If I want to have a granite countertop as a table on top of my deck, do I need to support the 4 corners with actual footing, like 4x4 with concrete? Or it is possible to just bold the 4 legs on the side of the joists?

I have not weight my granite yet but according to this, it is 12.8 lbs sq ft


Mine is like 3' x 9'

I am inspired by this, as I have no design yet.

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I don't have the grill in my case but the countertop will be close to the railing. So for 4 corners of the 9 foot long countertop, are they supported by footing below? Or the legs are just standing on top of the joists underneath? UPDATE 1

This is a free standing deck. Conveniently, two legs of the countertop if supported by the posts already. So the question is do I need the other 2 legs supported by posts? Or can they just sit on top of 2x8 joists that are on top of 4x8 beam?


1 Answer 1


Assuming your deck is somewhat modern and properly designed and built, it can easily handle a live load of 13 pounds per square foot (no extra footings required, no need to worry about aligning the table legs over joists, etc).

That said, I am assuming your deck is somewhat modern and properly built. You should consider paying a structural engineer to take a look at your deck (especially the ledger connection to the house, which is a typical weak spot). That would be a lot cheaper than pouring new footings and going crazy overbuilding it, plus it will give you a piece of mind. You might be surprised how inexpensive a structural engineer costs to take a look at your deck and give an opinion.

  • Hi I have updated my question with more information. This is a new construction so I can pour as many footing as I want. It's actually easier thay way in a sense.
    – HP.
    May 26, 2016 at 18:12
  • 1
    Okay, if it adheres to the IRC standard (assuming you are in the U.S.), then it will have 10 psf dead load capability and 40 psf live load capability minimum. And most decks are stronger than that. 13 psf would not really need special footings. You might consider using 6x6 posts with thicker joists, to beef up your deck though.
    – alfreema
    May 28, 2016 at 2:36

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