Porch Columns

[globe trekker]

I have an existing house that wants to add a patio area and build a "new"

roof over it. The "new" roof will be approx. 24 ft. long by 19 ft. wide.

The plans indicate 4 - separate 4" x 4" wood columns to be installed for

support of the span.

QUESTION: Is there somewhere in the IRC that requires anchorage

to the foundation ( i.e. - some type of anchorage device / components )

if there is no clear indication that the vertical columns / posts will be

installed sub-grade? I'm looking for a code section to refer the builder to!

Thanks for any input!

.

 

[SCBO1]

Globe,

Try, IBC 2006 sec. 2304.9.7, columns to resist uplift.

 

[TimNY]

R802.11 Roof tie-down.

"A continuous load path shall be designed to transmit the uplift forces from the rafter... to the foundation"

 

[permitguy]

R407.3 Structural requirements. The columns shall be restrained to prevent lateral displacement at the bottom end. Wood columns shall not be less in nominal size than 4 inches by 4 inches (102 mm by 102 mm). Steel columns shall not be less than 3-inch-diameter (76 mm) Schedule 40 pipe manufactured in accordance with ASTM A 53 Grade B or approved equivalent.

Exception: In Seismic Design Categories A, B and C, columns no more than 48 inches (1219 mm) in height on a pier or footing are exempt from the bottom end lateral displacement requirement within under-floor areas enclosed by a continuous foundation.

R301.1 Application. Buildings and structures, and all parts thereof, shall be constructed to safely support all loads, including dead loads, live loads, roof loads, flood loads, snow loads, wind loads and seismic loads as prescribed by this code. The construction of buildings and structures in accordance with the provisions of this code shall result in a system that provides a complete load path that meets all requirements for the transfer of all loads from their point of origin through the load-resisting elements to the foundation. Buildings and structures constructed as prescribed by this code are deemed to comply with the requirements of this section.

 

[TimNY]

Nice permitguy... I think we got 'em coming and going.

 

[steveray]

PG and Tim Nailed it...

 

[globe trekker]

Much thanks to you all for your input! Ya'll are "the best!"

The listed sections will do nicely!

.

 

[steveray]

Now if we can just get them to put allowable column loads in the IRC.....

 

[brudgers]

R802.11 Roof tie-down. "A continuous load path shall be designed to transmit the uplift forces from the rafter... to the foundation"

"Foundation? I was just plannin' to use the slab."

 

[RJJ]

I just had the same issue and use the sections referenced.