Greenhouse gas emissions are the primary contributor to Earth’s warming temperatures. Every decade since 1880, global average surface temperatures have risen by 0.14 degrees Fahrenheit. However, the increase in the warming rate since 1981 has been nearly twice that.
Research indicates that energy use in the residential housing sector contributes to 20% of all GHG emissions in the United States. Building more energy-efficient homes is no longer enough if this country is to reduce its climate change impacts significantly. The net-zero home design may be the future for builders.
What Is a Net-Zero Home?
Net zero refers to something’s overall energy consumption. A home with net-zero energy produces more energy than it uses. Though the most basic route to getting there is to install a renewable energy system, reducing a building’s carbon footprint and energy usage often requires careful planning.
Zero Energy Ready Home
The U.S. Department of Energy implemented a voluntary program for net-zero home design certification called the Zero Energy Ready Home Program. Builders wishing to participate in ZERH must register as a partner. Partners construct homes that meet the program’s requirements, while verified partners utilize DOE-approved third-party organizations to certify the houses meet program requirements.
What Are the Requirements of ZERH?
Under ZERH, a net-zero home must meet structural and performance standards, including the following:
- Homes must be under the Energy Star Qualified Homes Program.
- Windows must meet Energy Star requirements, and insulation must adhere to the 2015 International Energy Conservation Code standards.
- The location of the ducts must be within the structure’s thermal and air barrier boundary or an area that provides similar performance benefits.
- The home must be certified for indoor air quality under the Environmental Protection Agency’s Indoor airPLUS Version 1.
- Water heater or hot water delivery systems must meet Energy Star standards for specific system types.
- All appliances must be Energy Star rated, including bathroom ventilation systems and ceiling fans.
- 80% of all lights in the home must be LED.
A net-zero home also meets the provisions of the DOE ZERH PV-Ready Checklist.
How Can Builders Create a Net-Zero Home Design?
Achieving ZERH certification requires planning and coordination to ensure the home meets the program’s standards. Here are 10 design tips to help you meet the established criteria.
1. Use a Building Design Software
CAD PRO and other similar software programs provide tools to help you create a ZERH design. Utilizing tools with options for tracking energy efficiency standards keeps you on target throughout the build.
2. Design With Solar in Mind
Solar panel systems that include battery storage are one of the most effective ways to create a net-zero home. Ensure your design is solar-ready, including appropriate roof space, load capabilities, exposure, and orientation.
3. Use a 2-Foot Grid for Framing
A two-foot grid creates continuous load capabilities from the base to the top. It also makes window installation easier and improves overall insulation. This grid size also reduces waste, as fewer wallboard cuts are needed.
4. Implement Advanced Framing Techniques
Advanced framing techniques also reduce waste produced and save on labor. Examples of these techniques include:
- Spacing wall studs, floor joists, and roof rafters 24” on-center
- Leaving out the headers in non-load-bearing walls
- Use top plates and single-lumbar headers when possible
- Make use of in-line framing
Local building codes may not allow all advanced framing techniques.
5. Use Engineered Wood
Engineered wood is stronger than natural wood. Using engineered timber also reduces waste and labor throughout the product’s lifecycle.
6. Select the HVAC Design Best for the Local Climate
An HVAC system can make or break efficiency in a net-zero home. Make sure you understand which design is appropriate for the climate you’re building in.
7. Install Ducts According to ZERH Specifications
Ensure you locate ducts in spaces that reduce exposure to temperature extremes. Horizontal-ducted units are often recommended, but other options can serve the same purpose.
8. Design Air Sealing Solutions at the Start
Your design plans should include solutions for sealing the structure to prevent drafts. This also reduces moisture buildup.
9. Use PEX for the Plumbing Manifold
A PEX design for the central manifold is flexible and efficient. It reduces energy usage for heating water and reduces hot water waste.
10. Keep It Simple
The most energy-efficient structures are usually the simplest designs. A box-styled house reduces waste at every stage, from construction to energy usage.
Who Can You Contact for Net-Zero Home Planning Solutions?
ESG Property Consultants’ founder, Matt Snyder, spent 30 years in the construction industry. He has expertise in residential construction and sustainability. If you need assistance with net-zero home planning, ESG Property Consultants can help you find the right solutions.