Loft Floor Joist 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.

Loft floor joist calculator. This is the distance between joist centres. The new floor joists of your loft conversion will need to offer at least 30 minutes worth of fire protection which could mean replastering the ceilings in those first floor rooms below. Calculations to bs 5268 2 2002. In the example the joists have a spacing of 16 inches and a span of 11 feet 2 inches.

Domestic floor joist calculator. Span calculator for wood joists and rafters also available for the android os. Most lay outs are on 16 so the field is pre selected. The span table for a 30 psf live load 10psf dead load floor indicates a required fb value of 1 315 and a minimum e value of 1 800 000.

Next use the buttons in the table to select the maximum length in feet or metres in brackets that your floor joists must span. This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction. True floor joist span calculations can only be made by a structural engineer or contractor. It has been my experience to never use a beam smaller than a two ply 2 x 8.

The highest is a fully loaded floor 70 pounds per square foot. Floor joist span calculator. 1 enter joist details 1 1 span and joist spacing. This calculator matches up with 90 of the applications in the 2012 international residential code book.

Usually 400 450 or 600mm but any value can be used up to 610mm max. The lowest is a plain ceiling joist with no storage 10 pounds per square foot. The full version allows any size. There are six choices.

This is how far apart they will be. Also available for the android os. No matter what the specs say. In this case your joists are adequate to support a 30 psf live load and 10 psf dead load.

This demo version is fixed at 1m clear span. Timber loft floor joist calculations trimming joists. Select the on center spacing for the joists.