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largest timber column available from the mill?

largest timber column available from the mill?

largest timber column available from the mill?

(OP)
I am designing a 14" x 14", 25' unbraced southern pine timber column, and I am wondering if this is too big of a cross section (or length for that matter) to expect from the lumber supplier.

Any ideas on where to find this out?

Thanks.

RE: largest timber column available from the mill?

Ive seen a lot of architects use 4 column tied together with black steel sleeve.  I think that looks a lot better than 1 gigantic column.  Maybe you want to go that route.  The bigger it is, the price goes up almost exponentially (just a guess, but it will be super expensive).  My recent project the architect used (4)-10x10.

RE: largest timber column available from the mill?

I can't say I've ever seen one that size.  I've seen telephone poles called out on architectural plans before.  I showed them the numbers on the weight of the pole and talked them into a small WF column (W8x24 I believe), wrapped in rough sawn cedar for the rustic look.

RE: largest timber column available from the mill?

(OP)
well the column is actually wrapped in an architectural shell so the look is not really important because it's going to be concealed.

thanks

RE: largest timber column available from the mill?

If you use 4 smaller columns bundled together be sure to design them as 4 separate columns and not one large column as the interface between does not transfer longitudinal shear and they act independently of each other....unless you bolt or nail them together per NDS and use the reduction coefficient found in the appendix for built-up columns.

RE: largest timber column available from the mill?

Why not use a glulam column?  We had a building that had glulam columns supporting glulam girders.

RE: largest timber column available from the mill?

If it is going to be concealed, why not just use multi columns?  You are wasting your money trying to get a member that size.  Steel column is probably cheaper.  

RE: largest timber column available from the mill?

It is possible, but the bigger it is the more expensive it will be.

RE: largest timber column available from the mill?

(OP)
Thanks for all the ideas guys.

When you see all those old fashioned houses with big front porches that have like 25' tall decorative columns...what is inside these column shells?  Surely it's not concrete.  

Big old square or circular timbers, right?

RE: largest timber column available from the mill?

My last project that had something simmilar they had a circular big column.  I was going to put a round tube steel but the architect told me to put a square one instead.  I think they will block it out to whatever shape  and put wires around and stucco it.  

RE: largest timber column available from the mill?

(OP)
but surely in the old houses they didn't use steel...big timbers i'd guess, right?

RE: largest timber column available from the mill?

I had a 24" diameter white fir log, 100+ feet long, in my yard up to a week ago.  Couldn't find anybody who wanted it.  Sigh.

RE: largest timber column available from the mill?

Yes old houses did use large timber, but in times past large timber was probably easier to obtain.
Depending on your location large timber is still available as a special order and at a price premium.
However, if it's not visible use steel, it should be cheaper.

RE: largest timber column available from the mill?

Trees are not left to grow long enough to get that big. Like us, trees grow faster when they are young, so if you leave it to grow for twice as long you dont get twice as much timber. More productive to have 2 growth cycles half as long.

Architects always seem to find huge timbers when they want them for architectural purposes, but they tend to be too expensive for structural use.

RE: largest timber column available from the mill?

Is there a Structural reason for such a big cross section? If not, then why don't you do a steel, or even wood column that has a section for what is needed. If a chubbier look is desired you can always clad it with some sort of wood finish.

My 2 cents.

p.s.
A few years ago I investigated a 12"x12" heavy timber column and found its capacity close to 90 kips for the given case.

RE: largest timber column available from the mill?

You may not find it locally. Specialty saw mills (usually small companies) can supply that size and larger. Here in the North West there are a few mills that can supply larger and longer fir beams. Idaho and eastern Oregon have many large pine trees.

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