Extending deck beyond existing beam

by Mike

I have a deck that is 49' by 10' and want to extend to 16'. Another 6' further out from the house.

Do I have to move the support posts and beam the currently holds up the deck? Or can the deck be extended with the posts and beams remaining in place?

I live in Loudoun County, VA. Can I get an answer please?

Editor's Comments:

I invite any builder from Virginia or Loudoun County who may have more accurate information, but based on my knowledge the answer is no.

You will have to move the posts and beams because you can not have a cantilever beyond 1/4 the length of the span between beams.

If you figure your beam may already be 12" to 18" in from the edge of the deck and you want to add another 6' outwards beyond that, you are talking about a joist cantilever of 7' at least.

By the way, you would most certainly have to switch the joists to a larger size, say 2x12 or greater.

I think in this case you would probably also have to leave the present post and beams in place and add a second beam to support the extension.

Otherwise you would have a span of say 15'-14' from the new beam to the ledger. This also implies again - maybe you will need bigger joists than just 2x8 to span that distance.

Wish the news was better. But this will be much much safer. Again if anyone else has some other information that corrects what I have said, please say so.

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