Engineered Floor Joist

During the process of adding the spiral stair's and making the enclosure to bring it to the inside of the house, I decided to extend the second floor in order to keep the addition from looking like a shaft on the side of the house, in addition to adding much needed floor space. I had plenty of 2X4 stud's, but lacked the floor joist, which I decided that 2 X 6 would work due to the fact that the addition was less than 8'. In the original part of the addition, the 2 X 6's worked fine in terms of strength. There was a small bit of spring, but they were plenty strong for the task at hand. One thing I didn't like was that the material delivered was not of uniform quality or measure (width).

The money for more 2 X 6's simply wasn't there and after kicking around a bit, decided that the project would need to be put on hold until more material could be purchased. I went inside and turned on "DIY Network", and more specifically, "This Old House" with Norm and happened to catch an episode where they were putting down floor joist in a second floor addition. The joist's they were using were engineered and they couldn't say enough about them. They were basically an OSB (orientated strand board/wafer/chip-board) spline with a 2 X 2 dadoed and glued on each side. This I could do! I had plenty of 7/16" OSB, some liquid nail, and the time.

After a couple of hours I had produced what I needed and was quite happy with the results. While the standard material was somewhat sufficient, these jewels were rock solid, exact in measurement, not too hard to make and are quite economical.

The standard 2 X 6 ran me around $6.00. The material for the homemade engineered joist worked out to be quite a bit of savings.

2 X 4 = $ 2.00

OSB spline = $ 0.50 -->I ripped 12 spline's from a standard of 7/16" 4 X 8 OSB at a cost of $5.00 per sheet....$0.46 per spline

Liquid Nail = $ 0.50 --> one tube @ $2.50 each makes five joist's.

1 joist = $3.00

Savings = $3.00

I can make eight joists in an hour (now that I have the technique down) which means I earned/saved $24.00 in that same hour over using standard board stock.

While I'm not advocating that anyone use this technique without the use of an engineer, I present how I managed it.