http://www.homebuildingandrepairs.com... Click on this link for more information about floor framing, new home construction and building repairs. Here's another video that might be helpful for anyone planning on building a home with manufactured 2 x 4 floor joist, especially if you're going to be installing a stairwell for a set of stairs. Keep in mind that most 2 x 4 engineered floor joists systems are designed specifically for each project and parts might not be interchangeable or able to be cut or modified in any way for smaller spans.