Specified to perform. Built to last.
The numbers below hold across every system. Where a project needs more — a specific Uw, a coastal pressure rating, a sound class — we engineer to it and document the result.
| Standard Uw (installed) | ≤ 0.28 |
|---|---|
| Triple-glaze Uw (installed) | 0.12 – 0.16 |
| Triple-glaze glass Uw | as low as 0.09 |
| R-value (standard) | R-4 |
| R-value (triple glaze) | R-8 to R-10 |
| Air infiltration | ~10% of allowable max |
| Acoustic (standard) | 34 dB |
| Acoustic (enhanced) | up to 50 dB |
| Design pressure | DP 65+ |
|---|---|
| Sustained wind load | 140 mph |
| Impact resistance | Large Missile Level D |
| Pressure rating | 65 PSF standard |
| Hardware rating | Oceanfront / salt-air |
| Locking | Multi-point, opposing direction |
| Testing standard | Air / Water / Structural |
| uPVC reinforcement | Full steel frame |
| Wood stability | 3-ply laminated, reverse grain |
A spec is only useful if you know what it's beating.
Every comparison below uses Henselstone's own tested figures against published industry references — not marketing math. Sources are linked under each chart.
What a U-factor of 0.28 means
U-factor measures how fast heat escapes a window — the lower the number, the better it insulates. Henselstone units install at 0.28 as standard, and triple-glazed units reach passive-house territory.
U-factor · Btu/h·ft²·°F · lower is better
Sources: ENERGY STAR / NFRC window criteria (EPA) · High-Performance Windows — DOE Building America · Passive House window guidance — PHIUS
What up to 50 dB of sound reduction means
Standard dual-pane windows cut roughly 26–28 dB of outside noise. Henselstone glazing ranges from 34 dB standard to about 50 dB with enhanced acoustic glass — the difference between hearing a busy street and near silence.
Sound reduction · dB (higher is better) · higher is better
Sources: Sound Transmission Class & window acoustics — general references
Independently certified, product by product.
Every certification below is active and verifiable in the NAMI public directory, with test documentation available per product.
| NI013728 series (.01–.05) | Glazed outswing side-hinged French doors — sidelites, transom, roundtop, archtop, wood panel · exp. 5/2028 |
|---|---|
| NI013721 series | Wood segmented glazed side-hinged doors · exp. 5/2028 |
| NI013037 series | Lift & slide wood sliding glass doors — standard sill, with/without load clip · exp. 3/2028 |
| NI012658 series | Hardwood push-out casements, incl. half-round · exp. 12/2027 |
| NI012657 series | Hardwood tilt & turn windows — single with center fixed, arched double, top-tilt with bottom fixed · exp. 12/2027 |
| NI012653 series | Hardwood fixed windows, incl. half-round and semi-circle tops · exp. 12/2027 |
| NI011128 | PVC lift & slide door · exp. 12/2027 |
| NI011127 series | PVC fixed windows · exp. 12/2027 |
| NI010029 | Impact-rated vinyl dual-action side-hinged glass door · exp. 6/2028 |
Tested, certified, and through real storms.
Ten years, fully transferable.
Coverage on materials, workmanship, and hardware — and because every wood and metal-clad unit is finished completely in the factory, the finish is covered too. The warranty transfers with the home.
| NAMI certification | 26 active certs — see series above |
|---|---|
| NFRC ratings | Per product, on request |
| Impact approval | Large Missile Level D (NI010029) |
| Warranty term | 10-year full, transferable |
Full certification documentation is available to specifiers on request.