Sizing a PV System for the 2022 Energy Code

The 2022 California Energy Code, which takes effect Jan. 1, 2023, has a new requirement for renewable energy systems for multi-family and non-residential projects. The calculation is based on conditioned floor area, building use, climate zone and other factors. Although the requirement is prescriptive, almost all projects will need to include PVs and batteries in order to meet the thresholds for reducing carbon emissions.

Here’s a 6-minute video where we walk through the Prescriptive method for sizing a standard baseline PV system, the results of which can be used to inform the design team of PV parameters and constraints early in the design process. 

For your specific project be sure to review the code language as to allowable exceptions, especially if it appears your project may not receive much sunlight, or may have a small solar accessible roof area.

More questions? Reach out: andy@inbalancegreen.com

A Peak into Green Building Classes - For High Schools!

We know that the future of energy efficiency and sustainable building depends on new people entering this field, whether transitioning from adjacent careers or brand new to the work force. The Tri-County Regional Energy Network (3C-REN) has scores of course offerings for designers, builders and other industry professionals, but has just added a new program to the mix: Green Building for high school students. At In Balance Green Consulting, we’ve had the pleasure of providing these introductory 1-hour classes, which not only supports new career paths for these youth, but also wowed our team with the hands-on learning these young people are offered.

Career Technical Education has seen a resurgence of investment, and it’s been exciting to see the ‘classrooms’ for many of these programs. With indoor shop space and support yards, students ages 14 – 18 are frequently building parts, or all, of a tiny home, including pouring concrete, framing walls and roofs, wiring lights, installing plumbing and HVAC, hanging drywall, installing siding, and even finishes in some cases.  Other courses cover drafting, design and engineering, alongside related fields like machining and wood shop.

In our “Introduction to Green Building” class, we review the energy and resources that go into a building, discuss the potential negative impacts of construction and suggest ways to mitigate those impacts. We talk about design, highlighting traditional building methods and contemporary climate-responsive projects, then talk about products that are low-emitting or use recycled content, for example. We pass around product samples, such as wool carpet, recycled glass counter tops, rigid insulation, and bamboo panels.

There are some very impressive programs throughout the central coast! To highlight a couple of rockstar programs (in their own words):

ACE Charter High: Architecture Construction and Engineering (ACE) Charter High School in Camarillo provides a scientific, technical, analytical, and liberal arts based high school experience through progressive and collaborative teaching practices. Through career pathways, ACE students explore a rigorous, contextual, project-based curriculum that prepares students for lifelong learning as well as direct-entry into college, professional apprenticeship programs, or a technical career.

Santa Maria CTE: The Santa Maria High School District has a Career Technical Education Center that just opened in 2021. The facilities are state-of-the-art, bringing together students from three different high schools throughout the district. The career focus is to ready students for apprenticeship programs or to community colleges for ongoing education and certifications.

Thousand Oaks High School: TOHS has a Residential and Commercial Construction pathway. Students learn the basics in 15 different trades, which will increase their opportunities for hiring in the future, and are introduced to industry standard techniques to be competitive in future job interviews. They compete in building competitions to demonstrate construction skills, develop student leadership and teamwork. Each unit of study provides students a hands-on learning experience to reinforce the concepts in order to further the learning and skill development. 

Do you know a high school program that would be interested in a guest speaker on green building? Reach out and let us know!

West Cox Cottages Achieves GreenPoint Rated Certification

West Cox Cottages is an innovative, all-electric, affordable housing project in Santa Maria serving people with special needs. It includes 12 single-story duplexes and quadplexes with 30 total rental units, a common space with a computer media center, laundry facilities, and an onsite caretaker. In Balance Green Consulting worked with the Housing Authority of the County of Santa Barbara (HASBARCO), consulting on energy optimization, photovoltaic (PV) sizing, GreenPoint Rated certification, and California Tax Credit Allocation Committee (TCAC) documentation.

Aerial of West Cox Cottages, Santa Maria

The project achieved its GreenPoint Rated certification by incorporating important features that improve energy and water efficiency, enhance indoor air quality, support resource conservation, and promote livable communities. Identifying GreenPoint certification early on helped guide the design process, ultimately leading to the decision to install Sanden Heat Pump Water Heaters, Fujitsu ductless mini-splits, and a 123.75 kW PV system.

One unique element of this project is that there were two separate builders. Atlas Performance Industries, Inc. (API) built the units as modular units at their facility, then transported them to the project site where the second builder team, Halsell Builders, took care of on-site construction. This method of modular construction provides benefits in the speed of construction, limiting weather delays, decreasing delivery trips to the job site (reducing overall transportation emissions), storing fewer materials on site, and causing less disruption to the surrounding neighborhood during construction.

Pre-fabricated parts into a whole

The now occupied West Cox Cottages project serves as a great example for how to prioritize all-electric features in multi-family housing, while pursuing GreenPoint Rated certification to build a better home for all occupants. Congratulations to the team!

Harry’s House: Best Practices in Radon Mitigation

Are you familiar with the health impacts of radon and the best practices for mitigating its impact on building occupants? Radon is a naturally occurring radioactive gas – colorless and odorless - that comes from the breakdown of radioactive elements in soil and rocks. Without proper mitigation, the gas can enter buildings and have serious impacts on occupant health. Radon is known as the second leading cause of lung cancer behind smoking.

How do you know if you’re in an area where radon exposure is a concern? The Environmental Protection Agency (EPA) provides a map (left) showing radon zones by county.

Zone 1 has the most severe radon levels, although homes with elevated levels have been found in all areas. This is why, regardless of location, all homes should be tested. We can see from the map that in California, the most affected areas are in Santa Barbara and Ventura counties. For GreenPoint Rated (GPR) projects, radon mitigation is required for projects located in Zone 1 and recommended for Zones 2 and 3.

One of In Balance’s GPR projects, “Harry’s House”, is a multi-family senior affordable housing project in Santa Ynez (Zone 1). On recent site visits, we got a chance to look at some of the radon mitigation strategies being put into place. So, what does this look like?

The EPA provides Model Standards and Techniques for Control of Radon for various building types. For our GPR projects, we focus on the guidelines for new residential buildings, but the EPA also provides guidelines for other project types. See the EPA Radon Standards of Practice website for more information.

Step 1: Lay a perforated pipe in a four- to six inch continuous layer of coarse gravel under the foundation slab or on the crawlspace floor. Here, the project is using a 12” radon venting mat rolled out in a waffle pattern. A stub out for the vertical venting pipe has been placed.

Step 2: Place course gravel over radon venting mat. Lay continuous vapor barrier (6 mm minimum) over gravel – taped and sealed. Concrete will be poured directly onto vapor barrier.

Step 3: Connect the horizontal perforated pipe(s)/venting mat to a gas-tight, solid 3-4” pipe(s) running vertically from slab to the attic and through the roof for passive sub-slab/membrane depressurization. Use mechanical vent fan as required.

Other best practices

·      Seal all penetrations or cracks in the slab, foundation, or crawlspace floor with caulk or adhesive sealant.

·      Provide an electrical receptacle in the attic or outside the building for the future installation of a fan (for active depressurization).

·      Test for radon after construction. This test can occur prior to occupancy or after occupancy. For GPR, the test must be completed by a Certified Tester as identified on the California Department of Public Health (CDPH) website. Home test kits are also widely available.

·      If the test results are greater than 4 picocuries per liter (pCi/L), install onto the vent pipe an in-line continuously operating fan for active depressurization.

Using these best practices during construction can go a long way in ensuring the health and safety of building occupants. We recommend testing and implementing appropriate strategies even if it isn’t necessarily required by a certification program.