# What Is a Condensation Channel?
**A condensation channel, also called a condensation profile, is a specially designed groove or profile integrated into window frames to collect and drain away condensation water. It prevents moisture from accumulating on the frame or sill and causing damage to the surrounding structure.**
## How it works
When warm indoor air meets the cold glass surface of a window, condensation forms and runs down to the bottom of the glazing unit. The condensation channel catches this water before it can reach the frame joints or interior sill. Small drainage holes (weep holes) at the base of the channel allow the collected water to exit to the outside of the building.
## Where condensation channels are used
– **Aluminium window frames** — Most commonly found in aluminium systems, where thermal bridging makes condensation more likely.
– **PVC window frames** — Modern PVC profiles often incorporate condensation channels as standard.
– **Timber-aluminium combinations** — Hybrid frames use channels on the aluminium exterior side.
– **Curtain wall systems** — Large commercial glazing systems rely on condensation channels to manage moisture across extensive glass surfaces.
## Design considerations
– The channel must be wide and deep enough to handle peak condensation loads during cold weather.
– Drainage holes should be positioned to allow gravity-fed outflow and must be kept clear of debris.
– Proper sealing between the channel and the glazing unit prevents water bypass.
– In high-humidity environments such as swimming pools or commercial kitchens, oversized channels may be specified.
## Maintenance
Regular inspection of drainage holes is important. Blocked weep holes can cause water to back up and overflow into the interior, leading to water damage and mold. Cleaning with a thin wire or compressed air keeps the system functioning properly.
## Related terms
– Weep hole
– Thermal bridge
– Glazing bead
– Window sill
– Condensation
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