2x8 Floor Joist Load Capacity

Yellow Pine Douglas Fir. A live load of 60 pounds per square foot demands more support and shorter spans.

How To Size Floor Joists Per The Irc Easily Explained With Examples Building Code Trainer

The house is a 40 yo bungalow.

2x8 floor joist load capacity. A uniform load rating on a beam can easily be translated into what an equivalent maximum point load can be. For example in the joist span table below the highlighted cell shows that 2 x 8 Southern Yellow Pine joists that have a grade of 2 and are spaced 24 apart can have a maximum span of 10 feet - 3 inches 10-3 if designing for a live load of 40 lbsft 2. Works out to 1314 for a 2X8.

E values are unaffected by duration of load. Maximum Span Calculator for Joists Rafters. Based on all factors though a 28 joist span is 7-1 to 16-6 and a rafter 6-7 and 23-9.

Maximum floor joist span for No. While the same grade and species 28 has a 3040 Fb when used as a roof rafter in snow country. 2x10 to 15 feet and 2x12 to 18 feet.

Floor joist capacities for timber grade C 18 C 24 and C 30 - joist center space ranging 300 to 600 mm - are indicated in the diagram below. With an evenly distributed live load of 30 psf which the tables show the floor is able to support the total weight on the floor would be about 3360 pounds. In general terms joists spaced 16 inches on center can span 15 times in feet their depth in inches.

If we assume the bending value for your 2X8s is about 1200 SYP 2 we would have a moment capacity of 1314 foot pounds. Bending Strength F b How to calculate load capacity on construction. Our joist span charts are for wood joists with a maximum dead load of 10 pounds per square foot and a live load of 40 pounds per square foot.

Structural capacity of 2x8 floor joists. 2 Jun 28 2007. 1 in 254 mm.

Second the Dead Load is probably about 25 psf for gypsum board ceiling plus 2 psf for the 2x8 joists at 16 on center plus 3 psf for plywood subfloor and plywood underlayment plus 25 psf for carpet or wood flooring for a total Dead Load of 10 psf. My current project involves enlarging a bathroom and moving a bathtub. The strength classes C 16 C 24 and C 30 referes to Eurocode 5 and BS 5268.

A rule of thumb is 15 times a joists depth but in feet when spaced at 16 centers. Alaska Cedar Alaska Hemlock Alaska Spruce Alaska Yellow Cedar Aspen Baldcypress Beech-Birch-Hickory Coast Sitka Spruce Cottonwood Douglas Fir-Larch Douglas Fir-Larch North Douglas Fir-South Eastern Hemlock-Balsam Fir Eastern Hemlock-Tamarack Eastern Softwoods Eastern White Pine Hem-Fir. Google span calculators to give you a better idea.

Location and configuration of heavy loads should be looked at on a case by case basis. In general a 28 will span 15 x 8 so 12-feet. Span is determined by species grade dimensions spacing use and load.

A select structural southern pine 28 floor joist has a 2650 Fb. Most floor loads would be a minimum of 2x8 16 oc and most preferbaly 2x10. The information included in these charts is derived from the International Residential Code 2012.

1 ft 03048 m. A 2x8 up to 12 feet. Section modulus X bending value for the lumber divided by 12.

Live load is weight of furniture wind snow and more. A 20 2x8 will not carry very much load at all. Dead load weight of structure and fixed loads 10 lbsft 2.

So your 2X8s arent even close at 16 OC. Live Load 30 lbsft 2 1436 Nm 2. 2x8 are not used for floor systems.

Floor joist capacity - max working load 20 kNm 2 - as pdf file. Spaced at 12 inches the joist may only span 16 feet 8 inches. 40 psf Live Load 3 10 psf Dead Load L480 30 psf Live Load 10 psf Dead Load L360.

Live Load psf Dead Load psf Span Calculator for Wood Joists and Rafters available. You will probably need a beam running perpendicular to the 20 2x8 somewhere in the middle to seperate the span to 2 10 spans to be able to use the space above. While the same grade and species 2x8 has a 3040 Fb when used as a roof rafter in snow country.

At 16 inch spacing 15 feet 2 inches and 13 feet 3 inches at 24 inch spacing. A select structural southern pine 2x8 floor joist has a 2650 Fb. Floor Joist Span Table.

Modulus of Elasticity E 1400000 psi. Increasing the total weight on the floor to 4480 pounds however results in a live load of 40 psf which is beyond the floors load capacity. This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on-center oc 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.

How long can floor joists be without support. Then the moment capacity can be figured with this formula. 1 psf lb f ft 2 4788 Nm 2.

The proposed 1000 lb or so live load 500lb stone and 500lb stove divided over the area of 25 sq ft brings a total of 40lbs per sf live load over the area or LESS than a standard 2x10 16 inch on. A live load of 60 pounds per square foot demands more support and shorter spans. For example a floor joist at 16 spacings that can carry 53 pounds per linear foot would translate into a 318 pound single point load at its center.

2 Grade of Douglas fir are indicated below. Floor Joist Capacity - max working load 20 kNm2. I will attempt to clearly describe my situation.

How long can floor joists be without support. You should check with your local building department for construction requirements in your area. The main floor is supported by full dimensional 2x8s 16 oc floor joists covering a span of 12.

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