Exterior Column built with metal studs

Question on exterior walls or columns being built on exterior slab. The drawings do not show exterior wall details. Metal studs are shown to build the column and cover with exterior gypsum sheathing and stucco. I have issued a correction to the contractor to supply a curb to place bottom track of metal stud. the only reference I could find in code at the moment was the weep screed termination 2" above concrete slab. Do any of you know of another reference in CBC that I could use? Roll Eyes
Original Post
Send the contractor back to the signer of the approved plans, or call the Plaster Instatute and get their booklet. Regardless it being metal or wood if the wall is having stucco the weep screed distance is required.

Before the 2 inches was in the code, AHJ's use a number of measurements to get the weep screed to have an air space. At one time in the code the weep screed was only used in conditioned space. So a unconditioned garage building would not have to have it. The weep screed is used more for keeping water out and off the building walls. Termite control would be the 8 inches needed from earth to wood seperation.
Termites will build their conduit and travel anywhere the want.
You are correct if you are in California, but only for wood structures per CBC;

2304.11.2.8 Separate wood framing. [SPCB]
Correct the conditions in frame and stucco walls and similar appurtenant construction so that the wood framing is separate from the main structure by a complete concrete or masonry plug with no voids that will allow infestations to enter the structure from the wall. If there is no plug, the foundation shall be 2 inches (51 mm) or more above the grade levels and at least as high as the adjoining slabs or 4-inch (102 mm) concrete barrier seat off  installed.

and IBC 2304.11.2.2 for other stuff.

The distance from grade to the exterior plaster screed is what forces this as a solution even though the curb isn't actually a "descriptive requirement" in the code, just as you thought. Note that the distance is 4-inches at landscape areas and 2-inches to hardscape [a concrete mow strip will qualify for this].

As designers of DSA-regulated projects, we always indicate curbs at these locations [and incidentally at every exterior building wall where the floor is at or close to grade]. This is to keep termites and other vermin out of the building as well as to reduce water "wicking" up the plaster or paper backing.

While in this instance the building department comment is sort-of vindicated by the code, I shudder to think that AHJs issue "corrections" without being sure they are actually needed.

Mike E
Typical light gauge steel metal studs are listed for dry location only by MSMA (Metal Stud Manufacturers Association) ICC report. If the studs have a manufacturer that can be identified, then see if they are part of the MSMA. The report is available on the ICC website.
Otherwise take a look at the conventional construction provisions in the code, there are metal framing requirements for light gauge steel.
I spoke too soon: weep screed distances above grade are also set in 2512.1.2:

2512.1.2 Weep screeds.
A minimum 0.019-inch (0.48 mm) (No. 26 galvanized sheet gage), corrosion-resistant weep screed with a minimum vertical attachment flange of 3½ inches (89 mm) shall be provided at or below the foundation plate line on exterior stud walls in accordance with ASTM C 926. The weep screed shall be placed a minimum of 4 inches (102 mm) above the earth or 2 inches (51 mm) above paved areas and be of a type that will allow trapped water to drain to the exterior of the building. The water-resistive barrier shall lap the attachment flange. The exterior lath shall cover and terminate on the attachment flange of the weep screed.

Mike E
Thanks. The studs are 16 gauge used on this project for all curtain walls etc. The column in question is non bearing in a slab service area on the exterior of the structure. Curbs are shown for other portions of the building just not designated for this area. Keep in mind the column is yet to be built. I am requesting the curb prior to light gage metal studs.
Likes (0)