Lag bolts vs thru bolts

[JStructsteel]

What experience/opinions do you have on Lag bolt vs Thru bolting heavy timbers? I have heard lag bolts is no-no, but recent reading seems to change my mind?

Thoughts?

 

[Tmoose]

I'm going to have to rebuild the multi-family mail box stand at the end of the road. again.

I'm thinking of using split ring connectors in addition to the steel reinforcements it has.

file:///C:/Users/DTimberlake/Downloads/Item-S-3b.pdf

 

[Triangled]

I think that either is OK, IF designed and installed properly.

The lag bolts have a double pilot hole requirement, if I recall correctly from NDS, that is fairly often overlooked by 'get-er-done' carpenters. check NDS.

 

[XR250]

Lags also have small design values IIRC.

 

[OldBldgGuy]

Triangled is right: IF designed and installed properly

 

[Ron]

Agree with Triangled. Be careful of the source of the lag bolts though. Some are fairly crappy. More recent thinking is to use high strength screws like Simpson SDS. I still design some connections with lags. Sometimes (and often) you just don't have access to thru-bolt.