Tuesday, September 20, 2011

Allowable Stresses in Dimensional Lumber

Joists: Floor and Roof 2'' x 8''

Species: D, F South
Grade: No 1
E: 1,300,000 psi

F'b (Floor) = Fb x Cf x Cr x Cfu = 1277 psi
F'b (Roof) = Fb x Cf x Cr x Cfu = 1064 psi
F'v = Fv = 180

Beams: 4'' x 8''

Species: D, F South
Grade: S, S
E: 1,400,000

F'b = Fb x Cf x Cfu = 1843 psi
F'v = Fv = 180

Headers: 2'' x10''


Species: D, F South
Grade: No 1
E : 1,300,000 psi

F'b = Fb x Cf x Cfu = 1221 psi
F'v = Fv = 180

Studs: 2'' x 6''

Species: D, F South
Grade: Stud
E : 1,100,000 psi

F'b = Fb x Cf x Cr = 1009 psi
F'c = Fc = 830 psi

Posts - Columns: 4'' x 4''

Species: D, F South
Grade: No 1
E : 1,300,000 psi

F'b = Fb x Cf = 925 psi
F'c = Fc = 1450 psi

Tuesday, September 13, 2011

Dead Loads




Dead Load Calculations:



Exterior Wall and Window Wall Weight:                 11 psf                                                    43,072 lbs.

Interior Wall Weight:                                                   4.5 psf                                                   4,343 lbs.

Wood Floors:                                                                 8.6 psf                                                   24,080 lbs.

Roof:                                                                               10.1 psf                                                  25,250 lbs.

Wood Beams:                                                                5 lbs./ lin. ft.                                         2,078 lbs.

Wood Columns:                                                             5 lbs./ lin. ft.                                         630 lbs.

Steel Columns (2.5" round steel pipe):                      8 lbs./ lin. ft.                                         504 lbs.

Concrete Floor 6" thick (Basement):                          75 psf                                                     137,328 lbs.

Foundation Walls 8" thick:                                           60 lbs./ lin. ft.                                       14,139 lbs.

Column Footings 8" thick:                                            100 lbs./ lin. ft.                                     2,800 lbs.

Wall Footings 8" thick:                                                  100 lbs./ lin. ft.                                     23,565 lbs.

 ____________________________________________________________________________________

Weight Above Ground:                                                                                                                 99,453 lbs.

Weight Below Ground:                                                                                                                 178,336 lbs.

Total Weight of Building:                                                                                                              277,789 lbs.

Square Footage Above Ground (including Roof):                                                                    5,300 sq. ft.


Average Dead Load Above Ground:                             99453 lbs./ 5300 sq. ft.=                 18.8 psf