In today’s day and age, state and local authorities place a lot of emphasis on environmental conservation, especially when it comes to new construction and remodeling activities. Such projects typically have to meet multiple codes and standards to get the required permits. Two of these are the Building Energy Efficiency Standards (aka Title 24), and the California Green Building Standards Code (aka CalGreen). Both codes deal with energy and resource conservation, and a basic understanding of these standards will go a long way in helping you get your permits, shaving money off your energy bills, and nudging your building closer to the zero net energy future.
To navigate through these two codes successfully, you must understand their intent and how they apply to your project.
What is CalGreen and how does it affect my project?
CalGreen aims to reduce the environmental impact of construction. To this end, the code regulates the use of energy, water, and materials during and after construction. CalGreen applies to all new residential buildings, as well as any additions or alterations that would increase the building’s conditioned area, volume, or size. The guide below summarizes CalGreen’s mandatory requirements.
Drainage and Grading
CalGreen requires the construction site to be adequately graded and stormwater drainage to be properly designed. This is important for two reasons: to prevent soil erosion in and around the construction site; and secondly to avert the ingress of stormwater into your buildings. Exceptions are allowed for modifications that do not alter the existing grading and drainage plans. In most cases a detailed site survey would be required to ascertain both the existing and proposed grading and drainage plans.
Residential homes with attached private garages must be able to accommodate charging stations for electric vehicles (EVs). Per CalGreen, each such dwelling unit must have:
a raceway for a dedicated 208/240-volt branch circuit from the service panel to an enclosure near the charger
service panels capable of receiving a 40-ampere dedicated branch circuit
space for an overcurrent protective device
It is advisable to hire a licensed professional to perform all the electrical work per the relevant guidelines.
Water Conservation and Efficiency
Droughts are a major problem in California, and to promote water conservation, CalGreens outlines performance criteria for water closets, urinals, showerheads, and faucets. These may seem like minor technicalities, but non-compliance with any of these criteria may lead to a rejection of your permit application. All residential developments with over 500 square feet must meet either their local or statewide water efficient landscape ordinance, whichever is more stringent.
To stop rodents from getting inside your building, all spaces around openings in the bottom plates of exterior walls must be closed with cement mortar, concrete masonry, or other methods acceptable to the local enforcement agency.
Construction Waste Reduction
CalGreen requires 65% of all nonhazardous waste not arising from excavation or land clearing to be recycled and/or salvaged. Either method below can be used to meet this requirement:
- submitting an acceptable waste management plan,
hiring a waste management company that can verify compliance with this clause, or
complying with a more stringent local ordinance
A local enforcement agency may exempt a project from this requirement if diversion or recycling facilities are not reasonably accessible.
Recycling by Occupants
Occupants of buildings with 5 or more dwelling units must have access to an area for the depositing, storage and collection of non-hazardous materials, such as:
metals for recycling
Operation and Maintenance Manuals
Once the project is ready for its final inspection, maintenance and operation manuals for the building’s systems shall be produced. A licensed and experienced contractor will be able to provide such a manual to satisfy the inspection authorities.
Pollutants and Volatile Organic Compounds (VOC)
In an effort to reduce the admission of harmful VOCs into your building, GalGreen requires that:
- gas fireplaces or wood and pellet stoves installed in your building must be certified to meet the emission limits, in addition to complying with the local ordinances
- all air intake and distribution component openings of HVAC systems must be covered using an acceptable method during construction
- adhesives, sealants, caulks, paints, and coating used in construction must comply with statewide VOC standards, as well as local, regional, and statewide air pollution or air quality management district rules, whichever are more stringent
CalGreen’s VOC reduction measures also extend to a variety of interior finish products, such as carpets, resilient flooring, and composite wood materials. Most of these items will have to meet the most stringent of the relevant state, regional, or local ordinances.
To prevent moisture penetration, CalGreen requires a capillary break to be provided with vapor retarders in direct contact with concrete. Talk to your contractor and ensure this capillary break is provided in all your concrete slab foundations or floor slabs.
In wood, moisture often leads to rotting and is a common cause of dangerous structural failures. To avert such tragedies, CalGreen bans building materials with visible signs of water damage from being used in construction. For example, framing members that comprise wall and floor assemblies must have a moisture content of less than 19%. Moisture content must be measured before installation; in floor and wall framing members, random moisture readings must be performed at least 3 times by the approval agency.
