Making box steps out of 4x8 PT, how many lag bolts?

[drumz]

I'm making box steps out of 4x8 pressure treated lumber with each one sitting on the other down to my driveway 4' below the front step to the house. I'm planning on using 5" x 3/8" lag bolts but not sure if I can get away with 2 for each end or if I should go with 3.
Thanks in advance for your time d;-)>

 

[bud16415]

I would use 3” deck screws.

 

[drumz]

I would use 3” deck screws.

It's 4x8's, 3" are not long enough! My question was how many, thanks.

 

[bud16415]

Sorry I misread, so used to reading 2X.


Your question is hard to answer as we don’t see the design. But in general two lag screws properly installed will be very strong.

 

[oldognewtrick]

What about making lap joints?

 

[nealtw]

5" is not long enough, 6" maybe.