Simpson TB Screw Alternative?

[DanLNY]

Hello all,

I need a product similar to the TB screw by Simpson (

http://www.strongtie.com/products/fasteners/TB-screw-loads.html

). My issue with the TB screws is that the steel member I need to connect my timber nailer to is 3/8" thick, and it will be located in an outdoor environment. I called Simpson and was told that these screws are only to be used on indoor applications, and on steel up to 5/16" thick only (as shown on the website). I also called Hilti and the woman on the phone didn't really understand what I was asking for and sent me information on metal to metal connections. Does anybody know of an alternative product that may work in my application?

 

[BAretired]

How about cadmium coated or galvanized screws or bolts?

BA

 

[DanLNY]

I'm sure those would be fine, I need to find/specify a product that can go through a 2x and a W8x24 (3/8" flange thickness).

 

[DanLNY]

I forgot to mention that I am looking for a product similar to this because I would like to avoid field drilling the top flanges. A self tapping screw that can go through the two materials (instead of drilling with a nut/bolt) will save a lot of time/money.

 

[BAretired]

For wood nailers, I have always used 3/8" bolts at 4' centers staggered unless otherwise specified. For an exterior environment, they would be cadmium coated or galvanized.
The holes are shop drilled in the steel beam flange, not field drilled.

BA

 

[DanLNY]

I think I might have to go this route, do you typically countersink the bolts into the nailer?

 

[BAretired]

Not usually because nailers are normally used to provide an attachment for joists which should be positioned to miss bolt locations.
If something is bearing at the same location as a bolt, countersink as required on site.

BA

 

[hokie66]

Use galvanised bolts. The cadmium plated ones don't last long in exposed environments. You won't find a self drilling, self tapping screw for 3/8" steel. Even when using the TB screws shown in thinner metal, you lose a lot of screws without predrilling.

 

[DanLNY]

I'm going to be using galvanized bolts, and I will be countersinking them as I have decking that is going to be layed out on top of the nailer/joists.

 

[SteveGregory]

Since the beam and wood nailer is outside, I would assume that the nailer is pressure-treated. In this case, I would consider using a stainless steel or at least a hot-dipped galvanized bolt. I would also use a barrier membrane between the nailer and the steel beam or galvanize the beam also.

Grace makes a membrane called Vycor® Deck Protector. Simpson has a FAQ on pressure-treated wood and connectors at:

http://www.strongtie.com/productuse/ptwoodfaqs.html

 

[DanLNY]

I am already specifying that the beams be galvanized as well, thanks for the info on the membrane, that's an interesting alternative for future applications.