Simpson HDU Hold Down Minimum Member Interpretation

[meamin]

Hey all!

Having a bit of trouble interpreting the minimum size table.

The general notes say that the tabulated loads are based on installation into the wide face of a minimum 3 1/2" wide (2x4 stud qualifies).

The graphic for "vertical HDU installation" clearly shows a stud pack, specifically(3)-2x studs.

My confusion is with the table as we get to HDU8,HDU11 and HDU14's.

DTT1Z...Min wood member size = 1 1/2 x 3 1/2. So a (1)-2x4 or (1)-2x6 qualifies for the listed loads.

HDU5-SDS2.5...Min wood member size = 3 x 3 1/2. So a (2)-2x4 or (2)-2x6 qualifies for the listed loads.

HDU8-SDS2.5...Min wood member size (for 7,870lbs) = 3 1/2 x 4 1/2. So now it's a min 4x5? Seems like they are listing thickness first so the smallest 6" nominal that works would be a (3)-2x6?

HDU11-SDS2.5...Min size for max 11,175lbs = 3 1/2 x 7 1/4. So a 6x8 needs to installed for a 6" wall.

HDU14-SDS2.5...Min size for max 14,445lbs = 5 1/2 x 5 1/2. So a 6x6 or (4)-2x6?

Does the consensus agree that I can replace the solid posts with an equivalent stud pack? What's with the HDU11 not providing a 6x6 option?

The simpson hold down designer only suggests post sizes in the table. Wish it would give you an equivalent option for 6" nominal walls.

 

[meamin]

Ok, I do see that the hdu11 gives 9,535lbs for a 3 1/2 x 5 1/2. So there's the 6x6 option.

 

[lexpatrie]

You can do that but the holdown is not going to spread the load equally to all plies, you need to connect them adequately to share the load.