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concrete foundation blocks

Donna65
Finding My Feet

concrete foundation blocks

Hi everyone, 

im attempting to build a deck off my concrete verandah and was thinking about using concrete foundation blocks for my footings.

Has anyone used these before and would love to see photos.  Trying to do on my own and wanting to do it as easy and as safe as possible. YouTube is my friend lol.

DCB608DD-9B82-427F-B3DF-3A908727153E.jpeg

 

202A8D10-DDB3-41FF-939F-E92E90C2A9A3.jpeg

 

Jason
Community Manager
Community Manager

Re: concrete foundation blocks

Great project @Donna65, we are looking forward to seeing how it progresses. I’m sure there will be helpful and experienced members like @Adam_W who can assist you with advice about your deck footings.

 

Have you seen this post - https://www.workshop.com.au/t5/Best-of-Workshop/Top-10-most-popular-deck-projects/ba-p/30303 - it should provide plenty of inspiration for you.

 

Welcome to Workshop.

 

Jason

 

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Brad
Kind of a Big Deal

Re: concrete foundation blocks

Not used them myself and there are several plastic alternatives.

https://www.bunnings.com.au/deko-250-x-150-x-150mm-instant-concrete-foundation-block_p1080391

I have used these and will again.

https://www.bunnings.com.au/good-times-100mm-modular-decking-adjustable-support-foot_p8451185

Not much of a view of them but I used 4 on the left hand side where the slope was too great to dyna bolt the brackets on.

image.png

Adam_W
Workshop Legend

Re: concrete foundation blocks

Hi @Donna65 sounds like a fab project!

I haven't used pre-made concrete foundation blocks or their plastic counterparts myself.
Personally I see the issue with such options as not to be with their stability but with the soil beneath.

Soil, especially any soil with even a small amount of clay in it, can be what they describe as reactive – it swells or contracts depending on moisture levels. You can see this in a house where an extended dry period can cause cracking in walls or in a slab.

Pouring basic footings is actually pretty easy especially now that you can get higher MPa rapid-set concrete in bags. MPa is the rating of compressive strength and most rapid-set products are sub-20MPa.

For structural strength, such as footings, you want at least 24MPa. Lately for anything like this I’ve been using 32MPa rapid-set & it’s awesome.
I’ve found the easiest way to build a deck etc. is to dig the holes for your footings, build the main framework, raise it up to the right height, get it level, attach the posts & hang them into the holes and then just concrete them all in at once.
For a small deck you’re only going to need around 2 to 3 bags per hole.

I’ve included a quick pic of a typical footing head using 90mm post and gal stirrups. This sort of structure can still be impacted by soil movement but not the way surface blocks may be.

As with anything howver it's all down to suitability for different situations.


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Jason
Community Manager
Community Manager

Re: concrete foundation blocks

Great advice as always from @Adam_W. Many thanks for sharing your expertise with the community Adam.

 

@Donna65 - You might also find the information in this previous discussion helpful - Low level deck

 

Jason

 

 

 

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Re: concrete foundation blocks

Low Level Deck. Easiest way without concrete footings is Tuff Blocks.

https://www.youtube.com/f621ea2e-102d-462b-8f59-ebc9d01da6a1

Stratco/Bunnings sell them.

Good luck

Re: concrete foundation blocks

Thanks for joining in the discussion @AlanBrady1983. Great to see you join the community and make your first post. It sounds like you have some great knowledge and experience to share with other members. I trust you will also receive plenty of useful information, advice and inspiration for your projects from the community. Feel free to post anytime you need a hand or have something to share.

 

Welcome,

 

Jason

  

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