old southern pine density? 2

[SLTA]

Anybody know what the DL psf of southern pine from the 1920s was, or the density? I have worn out the phone and google... I have to be as accurate as possible on the weight for a remodel.

3/4" diagonal pine sheathing on a house from the 1920s, in Western North Carolina.

cheers!

 

[msquared48]

My 1966 AITC shows 5 psf for 2" nominal Southern Pine. So, using my trusty HP calculator, that yields 1.875 psf DL.

Mike McCann
MMC Engineering

 

[SLTA]

Sorry, I don't trust HP calculators

I actually just found the answer in an old 1899 "Building Trades Pocketbook". 4 psf/inch!

 

[msquared48]

Well, my 1958 Douglas-Fir Use Book shows Pine, Longleaf, Southern at 55 pcf unseasoned, and 42 pcf seasoned.

AGAIN, using my very, very trusty HP calculator, that translates to 3.44 and 2.63 psf respectively for 3/4" material. Might check and see if that 4 psf value/in. is a seasoned value or not. Could be a little high.

On considering the long range implications of these calculations, does this mean that old southerners are dense?

Mike McCann
MMC Engineering

 

[SLTA]

Good thing I'm not old!

 

[boo1]

3.75 psf
HP calculator - 15c used since college in the mid 1980

 

[msquared48]

There is this business too. They could have some better info...

http://pioneermillworks.com/get-to-know-us/unearth-the-story

Mike McCann
MMC Engineering

 

[boo1]

http://www.hearnehardwoods.com/hard...c_wood/heart_pine_lumber/heart_pine_wood.html

 

[SlideRuleEra]

SLTA - Per the "1923 Carnegie Pocket Companion", Page 300:

Long Leaf Yellow Pine: 44 Lb/Ft^3
Short Leaf Yellow Pine: 38 Lb/Ft^3

Both were, and are, considered to be "Southern Pine".

If you need printed documentation, you can download the book from this page of my website:

http://www.slideruleera.net/miscellaneous.html

Both the 1917 and 1934 Editions of the Carnegie Pocket Companion also list the same values. So, that pretty well covers the 1920's.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[Hokie93]

The first edition AISC Steel manual provides the exact same densities as quoted by SlideRuleEra. The information is on page 178 in my 1932 (tenth printing) copy.

 

[racookpe1978]

found the answer in an old 1899 "Building Trades Pocketbook". 4 psf/inch!

But, is that calc for today's "skinny" cuts of wood, or for the "original" defintion of 2x4 and 3/4 thick boards or for the roguh cut old-old wood?

 

[Ron]

slta...almost as dense as a contractor

 

[msquared48]

Hey Ron... Better qualify that last statemment. A lot of us here do independent contracting.

Mike McCann
MMC Engineering

 

[msquared48]

Hey Ron...

Better qualify that last statement. A lot of us here are independent contractors...

Mike McCann
MMC Engineering

 

[hokie66]

But then a lot of us here are dense...

 

[msquared48]

Very true Hokie... Just like old growth timber. Much better than today's.

Mike McCann
MMC Engineering

 

[Ron]

Mike...Contractor in the sense of those who build things incorrectly that we design!....or more likely, those who build things without bothering to look at the design (as in plans and specs).

hokie66....I'm a lot more dense than Southern Pine. I'd be classified as hardwood....and not necessarily in a good way.

 

[XR250]

@SLTA;

Just curious on how you would have to be that accurate where +/-1 PSF of DL on the floors or walls would make that much difference?

 

[Ron]

ExcelEngineering.....simply to answer the question that the attempt was made to be as accurate in all aspects of the evaluation as practicable. It's called "liability"!

 

[SLTA]

In this case, the size of what I'm supporting above would mean the difference between steel or engineered lumber, if I'm too heavy, and unacceptable deflections if I'm too light. Plus what Ron said.