Framing Your House (cont. p. 11)

The I–Joist

The I-Joist is an engineered wood product that comes in multiple lengths and heights.  It has advantages over 2x boards, but is more costly. 

 

 

 

Because I-Joists are manufactured, not sawed from a raw tree trunk, they are never warped or crowned.

Relative to weight, they have greater load-bearing capacity than a 2x.

In some cases, it is possible to use fewer of them, offsetting the higher per cost per unit.

The top section of the I-Joist can be 2 ½ to 3 ½ inches wide, providing a superior nailing and gluing surface.

This makes floor squeaks far less likely to occur.

Some I-Joists feature pre-cut openings to accommodate plumbing, wiring, and duct work.



Your lumber representative will have span tables which indicate requirements of joist size and spacing.  A cost comparison versus 2x boards is then easy to figure.
   

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