{"id":17678,"date":"2026-11-07T20:15:30","date_gmt":"2026-11-07T19:15:30","guid":{"rendered":"https:\/\/ventsystems.de\/kippfenster-dreifachglas-250-n-antrieb\/"},"modified":"2026-11-08T08:15:10","modified_gmt":"2026-11-08T07:15:10","slug":"bottom-hung-window-triple-glazing-250-n-actuator","status":"publish","type":"post","link":"https:\/\/ventsystems.de\/en\/kippfenster-dreifachglas-250-n-antrieb\/","title":{"rendered":"Bottom-hung window with triple glazing: is a 250 N actuator enough?"},"content":{"rendered":"

In brief:<\/strong> Yes, in most cases. A bottom-hung window measuring 1.2 \u00d7 1.0 m with triple glazing weighs around 40 kg, but at 300 mm stroke needs only about 63 N, around 80 N with 30 % reserve. A VS-KA<\/a> with 250 N therefore has more than enough force. Limits are set rather by the sash width (two actuators from 1.5 m) and the tilt hardware.<\/p>\n\n\n

Why does a bottom-hung window need so little force?<\/h2>\n\n\n

On a bottom-hung window the hinges are at the bottom. The sash tilts inwards only a little, and the hardware carries most of the weight. The actuator at the top edge only has to push the sash out of the vertical. The usual approximation is F = 0.54 \u00d7 m \u00d7 g \u00d7 stroke \/ sash height \u2013 the smaller the stroke relative to the sash height, the less force.<\/p>\n\n\n

Worked examples with triple glazing 4-14-4-14-4<\/h2>\n\n\n
sash<\/th>Weight<\/th>Stroke<\/th>Force<\/th>with 30 % reserve<\/th><\/tr><\/thead>
1,2 \u00d7 1,0 m<\/td>approx. 40 kg<\/td>300 mm<\/td>ca. 63 N<\/td>approx. 80 N<\/td><\/tr>
1,2 \u00d7 1,0 m<\/td>approx. 40 kg<\/td>150 mm<\/td>ca. 31 N<\/td>ca. 40 N<\/td><\/tr>
1,4 \u00d7 1,4 m<\/td>ca. 65 kg<\/td>200 mm<\/td>ca. 49 N<\/td>approx. 65 N<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n

Weight estimated with 30 kg\/m\u00b2 glass plus 10 % frame, see Glazing build-up<\/a>. For heavy aluminium or timber frames, better use the real weight.<\/p>\n\n\n

What really matters<\/h2>\n\n\n