How to remove timber footings to concrete?

[pipersdj]

Hi,

I'm in the process of removing an old deck and replacing it with concrete. I have 35 of these footings, and I wanted to know if it's safe to cut them off at ground level and then pour concrete over them. It's a huge job to remove them completely. I plan to cover them in plastic to prevent deterioration, and I was also going to paint the exposed timber.

The slab will be about 20 cm thick, so I'm hoping this approach will be okay, I just can't bring myself to dig out all 35.

Thanks,
David

[MitchellMc]

Welcome to the Bunnings Workshop community @pipersdj. It's terrific to have you join us, and many thanks for your question about creating a concrete slab.

You’ll need to make sure the ground is properly compacted before you pour your slab, so as long as the compacted layer finishes flush with the top of the timber footings, I don’t see any issue with leaving them in place.

Even if the timber eventually rots away over time, it’s very unlikely to compromise the integrity of the slab, especially with a 20cm thickness.

Please let me know if you have any questions.

Mitchell
 

[pipersdj]

Thanks Mitchell.

I'm cutting the posts down to ground level, so the concrete will completely cover them.

[Noyade]

G'day @pipersdj 

I've seen hundreds of threads on this site showing people building decks on concrete and dirt/grass.

I'm just curious as to why you're going the other way?

I don't own a deck - but I have opinions on them based on what I've seen here.

Cheers and good luck with the concrete.

[pipersdj]

I have had the deck for nearly 20 years, and it's time for something easier to look after.

We had the deck renovated about 7 years ago and had it sanded back to raw.

The problem with that was that we had dome-head nails. Even though they punched down about 5,000 of them, they still lost the dome.

They started popping, and were like sharp little razors.

I replaced many with screws, I then realised some of the joists wouldn't hold the screws, so I knew I had some rot.

I thought I had a good twenty years, and now I'm going for a concrete slab and porcelain tiles that look like travertine.
The beauty of porcelain is how tough they are, I'm looking forward to less upkeep.