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(civil engineering)
A steel or wood beam providing direct support for a floor.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


One of a series of parallel timber beams used to support floor and ceiling loads, and supported in turn by larger beams, girders, or bearing walls; the widest dimension is placed in the vertical plane.

ceiling joist

Any joist which carries a ceiling; one of several small beams to which the ceiling of a room is attached. They are mortised into the sides of the main beams or suspended from them by strap hangers.

floor joist

Any joist or series of joists which supports a floor.

solid-web joist

A conventional joist with a solid web formed by a plate or rolled section, as opposed to an open-web joist.

trimming joist

A joist supporting one end of a header at the edge of an opening in a floor or roof frame, parallel to the other common joists.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved


joists in a flooring system
One of a series of parallel beams of timber, reinforced concrete, or steel used to support floor and ceiling loads, and supported in turn by larger beams, girders, or bearing walls; the widest dimension is vertically oriented. Also see binding joist, boarding joist, bridging joist, ceiling joist, common joist, floor joist, principal joist, sleeper joist.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
References in periodicals archive ?
9 January 2018 - Connecticut, US-based alternative asset management firm Black Diamond Capital Management, LLC has closed on the acquisition of Alabama, US-based joist and deck manufacturer Valley Joist from Alabama-based conglomerate EBSCO Industries, Inc., the company said.
("Black Diamond") has announced that it has acquired Valley Joist from EBSCO Industries, Inc.
Nucor Corporation (NYSE: NUE), a manufacturer of steel products, with operating facilities primarily in the United States and Canada, has acquired the assets of Omega Joist, a subsidiary of Samuel, Son & Co., Limited.
The simulated joist is part of a one-way slab of 30 cm thickness with a span of 4.92 m between column axes, with flat beams of 60 cm width.
Hold a straightedge across joists to make sure they form a flat surface for the ceiling.
Simply screw the Loft Legs to your existing joists. Its best done using Wickes Ultra Gold Screws 4.0x30mm which are PS12.88 for a pack of PS1,000.
Our contractor, instead of removing the breast up to the top, had left it in place in the loft and propped up its outer edge with a length of wood which was in turn resting on the ceiling joists.
It is a high-performance fastener that allows architects and builders to provide their clients with clean, uniform and long lasting metal joist decks - something that was previously not possible without considerable time and effort.
"We are delighted that our partner, Innovative Engineering, has been recognized as a Design Award Winner by the Steel Joist Institute," said Wayne Pfisterer, president of Pfister Energy.
It is very rare for the boards to meet naturally on a joist. Normally, a board has to be cut so it finishes in the middle of the joist.
There are several causes of this, but one of the most common is the nails that fix the floorboards to the joists becoming loose over time.