Water penetration resistance (AS 2047 windows/doors)
AS 2047 water-penetration-resistance test sprays water on a window at static wind pressure (150-650 Pa). Result is on the permanent performance label.
Ask Chalkline about this →Water penetration resistance under AS 2047:2014 is the performance rating measuring a window’s or external glazed door’s ability to resist water ingress under wind-driven rain conditions, expressed as the maximum static air pressure (in Pascals) at which the unit can hold off water spray for 15 minutes without internal leakage. The rating is tied to the site’s wind class under AS/NZS 1170.2 (N1-C4) and printed on the permanent performance label that AS 2047 requires every compliant window to carry. Verified per AS 2047:2014 (2026-05-16).
Test method (summary):
- Sample window mounted in a sealed test rig.
- Water spray applied at a uniform rate over the external face (typical 5 L/min per m² of exposed area).
- Static air pressure applied behind the window via blower, simulating wind-driven rain.
- Pressure raised in steps (150, 250, 350, 450, 550, 650 Pa typical) and held for 15 minutes at each step.
- Test ends at the first sign of water penetration past the internal weather seal or onto interior surfaces.
- Rated pressure: the highest pressure at which the unit held the water for 15 minutes.
Pressure ratings tied to wind classes:
| Wind class | Site exposure | Minimum water resistance |
|---|---|---|
| N1 | Sheltered residential | 150 Pa |
| N2 | Typical residential | 250 Pa |
| N3 | Open residential or some commercial | 350 Pa |
| N4 | Exposed sites, cyclone fringe | 450 Pa |
| N5 | High wind sites | 550 Pa |
| N6 | Severe wind | 650 Pa |
| C1-C4 | Cyclonic regions | 650+ Pa, design-specific |
(All current per AS/NZS 1170.2 mapping into AS 2047.)
Reading the AS 2047 performance label:
A compliant window carries a permanent label (typically on the inside of the head or a sash edge) showing:
| Field | Value |
|---|---|
| Manufacturer | Name and address |
| Date of manufacture | Year/month |
| Wind rating | e.g. N3 |
| Water penetration rating | e.g. 350 Pa |
| Air infiltration rating | e.g. 1.5 L/s/m² at 75 Pa |
| AS 2047 compliance | Reference to the standard |
Builders should retain photographs of the labels as part of the as-built record. Loss of the label disconnects the window from its tested performance and complicates warranty claims or insurance investigations after a leak event.
Common water-penetration failure modes:
| Cause | Where leakage appears |
|---|---|
| Wind class mismatch: window rated N2, site is N3 or above | Failure under any major wind event |
| Sill flashing missing or compromised: water bypasses the window altogether | Below the sill, internal wall cavity |
| Counter-flashing/jamb seal poor: water tracks down the jamb | Internal corners at the head/jamb intersection |
| Frame distortion during installation: window installed out-of-plane, water seals don’t engage | At the seal line of the affected sash |
| Damaged or perished gaskets: rubber bulb seals harden in UV | Sash perimeter |
| Drainage holes blocked: water sitting in the frame can’t escape | Sill area, exterior face |
Test vs in-service:
The AS 2047 water test is factory laboratory testing of new units. In-service performance can degrade due to gasket aging, sealant failure, framing distortion, and damage. Australian construction practice is to:
- Specify a wind class with margin (rate one class above the calculated minimum if budget allows).
- Use AS 4773 (low-rise residential) or AS/NZS 4284 wider-scope testing for unusual or high-performance assemblies.
- Re-test or replace gaskets every 10-15 years in coastal or exposed sites.
Also known as: water test pressure; AS 2047 water rating; static-water test; wind-driven-rain rating.
Category: Testing.
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Last updated: 2026-05-16. Verified: 2026-05-16. Quarterly review for currency.