[Topside]

I have 3 rotted 6x6 deck posts that need to be replaced. The posts are inserted in 12 inch diameter concrete footers. The top of footings are 5 to 10 inches below grade and extend down to approximately 24 inches below grade. The posts need to be replaced and I would like to increase the height of the concrete footing to 3 inches above grade and mount the 6x6 posts on top of the footers via galvanised steel base plates. I would really like to avoid pulling up the existing concrete footers which are in good competent condition and so I am considering the following:1) Remove rotted deck post from within footing as deep as possible.
2) Position 12 inch diameter Sonotube on top of existing cured concrete footing to extend footing to 3 inch above grade.
3) Position (2) pieces of 1/2 inch rebar into 6x6 hole in existing footers (after removal of rotted post) as deep as possible but minimum 6 inches and extending up to 3 inches below top of Sonotube.
4) Pour high strength concrete into post hole around rebar, on top of existing footing and to top of Sonotube. The newly poured concrete would be 8 to 13 inches deep.
The top of the deck post (height of deck) is 36 inch above grade.
Questions:
Is this a good plan to avoid removing existing footings
Would there need to be any preparation to top of existing concrete footing (other than adding rebar in post hole).
Any other advice / recommendations greatly appreciated.

 

[Nealtw]

I have 3 rotted 6x6 deck posts that need to be replaced. The posts are inserted in 12 inch diameter concrete footers. The top of footings are 5 to 10 inches below grade and extend down to approximately 24 inches below grade. The posts need to be replaced and I would like to increase the height of the concrete footing to 3 inches above grade and mount the 6x6 posts on top of the footers via galvanised steel base plates. I would really like to avoid pulling up the existing concrete footers which are in good competent condition and so I am considering the following:1) Remove rotted deck post from within footing as deep as possible.
2) Position 12 inch diameter Sonotube on top of existing cured concrete footing to extend footing to 3 inch above grade.
3) Position (2) pieces of 1/2 inch rebar into 6x6 hole in existing footers (after removal of rotted post) as deep as possible but minimum 6 inches and extending up to 3 inches below top of Sonotube.
4) Pour high strength concrete into post hole around rebar, on top of existing footing and to top of Sonotube. The newly poured concrete would be 8 to 13 inches deep.
The top of the deck post (height of deck) is 36 inch above grade.
Questions:
Is this a good plan to avoid removing existing footings
Would there need to be any preparation to top of existing concrete footing (other than adding rebar in post hole).
Any other advice / recommendations greatly appreciated.

I like your plan, just the way you wrote it. :wink2:

 

[HotRodx10]

Sounds like a good plan overall.


I would suggest putting the 2 rebars in opposite corners, about an inch away from the sides of the hole in the existing pier, and then vibrate or rod the concrete in the hole so that it it consolidates around the rebars, before filling the remainder of the pier.


You may also want to extend a bolt or rod from the center of the new top section to give you an attachment point for the new posts.

 

[3onthetree]

Position (2) pieces of 1/2 inch rebar into 6x6 hole in existing footers (after removal of rotted post)

If you are trying to connect the new concrete top hat to the existing pier, this rebar won't do it, it's just sitting in the new concrete.

Thats a lot of work for piers only 24" deep. Some digging, or a combo of dig with any sort of vehicle jack to help raise them enough to remove. Start fresh.

 

[u2slow]

You could probably cut off the old post, compact gravel up to grade, and go with pier blocks. Pier blocks have worked fine for my 20x16' deck and 20x25' carport.