Windows for Hot Central Valley Summers: What the Energy Label Means

Short answer: Window energy labels from the National Fenestration Rating Council (NFRC) report performance numbers such as U-factor and Solar Heat Gain Coefficient (SHGC). In hot Central Valley summers, understanding those numbers — and ENERGY STAR guidance for your climate — helps you compare options before you buy. Fletcher offers free on-site measurements and quotes so you can match products to your home.

Why do Central Valley summers make window choice matter?

The Central Valley sees long, hot summers. Windows affect how much heat enters a room through glass and frames. That does not mean every home needs the same product — it means comparing labeled performance (and shading options) is worth a few minutes before you order.

Fletcher is a family-owned showroom in Turlock serving the Central Valley, including Modesto. We carry choice window brands such as Milgard, Premium Windows, and Jeld-Wen, and can discuss patio sliders and Graber Blinds for shading. See the windows page for current options.

What is an NFRC label?

The NFRC develops energy performance ratings for fenestration products (windows, doors, and skylights). A label that uses NFRC ratings gives apples-to-apples numbers so you can compare products from different manufacturers.

Official overview: NFRC — About.

What does U-factor mean?

U-factor describes how well a window insulates — how readily heat flows through it. Lower U-factor means less heat transfer. NFRC publishes the rating methodology and consumer explanations; start with NFRC’s educational materials rather than marketing claims.

Reference: NFRC (see their consumer / ratings resources for current definitions).

What does SHGC (Solar Heat Gain Coefficient) mean?

SHGC measures how much solar heat passes through a window. Lower SHGC means less solar heat gain. In a hot climate, that number helps you understand how aggressively a glass package blocks solar heat compared with another option.

Again, use the NFRC definitions as the source of truth — not a salesperson’s shorthand.

How does ENERGY STAR fit in?

ENERGY STAR is a U.S. EPA / DOE program that sets efficiency criteria for products, including windows, for different climate zones. ENERGY STAR qualification is separate from reading the raw NFRC numbers, but both help you compare.

Useful starting points:

• ENERGY STAR — Windows, Doors, and Skylights
• ENERGY STAR — Climate zones / regional guidance (follow their current zone maps and criteria)

We do not invent savings percentages or “guaranteed bill reductions” here. If a manufacturer publishes a number, ask to see the source.

How should I compare brands at Fletcher?

At the showroom, compare:

1. Labeled performance (U-factor, SHGC, and other NFRC ratings on the product literature)
2. Frame and glass options for your openings
3. Warranty and look from brands such as Milgard, Premium Windows, and Jeld-Wen
4. Shading (e.g. Graber Blinds) if solar heat is a concern

“Premium” on this site refers only to the Premium Windows brand name — not a generic quality claim.

What happens at a free window measurement?

Fletcher offers free quotes and free on-site measurements at your home or job site. You can also visit 1720 Paulson Rd, Turlock, CA 95380 (Monday–Friday 7am–4pm, closed 12pm–1pm for lunch). Serving Turlock, Modesto, and the Central Valley — including a Modesto showroom coming soon.

Serving Modesto and nearby areas →

Window energy label FAQs

What is U-factor on a window label?

U-factor measures how well a window insulates. Lower U-factor means less heat transfer through the window. Definitions are published by the National Fenestration Rating Council (NFRC).

What is SHGC?

Solar Heat Gain Coefficient (SHGC) measures how much solar heat passes through a window. Lower SHGC means less solar heat gain — useful to understand in hot summers. See NFRC for the official definition.

Does Fletcher offer free window quotes?

Yes. Fletcher provides free quotes and free on-site measurements for window projects, with choice brands including Milgard, Premium Windows, and Jeld-Wen. Visit /windows or call (209) 632-3610.

Next step

Bring your questions about labels and brands to the showroom, or request a free measurement. We’ll walk through options without inventing numbers that aren’t on the label.