In article , Dave West
wrote:
Someone with a basement flat with old wooden frame vertical sliding sash
windows wants some simple to fit security device to enable the window to
be left open safely a couple of inches whilst no one is in the flat.

Grateful for an suggestions on a simple to fit device.

my parents' home had what was referred to as a "Burglar catch". This was a
dropdown bar recessed into the upper sash when not set. This dropped down
with a gravity locking mechanism and prevented the lower sash opening more
than a preset amount. I've also come across a tapped plate, againe
recessed into the upper sash, into which you could screw a peg to prevent
the lower sash getting past. the first is neater and has no parts to get
lost. I'm sure any good architectural ironmonger will stock them.

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From KT24

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