Specifications & Testing Data
| Frame material | Wood core with Perma-Shield vinyl exterior cladding |
|---|---|
| U-factor (NFRC) | 0.26 – 0.31 |
| Solar heat gain coefficient (NFRC) | 0.26 – 0.33 |
| Design pressure (DP) rating | Varies by unit and size — commonly DP 30–50; verify per configuration |
| AAMA performance class | Certified to AAMA/NAMI standards; class varies by unit |
| ENERGY STAR zones | Northern, North-Central |
| Glass options | Low-E4, Low-E4 SmartSun, Low-E4 Sun, Tempered, Triple-pane (select units) |
| Available styles | Tilt-Wash Double-Hung, Casement, Awning, Gliding, Picture, Bay & Bow, Specialty shapes |
What the 400 Series Actually Is
The Andersen 400 Series is Andersen's flagship clad-wood line: a solid pine core wrapped in Perma-Shield vinyl cladding on the exterior. That construction is the whole story — wood's insulation and interior beauty, with an exterior that never needs paint. Andersen has built windows on this recipe since the 1960s, which is why you'll still find working Perma-Shield units in Boise North End homes from the Carter administration.
It sits above Andersen's 100 Series (Fibrex composite) and 200 Series (simplified wood) and below the architectural A-Series/E-Series lines. For Treasure Valley homeowners who want a "buy once" window, the 400 Series is usually the first product we put on the table.
The Numbers That Matter
Every 400 Series unit carries an NFRC label with tested — not advertised — ratings. Across common configurations with Low-E4 dual-pane glass, U-factors run roughly 0.26 to 0.31 and SHGC from 0.26 to 0.33. Casements and awnings, which compress their seals like a refrigerator door, test at the better end; tilt-wash double-hungs at the higher end. Most configurations qualify for ENERGY STAR in the Northern zone that covers Idaho.
Three glass packages cover Idaho use cases:
- Low-E4 — the default; balanced U-factor and visible light.
- Low-E4 SmartSun — cuts solar heat gain roughly a third further while staying visually clear. Our standard recommendation for west-facing Treasure Valley elevations.
- Low-E4 Sun — tinted, for extreme exposure like unshaded foothills glass.
Where It Fits in Idaho — and Where It Doesn't
The 400 Series earns its cost on homes where appearance and longevity both matter: North End and East End historic homes (the clad-wood profile passes design review where vinyl can't), custom and semi-custom builds, and any home you plan to keep for more than a decade.
It's the wrong answer for some jobs, and we'll say so: on a rental or a flip where every dollar counts, a quality vinyl window like Milgard delivers the required energy numbers for a lot less. That's the advantage of a multi-brand dealer — we can put both quotes side by side and let the math talk.
Warranty and Service, Locally
Andersen covers glass for 20 years and non-glass components for 10, transferable between owners. The part that matters more in practice: as an authorized Andersen dealer, Wood Windows Inc handles warranty service ourselves, with our own employees, out of Garden City. If a sash ever fogs in year 12, you call us — not an out-of-state call center — and the people who installed the window fix it.
Want per-unit NFRC numbers for your configuration, or a side-by-side against Marvin or Milgard? Request a quote on this page or call (208) 376-2200.
Frequently Asked Questions
Is the Andersen 400 Series worth the price over builder-grade vinyl?
For most homeowners planning to stay put, yes. The 400 Series costs roughly 40–80% more installed than mid-tier vinyl, but the wood core with Perma-Shield cladding has a decades-long track record — the 400 Series has been in production since 1966 in various forms — versus a realistic 15–20 years for builder-grade vinyl in Idaho's climate. It also looks like a real window, which matters at resale.
What U-factor does the Andersen 400 Series achieve?
With standard Low-E4 dual-pane glass, most 400 Series configurations test between 0.26 and 0.31 NFRC U-factor depending on style and size — casements test better than double-hungs. That meets the U ≤ 0.30 target we recommend for Treasure Valley homes on most configurations. Exact per-unit numbers are on each window's NFRC label, and we quote them line by line.
Does the 400 Series need painting or staining?
Outside, no — the Perma-Shield vinyl cladding is the finish, and it's the reason 1970s-era Perma-Shield units are still in service. Inside, the natural pine can be painted, stained, or ordered prefinished in white.
How long is the wait for Andersen 400 Series windows in Idaho?
Typically 4–8 weeks from order to delivery depending on configuration and season. As an authorized Andersen dealer we order factory-direct, and our in-house crews typically install a full house of windows in one to two days once they arrive.
Sources & Testing Data
Last reviewed 2026-07-04 by Wood Windows Inc — (208) 376-2200