2019-05-10

## What size timber should I use for floor joists?

Solid strutting should be at least 38 mm thick timber extending to at least three quarters the joist depth e.g. 200 x 50mm joists would need at least 150 x 38mm timber used as strutting.

## What is the standard floor joist size?

Typical Floor Joist Size In Residential Construction Floor joists range from 2×8 to 2×12. It is less common to see joists that are 2×6, even though they are included in joist span tables. Older homes are more likely to use 2×6 for joist framing.

How far can a 2X8 ceiling joist span without support?

A rule of thumb is 1.5 times a joist’s depth but in feet when spaced at 16” centers. In general, a 2×8 will span 1.5 x 8, so 12-feet.

### What is the spacing between floor joists?

The spacing of floor joists is just one of the components used to determine the minimum size of the floor joist. Per the prescriptive tables found in Chapter 5 of the International Residential Code (IRC), the standard floor joist spacing used is 12, 16, 19.2, and 24 inches on center.

### How big of a joist do I need for an 8 foot deck?

So, for an 8 foot long (2.44 m) deck, a Redwood joist of grade 2 lumber would need to be 2 x 6 (50.8 x 152.4 mm). A larger joist size would be perfectly acceptable, whereas a smaller size would not. The 2 x 6 joist size is suitable for most types of grade 2 lumber at 8 feet (2.44 m) in length. Is Amazon actually giving you the best price?

How to calculate the length of a floor joist?

Floor Joist Span Calculator. To use the joist span calculator below, first select the species of lumber you will use for your construction project from the drop-down list. Next use the buttons in the table to select the maximum length in feet (or metres in brackets) that your floor joists must span.

## How big is 2 in x 8 lumber?

A well-known size by pros and DIYers alike is 2 x 4 lumber. Other common sizes include 1 x 4 lumber, 1 x 6 lumber, 2 x 2 lumber, 2 x 6 lumber, 2 x 8 lumber and 2 x 12 lumber. These measurements are the depth and width of the board.

## How big should a ceiling joist and Rafter be?

Species Alaska Cedar Alaska Hemlock Alaska Spruc Size 2×4 2×6 2×8 2×10 2×12 Grade Select Structural No. 1 No. 2 No. 3 Stud Member Type Floor Joists Ceiling Joists Rafters (Sno Deflection Limit L/720 L/600 L/480 L/360 L/240 L/180