to ensure maximum comfort for the home owner.

Passive Heating, Ventilation, Cooling and Lighting:  Consider designs that use passive ventilation to move air through the home. Use the house orientation to take advantage of cool morning or evenings winds. Deep roof overhangs, exterior window shades, and vegetation can block the sun during the hottest times of the day. Or, study if a thermal mass is right for the design.

STEP 3 - SELECT EFFICIENT EQUIPMENT:

Many efficiency measures and combinations of measures can achieve ZNE. Discussions with your project team and simple energy models can help determine which ones are most appropriate for your home.

Lighting: Daylighting can provide access to natural light and a connection to the outdoors for homeowners. As a free resource, daylight can be supplemented with visually pleasing, high efficacy light fixtures and lamps that can be used for task lighting a work surface or general illumination at night. Lighting controls can also ensure lights are only on when they are needed.

HVAC: Once the envelope design goals are established, identify home heating, ventilation, and air conditioning needs and equipment in various spaces. Energy modeling can assist with the exercise of selecting high performance equipment. Also, consider duct design improvements such as locating ducts in the conditioned space to minimize heat transfer.

Domestic Hot Water: The best way to reduce hot water energy consumption is to reduce the demand by specifying efficient, low-flow fixtures in the kitchen, bath, and laundry rooms. This will also decrease overall water use. Once the hot water demand has been reduced, identify the most efficient way to heat, store, and distribute the hot water.

Plug Loads: Even in very efficient homes, plug loads, which are devices plugged into wall outlets, can represent 50% of total annual energy use. Much of this energy use occurs when the home is unoccupied and devices are left plugged into the outlets. Selecting energy efficient equipment and appliances is easier than ever with the popularity of the ENERGY STAR® label and the rise of plug controls  

STEP 4 - ADD RENEWABLE ENERGY:

Once energy consumption has been minimized, installing on-site renewable energy systems can be sized to meet the ZNE goal. Santa Monica has an average of 281 days of sunshine a year, making it optimal for producing energy on-site with solar photovoltaic (PV) panels. The less energy the home uses, the fewer PV panels required, and the lower the price.

STEP 5 - VERIFY CONSTRUCTION:

Once energy consumption has been minimized, installing on-site renewable energy systems can be sized to meet the ZNE goal. Santa Monica has an average of 281 days of sunshine a year, making it optimal for producing energy on-site with solar photovoltaic (PV) panels. The less energy the home uses, the fewer PV panels required, and the lower the price. when using an integrated design process. Use the HERS standard in the design phase to identify energy efficiency measures for your home. Energy modeling can be used to test those measures’ efficiency in an interactive away.

For more information see the Santa Monica Residential Zero Net Energy Guide for New Construction PDF.

Last updated: Tuesday, 04/25/2017

ZNE Guidelines for New Construction

 ZNE Guide Cover
Download (pdf)
 

ZNE Cost Effectiveness Study 

 ZNE Cost Effectiveness Study
Download (pdf)
 

Matrix 2.0 Alternative Water Guidelines 

 Matrix Document Banner
download (pdf)
New roadmap for decentralized, alternate water supplies - indoor and outdoor non-potable water regulations streamlined for rainwater, graywater, stormwater, blackwater use.


Solution Finding for Net Zero Water 

Sustainability experts from across the nation convened to explore statutory, technological, and engineering barriers to the widespread implementation of water recycling and reuse systems in commercial and residential buildings.
Net Zero Water Booklet
download (pdf)

High Performance Buildings Study


Designing high performance green buildings literally build our sustainable city commitments into the fabric of the community.  
Check out this study analyzing the costs of a prototypical mixed-use project.

High Performance Building Study Cover
download (pdf)



 

City of Santa Monica © 2017

Santa Monica Office of Sustainability and the Environment
1685 Main St., Santa Monica, CA 90401 · (310) 458-2213 · TTY (310) 917-6626