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It is a very common and at the same time unpleasant phenomenon, for buyers of aluminum frames, to realize after the installation of the frames one of the following:
- The opening they saw before, suddenly became much smaller
- The light that passes is low
- In the end, the type of frame they chose or suggested was not suitable for the specific location
This is because the frame consumes a lot of space from the original wall opening and from the interior and exterior space. In this article we will not consider the specifications of the frames in terms of their wind and thermal permeability. We will only look at the space they occupy and will refer to three main categories of frames:
Hinged, Sliding Overlapping and Sliding Recessed.
The numbers listed below are indicative, as they vary depending on the extrusion companies (system producer) and the series of frames.
A. Hinged
The hinged frames are the ones that consume a lot of space, because during the operation of the movable frames (opening-closing door or window) they have a curved path inwards for the glazing or outwards for the shutter (if there is one). If, for example, an object is to be placed in front of them (e.g. table, sofa), they are not suitable and it is advisable to choose another solution. These frames are mainly installed in detached houses, special buildings and also for the replacement of old, usually wooden frames.
The calculations for the application of the above, when e.g. we have an initial masonry opening of 100cm width and 220cm height, including the false ceiling, are as follows:
- Main entrance door without threshold
Net width opening 100cm – 18cm = 82cm
Net opening height 220cm – 9cm = 211cm - Single-leaf openable with threshold
Net width opening 100cm – 19cm = 81cm
Net opening height 220cm – 19cm = 201cm
Visible glass width 100cm – 29cm = 71cm
Visible glass height 220cm – 29cm = 191cm - Double leaf opening with threshold
Net width opening 100cm – 19cm = 81cm
Net opening height 220cm – 19cm = 201cm
Visible glass width 100cm /2- 23cm = 27cm
Visible glass height 220cm – 29cm = 191cm
B. Sliding overlapping
Overlapping frames are those that do not consume any of the usable space – inside or outside – because the frames move along their horizontal axis. They are suitable for large openings because they can use more than 2 frames (3,4,5,6). Of course, they will not give us the maximum opening of the masonry because when the movable frames move (e.g. in a two-leaf overlapping), one leaf covers the other.
The calculations you can make for an initial masonry opening e.g. 150cm wide and 220cm high including the false ceiling are as follows:
- Double leaf overlapping
Net width opening 200cm / 2 – 20cm = 80cm
Net opening height 220cm – 16cm = 204cm
Visible glass width 200cm / 2 – 19cm = 81cm
Visible glass height 220cm – 30cm = 190cm
C. Sliding recessed
Sliding recessed units, like sliding overlapping units, do not take up any of the useful space – inside or outside – because the frames move along their horizontal axis. In this type of frame, two separate walls are required, with the frame guide between them. This implies a considerably thicker masonry opening. They are divided into two categories: single-leaf and double-leaf.
The calculations you can make for an initial masonry opening e.g. 150cm wide and 220cm high including the false ceiling are as follows:
- Single leaf recessed
Net width opening 150cm – 22cm = 128cm
Net opening height 220cm – 16cm = 204cm
Visible glass width 150cm – 26cm = 124cm
Visible glass height 220cm – 30cm = 190cm