Should We Upgrade Floor Joists

Follow the rules to keep your floor solid.

Should we upgrade floor joists.

If they re really only 6 long 2x6 s at 16 on center are fine in fact they ll go a bit further under normal conditions. While you may be ok with the joist span at 24 inches the floor will be maxed out to the limits. To avoid buckling subfloor panels should be spaced with a 1 8 inch gap at all edges and ends to provide room for naturally occurring expansion. The three main types of floor joists used in home construction are solid lumber i joists and open web floor trusses.

See the image below for an example of joists spaced 16 on center 16 o c. Common sense tells you that large floor joists can carry more load and spacing joists closer together also increases the load bearing capacity of a floor. You can notch and bore joists without sacrificing critical strength but you must follow the rules. The notching and boring rules of thumb for solid lumber are shown in fig.

Joist span and spacing is set by your local building code. You say the span of the joists is probably 6 feet but that the critical measurement. Each type of floor joist offers its own unique benefits and drawbacks which is why those working in carpentry all tend to have their own favorite floor joist option though they are still required to be well versed in each type of floor framing. Tongue and groove edges on many premium floor panels such as weyerhaeuser s edge gold osb panels are designed to self gap.

Sistering installing new larger joists next to the existing ones is one way to bring your attic floor up to code. Since the example house we are designing for is 12 feet wide we need to find in the floor joist span table a joist size and centering that can span 12 or wider. But larger is not always better when builders are constructing a home or adding a room addition. Spacing joists in your shed 16 inches on center will give you a firmer feel with less bounce and increase the load capacity of the floor.

While most residential construction uses 2x8 joists with 16 inch spacing there are many other factors you need to consider when determining the proper joist span length. In the past 2x4s or 2x6s were sometimes used as floor joists. Floor joists installed on second or third or higher levels double as ceiling joists for the level below. In buildings with basements the first level of floor joists serves the same purpose.

The floor joist spacing is the distance between the centers of any two installed joists. If they are older dimensional lumber back when a 2x6 was actually 2 by 6 they ll go even further. Positioning the new joist adjacent to the existing preserves precious ceiling but it does come with some potential complications.