Kolbe Heritage Series: Specs, Testing Data & Idaho Fit

Specifications & Testing Data

What the Heritage Series Actually Is

Heritage is Kolbe's all-wood line: wood on the interior, wood on the exterior, no aluminum skin anywhere. It exists for one job — reproducing what was built before cladding existed — and Kolbe — the full name is still Kolbe & Kolbe Millwork Co., of Wausau, Wisconsin — is unusually good at it. Frames and sash come in pine as standard or in maple, knotty alder, vertical- or mixed-grain fir, Spanish cedar, alder, cherry, oak, white oak, mahogany, sapele, or walnut, with rarer species quoted on request.

The catalog is the traditional one: Traditional, Sterling, and Old World Classic double-hungs (the Traditional runs to 51-1/2" wide by 96-7/16" tall, with compression jamb liners so the sash tilt in for cleaning), crank-out, push-out, and inswing casements, awnings, direct sets, quarter- and half-round radius units, geometrics, and folding windows. Exterior casings are milled in period profiles — bull nose, beaded, flat — rather than snapped-on trim. Doors follow the same construction: swinging and sliding patio doors, folding doors, entrance doors, and commercial doors with transoms.

The exterior leaves the factory one of two ways. K-Kron II is Kolbe's three-step finish — a preservative immersion treatment, urethane primer, then an airless-sprayed topcoat in 40-plus colors — and it carries a 10-year film-integrity warranty. Or you take it primed and have it painted on site, which Kolbe requires within 60 days of delivery, two coats, three mils minimum.

In the lineup, Heritage sits alongside the clad-wood Ultra Series as Kolbe's two traditional lines, with the VistaLuxe WD Line covering contemporary design and the Forgent Series covering budget.

The Numbers That Matter

Wood is a poor conductor, so Heritage tests well for a frame this substantial. Kolbe's published NFRC data for Heritage casements with dual-pane LoE-366 and argon runs 0.26–0.30 U-factor at 0.18–0.22 SHGC; adding ThermaPlus room-side Low-E brings casements to 0.22–0.26 and a Traditional double-hung to 0.23. Direct sets reach 0.21–0.22 on ThermaPlus glass. Kolbe also rates Heritage with suspended-film Enthermal glazing down to 0.13, and those packages — along with several ThermaPlus configurations — are what earn the ENERGY STAR Northern and North-Central marks; base dual-pane does not.

SHGC spans 0.18 to 0.31 across Low-E argon packages: LoE-340 at the low end for a west-facing sunroom, LoE-270 ThermaPlus at the top for a north parlor that wants winter sun. On divided lites, remember that every muntin adds frame and subtracts glass; a six-over-one TDL sash will not test the same as a onelite. We quote the exact configuration so the NFRC label matches what design review approved.

Design pressure and air infiltration vary by style and size; a 51-inch-wide double-hung and a 24-inch casement are not the same animal. We confirm per unit and note it on the quote.

Where It Fits in Idaho — and Where It Doesn't

Boise's ten local historic districts — the North End, East End, Hyde Park, Harrison Boulevard, and Warm Springs Avenue among them — are Heritage country. The city does not permit vinyl in these districts, window replacement requires a Certificate of Appropriateness, and the guidelines say repair first, replace in kind second. Minor work is reviewed at staff level; a full replacement on a contributing structure can go to the Historic Preservation Commission. What the commission and staff look for is exactly what Heritage does: matching muntin patterns and widths, sash proportions, sill and casing profiles, and — on the Queen Anne and Colonial Revival homes along Warm Springs Avenue and the 1890s–1920s houses of the East End — wood you can see. A drawing set with the original profiles traced and the muntin layout dimensioned is most of the battle, and we prepare it as part of the quote.

Beyond the districts: Craftsman bungalows on the Bench, farmhouse restorations in Canyon County, and church, school, and civic work where a landmark standard applies. It is also the line for a new build that wants to look like it has always been there.

Where it is the wrong buy, and we will say so: any home where nobody will keep up an exterior paint schedule. Boise's high-desert sun — roughly 200 sunny days a year, about 11 inches of rain, and 30-degree daily swings — chalks and checks a wood finish faster than the humid Midwest the product is built in. The dryness that saves wood from rot punishes the finish instead. If you want the look without the ladder, Ultra Series delivers the same interiors and profiles behind extruded aluminum and passes design review in most cases. And on a standard 1990s subdivision replacement, Heritage is simply the wrong tool; see our wood and clad-wood guide for where each belongs.

Warranty and Service, Locally

Kolbe's Express Limited Warranty covers Heritage for 10 years on materials and workmanship, 20 years on insulating-glass seal failure for lites under 60 square feet, 10 years on K-Kron II against cracking, peeling, and flaking, and 5 years on factory interior finishes and on K-Kron color change. True divided lite glass is covered for 2 years — a genuine tradeoff we spell out before you order. Primers are not warranted, so a primed unit that is not topcoated on schedule is on the owner.

Because the exterior is wood, the installation and the first finish coat decide how the next 30 years go. Wood Windows Inc has installed and restored wood windows in this valley with our own employees since 1980 — 46 years and counting — and warranty calls on Heritage units we sell come to our Garden City shop, not to Wisconsin.

Have an original sash we can profile, or a design-review letter to satisfy? Request a quote on this page or call (208) 376-2200.

Last reviewed 2026-09-10 by Wood Windows Inc — (208) 376-2200