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What is a fire cut floor joist?

Building Supplies
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Manage My Life
A fire cut joist is a regular floor joist, except for the end where the end of the joist rests on a supporting wall. A regular joist has a square cut end, whereas a fire cut has an angled cut on the end. The angled cut is made towards the top middle of the joist, from vertical. This is done so that if a fire in a building causes the floor to collapse, the floor will fall out of the wall easily. If the joist has a regular square cut end, as the floor collapsed, the end of the joist can push up on the wall above it, causing that wall to tip over.

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by Manage My Life
December 7th, 2008
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