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How to make a subfloor in garage?

Hello Brains Trust,

I am in the process of construction a sub floor as i need to raise my garage to create a work from home salon space covering will be floating floors 5mm wet area .

Council have instructed we need to bring the floor up 50mm

current process was to

1) use VBS rapid to paint surface first

2) lay h3 treated pine 90x35 the length of garage with 450mm spacings then add noggings *** Glue and then bolt into concrete ( bolts haven't yet decided but I will counter sink them)

3) then paint tops then glue and screw structural ply

4) lay hybrid planks 5mm

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Jason

Apologies for the slow reply @nicksom.

Let me tag some helpful members who might be able to kick off this discussion and give you some assistance: @Nailbag, @AlanM52, @Dave-1, @DIYGnome.

One of our resident Bunnings D.I.Y. experts will also be happy to help as soon as possible.

Jason

Dave-1

Good morning @nicksom

I am wondering if you could attach some pics of the area you are talking about that you want to raise the sub floor.

An overall picture

Maybe one from both sides

And any that may show extra things that may need to be considered.

Your option 2

"lay h3 treated pine 90x35 the length of garage with 450mm spacings then add noggings *** Glue and then bolt into concrete ( bolts haven't yet decided but I will counter sink them) "

Are you intending to lay the timber directly on the concrete? If so I would be hesitant to do so as an air gap would be wiser to help stop any deterioration over time. Also By raising the floor, how much space above the floor height to the ceiling will be left?

Dave

AlanM52

Hi @nicksom,

As per @Dave-1's request some photos please.

Cheers

EricL

Hello @nicksom

Thanks for sharing your question about your subfloor in your garage. How much space do you have to increase the floor height? Using the materials you mentioned the floor will increase to 108mm++ conservatively which is more than the 50mm the council has requested. I propose asking the council for an approved materials list and if they need a floor framing plan that has been certified by a draftsperson or engineer. I would also ask it the floor is ok to increase by that much or if it has to be exactly 50mm.

This will save you from going back and forth in regards to approval. You'll also be able to find out if the VBS rapid is an approved moisture barrier. I would also like to ask for an image of your flooring. It will give our members a better idea of its condition, we can them make further recommendations on What materials to use.

If you have any other questions we can help with. please let us know.

Eric

Nailbag

G'day @nicksom

I have essentially done the same project as you, just turning a single garage into a formal entrance.

I twas able to take an easier option that I wonder if you have considered, which is to lower the groundwork in front. This is a much easier process where I installed an ag drain under and infant of the entrance the built at floor level a deck. Being non-solid and with a 50mm clearance plus drainage it complied with building regs.

Nailbag

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