What Does a Compliance Margin Shortfall Mean on a CF1R?
The compliance margin is the gap between the energy budget and what your proposed design is modeled to use. At zero or better the design complies. A shortfall means the model sits over budget and something must change. The budget comes from a standard design that already carries every mandatory and prescriptive measure.
- Choose your report
- Upload your plans
- Pay securely
- Permit-ready report by email
A budget and a line
Section 150.1(b) says a house complies with the performance approach when the energy calculated for the proposed design is no greater than the budget calculated for the standard design by approved software. The margin is how far above or below that line your model falls. For a remodel the budget is long-term system cost (LSC) alone, and the design passes if every mandatory measure is met and total LSC is no higher than the standard design's.
Three figures in a new home
A new home is compared on source energy, on Efficiency LSC (space conditioning, water heating, mechanical ventilation and the self-utilization credit) and on Total LSC, which adds solar, battery, lighting, demand flexibility and plug loads. Each is its own comparison.
What spends margin
The standard design copies your building and applies the prescriptive package, so every departure is charged against you. The manual's own example is a gas furnace modeled where the package assumes a heat pump, which raises heating source energy sharply. A water heater less efficient than the package's heat pump unit, and glass beyond 20 percent of floor area, work the same way, because the standard design caps its window area at that share.
What cannot rescue a shortfall
Lighting and appliance energy is not eligible for trading. Solar by itself does not touch Efficiency LSC. A battery of at least 5 kWh paired with solar lets part of the credit count toward efficiency, a modest help for a marginal gap, and a standalone battery gets none.
Reading your own result
A margin well above zero needs no action. A small gap often closes with one equipment or glass change. A large gap needs a rethink, and the page on what to change lists the levers. See also how to read a CF1R, prescriptive versus performance reports and why a design fails. Our residential reports include the model.
Common Title 24 Questions
- What is Title 24?
- Do I need a Title 24 report?
- How much does a Title 24 report cost?
- How long does a Title 24 report take?
- What is included in a Title 24 report?
- What plans do I need to upload?
Frequently Asked Questions
It means the design as modeled exceeds its budget, so it cannot be certified as compliant until the design or the model changes.
Not in the same sense. A prescriptive report checks each requirement one by one, and a single miss sends the project to the performance route.
Explore Failed Compliance
- What Happens If You Have No Title 24 Report?
- My Design Does Not Comply: Which Changes Bring It Back?
- Why Does a Title 24 Design Not Comply?
- Title 24 Compliance in California
- Can a Building Department Approve a Permit if the Report Says Does Not Comply?
View all Failed Compliance guides → · Permits and Compliance · Title 24 guide