Top-Hung Window

The Window That Stays Open in the Rain

A top-hung window — the same thing as an awning or projected window — is hinged along its head and opens outward at the bottom. The open sash forms a small canopy over its own opening.

That single property is the reason to specify one. It can be left open during rain without water coming in, which no other outward-opening type can do. In a bathroom, a utility room, a kitchen or any space that needs continuous background ventilation, that is worth more than a larger opening.

How It Seals

Like a casement, it closes by compression — the stay or operator draws the sash onto a gasket all round. It performs well on air infiltration, close behind casement and tilt-and-turn and comfortably ahead of any sliding type.

It also suits openings that are wider than they are tall, which is the shape a casement handles worst. A wide casement is a long lever on its hinges; a wide top-hung sash is supported along its whole head.

The Limitation That Decides Most Specifications

The opening angle is limited — by the stay, by the projection into whatever is outside, and by the geometry. The clear opening is therefore smaller than a casement of the same size.

That usually rules a top-hung window out as a required means of escape, and it reduces how much ventilation it delivers for its area. Where an opening has to satisfy an egress requirement, this is the wrong window type and it needs checking before ordering rather than after.

Reach and Operation

Top-hung windows are frequently placed high — above a door, high on a bathroom wall, in a stairwell — which is precisely where nobody can reach the handle.

A chain operator or a pole-operated stay handles moderate heights. Above that, an electric operator is the practical answer, and on a stairwell or an atrium it is usually the only one. Electric operation also allows the window to be tied into a ventilation or smoke control system where that is required.

Combinations

The common and sensible arrangement is a large fixed lite with a top-hung vent below or above it. The fixed portion gives the glass area and the sightlines; the vent gives ventilation that can be left open in weather, and you only pay for hardware where it does something.

Where Top-Hung Windows Fit

These describe the kind of work each area brings rather than any specific client project.

Bathrooms and utility rooms — citywide. Small, high, able to stay open in rain, usually with obscure glass. The most common residential application.

High-level and transom vents — townhouses, loft conversions, stairwells. Above doors and in double-height space, with chain or electric operation because nothing else is reachable.

Commercial and institutional — schools, offices, healthcare. Robust, simple, weather-tolerant, and easy to restrict where public access requires it. Frequently specified as a ventilation band above fixed glazing.

Exposed and coastal — the Rockaways, Staten Island's South Shore, the Shore. Outward opening means wind pressure pushes the sash onto its seals rather than away from them, which works in your favour — but the stay has to be rated for the exposure or a gust will find the weakness.

Tell us the opening dimensions, the height above floor level and whether the opening has to serve as an escape route. We supply and install across Manhattan, Brooklyn, Queens, the Bronx and Staten Island, and throughout Northern New Jersey, the Jersey Shore, Philadelphia and the Lehigh Valley.