How Much Will A 2x4 Roof Joist Support

Assuming the fb of hemfir is maxxed at 1275 psi and i came up with 12 737 psf.

How much will a 2x4 roof joist support.

How much weight can a 2x4 ceiling 16 on center hold. That a 4x8 sheet of 3 4 plywood with 2x6 joist on the edge and 2x4 joist in the middle can support. But if you ask engineers what they do in their own garages you ll get a different answer. An syp rafter can span 8.

You are correct in that a 1x would not provide much support for your roof s ridge line. They re designed to support your roof not your junk. Would 2x4s be adequate ceiling joists for ceilings with drywall and insulation. Here you can operate by assumptions that there is no wind or it is not as strong.

If this is the case with your structure use the floor joist table to determine maximum joist length load. I used your formula backwards to calculate the max psf of a ceiling with 2x4 ceiling joists spanning 12 and spaced 24 o c. However if there is no strong wind measure 2 4 at least 8 feet can carry at least 1000 pounds vertically. Span calculator for wood joists and rafters also available for the android os.

Joist span tables use these tables to determine lengths sizes and spacing of ceiling joists. The fact that your ceiling joists span 15 feet and are only 2x4s and are holding up plaster and lath it makes more sense that the 1xs were trying to support the ceiling joists below. Here you can work on the assumption that there is no wind or the wind impact effect is not too strong. Each ceiling joist is one 12 foot 2x4 turned on end and total answered by a verified structural engineer.

How much weight can a 2 4 support vertically. That seems like it would support a lot of dead load. Such calculations would be valid if for example the load is quadratic. But i doubt this was the intention.

Also available for the android os. It will make less sense to use 2 4. If the bottom chord of a roof truss functions as a floor joist such as in an attic room it carries a live load that also varies by use but a typical live floor load for a residential space is about 40 pounds per square foot. So if your ceiling is unfinished you have some excess carrying.

However it is highly advisable not to push the 2x4 material up to its limit. Such calculations would hold if for instance the load is square. If there is no strong wind a 2x4 measuring at least 8 feet can support at least 1 000 pounds vertically. While the heavy load span specs for a 2 4 rafter are much less than a light load they would allow you to have a shed width of over 14 with a gable roof.