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Concreting under a garage

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Concreting under a garage

Hi... I've got a metal garage with a tiltadoor. I want to put a concrete slab in it, so it can serve as a workshop. 


I'm wondering what approach is best. Should I:

- Jack the garage up, and pour concrete? 

- Roll the garage onto its side, and pour? 

- Move the garage away, then pour? 

- Dismantle the garage first? 

- Put the slab somewhere else, then roll the garage onto it? 

- Pour inside the existing garage? 



Junior Contributor

Re: Concreting under a garage

Hi Geoff. It just so happens that I've done this exact thing. I had the slab poured inside the shed. The main consideration was to put a barrier between the concrete and the Colorbond because I was advised that if they were in contact it might cause the Colorbond to rust at the bottom. We had plastic sheeting under the concrete and ran this up the sides of the shed far enought to create a barrier, then trimmed it back later. There was timber formwork as well.


This worked perfectly. There were no issues and no rust subsequently. I'm no expert but it has been a good solution for me.

Trusted Contributor

Re: Concreting under a garage

Done 2 sheds at home with concrete, didn't use plastic and have had no trouble with the galv sheets rusting, rails is something else termites have had a field day on some of the bottom ones. Cement both sides has kept the walls in place.

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