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Building Homes or Extensions/Anchoring metal framing posts to new concretencrdet

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Dan, I'm building a metal framed workshop 33X42ft. Not a kit. Looking for easiest way to anchor 4X4 posts.  Not confident I can precisely position bolts prior to pour.  On other hand I'm  skeptical of strength of post pour anchoring systems.  What alternatives could work - ie. welding rebar to flat metal plate before the slab pour (that I could latter weld the posts to; or cementing metal posts deeply cement prior to pouring slab (pole barn approach).  aNY THOUGHTS about easiest approach WOULD BE WONDERFULL!

Answer
David, interesting question.  How are you anchoring the bottom of the 4x4?  I'll assume you're using some type of hold down anchor such as
http://www.strongtie.com/products/connectors/AB-ABA-ABE-ABU.asp

There are some interesting anchors available such as:
http://www.powers.com/product_07246.php

http://www.powers.com/approvals.php#2526
ESR 2526 gives the technical data on pull out, edge distance, etc.

The best anchorage would be a properly installed J bolt.

Remember that you will need to have sufficient anchors to control uplift on the structure as well as downward forces involved.

I'm not sure that you can get the necessary anchorage, tension, and shear with a single anchor at the base of a 4x4.  A typical metal building would use steel columns with substantial base plates with 4 deeply imbedded j bolts.  The J bolts are installed deep enough to use the footing for uplift.  J bolts are sized for shear and tension and would be installed using a pattern to control the location, well fastened to the concrete forms prior to pouring.

Do you have a code authority that will be inspecting this?  You may require the services of a structural engineer to make an adequate structure.

I ran across this while looking for an example of a metal base plate:
http://technorati.com/lifestyle/diy/article/tips-on-building-a-metal-garage/



I hope this gets you started in the right direction.

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Dan Griffin

Expertise

I can answer almost all questions related to the total construction process. My expertise is in commercial construction, though I can field most any residential question. I have hands on experience in concrete, heavy equipment, masonry, all phases of carpentry, interior finishes, and I am fairly strong in mechanical and electrical.

Experience

I have over 20 years experience as a commercial carpenter and commercial construction superintendent. I have another 20 years experience in facility management for a major school district.

Organizations
My favorite hobby for he past 12 years has been singing bass in a The OkChorale men's barbershop chorus and the Mature Moments quartet.

Education/Credentials
I hold a Bachelor's degree in English and Math. I have completed many continuing education hours in the building trades. I hold a Master Carpenter card from the AGC, Associated General Contractors.

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