maximum heights for wall studs? 5

[EngineerofSteel]

What is the max height for a wall stud?

How high can a shear wall be using 2x6's?

A man wants to remodel his family room, increasing the wall height to 19' from 10'. Currently, he has 2x6 DF#2 studs @ 24" o.c.

Where is this ratio limit in the UBC?

 

[csd72]

It is controlled by strength and deflection which will need to be calculated in accordance with your code.

For that height I would expect 8" studs would be required at the minimum, possibly high strength timber/glulam.

19' is far above a typical floor height so I doubt you will find a specific reference to this situation anywhere.

This is why you spent 4 years in college studying engineering, not so you could look up the IBC all the time but so that you could use engineering knowledge to solve problems that are beyond the scope of the normal.

 

[EngineerofSteel]

csd72,
Thanks. I am already finishing the calc. I think what I was looking for is a "rule of thumb" I once heard referenced by an old engineer I know. I'll ask him.

 

[msquared48]

You need to throw out the "Rule of Thumb" here as the size of the wall studs is too dependent on too many variables.

To name a few... Local snow, wind, and seismic conditions, bearing or non-bearing walls, length of shear wall (3.5:1 aspect ratio max), materials used.

At 19 feet plate height, the min SW length (plywood) is about 5'-5".

At 19 feet, the stud sizes probably are controlled in deflection by the wind or seismic loads parallel with the major axis of the studs. If you have sheetrock on the inside, I would recommend l/360 max for wind/seismic, yielding a max 5/8" lateral deflection normal to the wall face.

Mike McCann
MMC Engineering

 

[EngineerofSteel]

Thanks, msquared.

 

[civilperson]

Use composite wood panel design with both faces of wall as flanges and inner stud as web for calculating I. OSB or plywood of some nominal thickness attached to the studs with adhesive and nails will give sufficient shear strength. The exposed face can be what ever the decorator requests, attached to the interior plywood/OSB.

 

[bylar]

When you are asking about the height for a shear wall make sure you have the correct aspect ration but with that height you have to consider the lateral loads. Most codes require a min of 10 psf but you need to check the wind loads in your area and the vertical loads the wall is supporting.

 

[tngolfer]

Are you removing the existing studs and replacing them with new studs?

You don't want to have a hinge at 10' where you have new studs taking off of existing studs.

I agree with Mike. There should be no rule of thumb. There are way too many variables, especially for a stud of that length.

 

[EngineerofSteel]

tngolfer,

I specified 3/8" CDX both sides. One side exists already. The new paneling will be added to the interior.

My plan to cancel a hinge is to remove and replace the (E) paneling so that the panels cover the hinge; panels will bridge over the connection.

The new panels will do the same. The bending moment will transfer through the sheets.

All: I have two wall sections, full-height to provide shear. Each is 7' 1.5" inches in length. So, the needed ratios are observed.

Thanks.

 

[msquared48]

Repacing the paneling to eliminate the hinge is not a good idea structurally speakling, particularly at only 3/8" thick on both sides. The knucle joint is still going to exist.

The best way is to add new full height studs that will be able to span the load WITHOUT depending on the 3/8" plywood paneling.

In lieu of that, sistering on new 8" long studs, 4' on either side of the splice, could work if they were nailed and glued properly to the existing studs.

Be mindful though that you may have to increase the full height studsize at the ends of the shearwalls anyway for the holddowns.

Mike McCann
MMC Engineering