Indoor Air Quality
A big chunk of CalGreen is dedicated to reducing VOCs in interior finishes. Good indoor air quality is vital to the health and well-being of a building’s occupants, which is what CalGreen regulations aim to achieve. To enhance the quality of indoor air, CalGreens calls for fans or mechanical insulation inside each bathroom in a dwelling. These mechanisms must be ENERGY STAR compliant and require humidity controls.
A poorly sized HVAC system is wasteful and incapable of creating a comfortable environment in your home. CalGreen requires all HVAC systems and their ductwork to be sized according to approved manuals, such as Manual J, Manual D, and ASHRAE. Further, HVAC units must be selected based on ANSI/ACCA 3 Manual S - 2014 or equivalent, approved methods. A licensed HVAC contractor must establish the appropriate size for your HVAC system based on these methods.
CalGreen Compliance Documentation
Proving compliance with CalGreen is a requisite for getting your building permit. You may do this by showing relevant elements of compliance on:
- construction documents
builder or installer certification
inspection reports, or
other methods acceptable to your local building department
Hiring an experienced and licensed team of engineers and contractors will help you in getting the required compliance documentation in order without unnecessary hassles.
How does Title 24 affect your project?
Title 24, officially the Building Energy Efficiency Standards for both residential and non-residential buildings, outlines energy and water efficiency, as well as indoor air quality requirements for all new buildings, additions, and alterations. Having met these mandatory requirements, your project may comply with Title 24 via the prescriptive or performance options, both of which are described below. Our engineers at Design Everest can make your project compliant via either method. Contact us at (877) 892-0292 email@example.com to discuss your project and receive a quote today.
Regardless of the building type or compliance approach, Title 24 requires all projects to meet certain criteria. These cover building systems, building envelope, and solar power generation systems.
The following devices must be certified to the California Energy Commission (CEC):
power distribution, and
pool and spa systems
Many of these systems also have to comply with the Appliance Efficiency Regulations and meet the efficiency criteria specified in Title 24.
Pilot lights are prohibited in all natural gas systems, except household cooking appliances without an electrical connection if the pilot light consumes less than 150 BTUs per hour.
A building’s envelope components such as glazing, insulation, sealants, and roofing materials are subject to certification and performance criteria.
Glazing has to be certified to the CEC and must meet Climate Zone-specific values for:
- resistance to heat flow (U-Factor)
solar heat transmittance (Solar Heat Gain Coefficient), and
Insulation must achieve the specified heat flow resistance values (R-values), while roofing products have mandatory parameters for thermal reflectance and emittance, among others. Liquid-applied roofing products have to be tested for elongation, tensile strength, permeance, and cracking.
To prevent air leakage, all joints, penetrations, and openings that could allow air in or out of the building must be adequately sealed.
Solar Power Generation Systems
The 2016 version of the Building Energy Efficiency Standards requires most types of buildings to provide a solar area - a space where future solar systems can be installed. Effective January 1st, 2020, the requirements are set to become even more stringent - the new adoption of Title 24 calls for all low-rise residential buildings to be equipped with photovoltaic energy generation systems.
Besides the universal requirements, various types of buildings have specific criteria they must meet to comply with Title 24. These provide more specific guidance related to a building’s systems and envelope.
Title 24 Prescriptive Option
The prescriptive option calls for the use of methods and materials of proven efficiency. Projects choosing to comply using this approach must adhere to all requirements for the appropriate Climate Zone, including those found in Table 150.1-A of the Building Energy Efficiency Standards. The requirements specify the properties of insulation, radiant barriers, space conditioning systems, ventilation systems, water heaters, and roofing products. They also impose design criteria on glazing and offer several ways to achieve adequate shading.
Despite its rigid nature, the prescriptive approach still offers a bit of flexibility by offering more than one compliance option for some building elements.
Title 24 Performance Option
Another path to Title 24 compliance is via the performance standard. Using this approach, the project’s design team can use methods and materials of their choice, as long as the building meets its energy budget - the sum of Time Dependent Valuation (TDV) energy for space conditioning, mechanical ventilation, water heating, and lighting. The mandatory requirements described earlier remain in place with this approach.
How We Can Help
If you’re not feeling any better about Title 24 and CalGreen, we understand. Their requirements are complex and overwhelming.
That’s why our team of engineers is ready to give you a helping hand. With 14+ years in the industry, we know these codes in and out. We will guide your project’s design to compliance with these, and any other applicable regulations, to make sure that you get your permit quickly and reap the benefits of an energy and resource-efficient building. To find out more, call us at (877) 892-0292 or send your inquiry to firstname.lastname@example.org for a FREE consultation and quote.
*Note: The content published above was made in collaboration with members of Design Everest.
You must have an account to comment on the post. Register with us if you are an AEC professional!