I'm working on a deck with a lot of level changes. Using 4x4 posts for the railing is undesirable because it'll look rather clunky.

I am wondering if there are any examples someone can point me to where a different, thinner post size is used. I can't seem to find any (possibly because it isn't possible to do it without it being too flimsy). Would a possible alternative be to use multiple, thinner posts? I doubt it as the real problem is people pushing on the railing... Hopefully this question is specific enough to warrant an answer.


  • If you're willing to mix materials you could use a steel post for the railing that is much thinner than 4x4.
    – Hank
    Aug 11, 2015 at 16:45

2 Answers 2


Typical wood deck railings are 4x4 posts, 2x4 rails, 2x2 balusters and a 2x6 railing cap on top. Wood railing is chunky but it needs to be to prevent people falling through it in the event of a accident. It is not just leaning that is the concern but 1 or 2 200+ lb people failing into the weakest spot (middle of the rail) that it needs to handle. But when it is done right, stained a nice color, sealed and has quality work, it does look very nice. You can upgrade the look by having post caps or switching out the wood balusters for metal ones for not much more.

If you want thinner posts you need to switch materials, like metal, but that will probably double your costs. With metal posts, come metal rails which then require metal balusters. All this metal requires a metal worker to fabricate offsite and then bring to site for assembly and install.

  • There are some metal railings at the big box stores that are not awful. Look for 1-1/2" posts and a sturdy mounting system. (There are ones that are absolutely awful, too, so choose carefully.)
    – User95050
    Aug 12, 2015 at 0:28

I’ve used 2x10 s for vertical supports They have lots of contact/ surface area to attach to stringers or band joists. I think 4 bys have become the standard by default. 2by don’t have to be notches and seem effective

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.