Replacement windows in California must meet Energy Code limits for U-factor and, in many climate zones, solar heat gain coefficient (SHGC). Simple replacements are usually shown prescriptively; larger window changes or added glass area may need a performance model.
Projects we cover
What’s included
- Climate-zone requirement check
- Prescriptive or performance documentation
- Product spec review (NFRC ratings)
Do replacement windows need a Title 24 report?
They must meet code values; documentation requirements depend on your jurisdiction and whether glass area increases.
Which compliance forms are used?
Residential alteration CF1R forms or performance CF1R.
What documents do I need?
- Window schedule with sizes
- NFRC U-factor and SHGC values
- Elevations showing affected openings
Missing something? Order anyway — we’ll flag gaps and, where appropriate, use code-minimum assumptions with your approval.
How we prepare your report
- 01Plan & data intake
We review your plans for completeness — floor plans, elevations, sections, window schedule and mechanical notes — and flag anything missing before modeling starts.
- 02Climate zone & scope confirmation
We confirm the project’s climate zone from the site address using the CEC lookup, and the compliance scope (new construction, addition, alteration).
- 03Energy modeling
The building is modeled in CEC-approved compliance software, choosing the performance or prescriptive path that best fits your design.
- 04Technical review
Inputs are checked against the plans: areas, orientations, assemblies, fenestration, HVAC and water heating, PV and battery requirements.
- 05Delivery & revisions
You receive the signed compliance documents as PDF, ready to print onto the plan set, with included revisions for plan-check comments.
Frequently asked questions
Where do I find U-factor and SHGC?
On the NFRC label or the manufacturer’s spec sheet for the exact product.