How do you size treated pine timber for workshop floor

[Glen1]

Hello all building a 3 x 4m metal workshop shed and I am going to install a wooden raised (0.5m) floor. Looking to use treated pine H4 100 x 100mm stumps, H3  bearer and joists with Structaflor termite proof particle board over the top.

I am having trouble deciding the sizing and spacing of stumps, bearers and joists.

I am unfamiliar in calculating the bearing weight that may exist for bench, tool chests, planning machines and the like.

Happy to over size but when looking at the standard AS1684 charts I am unsure what would suit me.

Hoping someone can set me in the right direction

Thanks

Glen   .

[Jason]

Heya @Glen1,

I'm sure the Workshop community will be more than happy to assist you with your shed project. Let me tag the wonderful @Brad who might like to kick off the discussion for you. 

Welcome to Workshop. We're looking forward to seeing how your project progresses. Feel free to post anytime you need assistance with the shed build or anything else around the house and garden. We're here to help.

Jason

[Brad]

This late night ramble may or may not be helpful...

Back to my trade school days in the early 80's, machinery was put on concrete and you dyna bolted it down.

Structa Floor has 3 grades the lightweight has recommended centres of 450mm, 600mm for other grades.

Carbatec jointers have a shipping weight of 248kg and take up roughly 650mm in width.

Early morning finish...

Have you thought on what you are going to use as top layer on your floor as moving machines around will damage the particle board.

[Glen1]

Thanks Jason,

Hi Brad thanks for your reply 

Ideally a concrete pad would have been preferred but the location of shed rules out that.

Aware of the shortcomings of the particle board you could possible add moisture as well being and an issue but struggled to find anything else that was termite proof unless I went for pine boards can you suggest an alternative?

Most of my stuff will be on wheels like my tool chest etc. 

After my post I started looking at AS1684 and thinking of over sizing so looking at using bearers 190 x 45 H3 MGP10 spacings at 1.5m Joists will be 140 x 45 H3 MGP10 spacings at 450mm, posts 100 x 100 H4 spacings at 1.3mt.

For anyone who is familiar is this overkill or possibly ballpark or have I got it wrong?

Thanks

[MitchellMc]

Welcome to the Workshop community @Glen1.

I see our fantastic community member @Brad has already given some very helpful advice. I noticed he has a concern that you may damage the surface. You might consider compressed cement sheeting as an alternative in light of Brad’s comments.

Compressed cement sheeting is termite and moisture resistant and has a high level of durability. It would be worth investigating as an alternative over Structaflor if moisture is an issue.

You may already have seen this, but on the Structaflor product information page it lists the product specifications. There is also an installation and design PDF manual at the bottom of the page. The manual lists spacing of stumps, bearers and joists required for the product.

To future-proof the floor, it would be advisable to go with 25mm heavy-duty blue tongue. That would be the highest weight rating of the range and a good idea if you are not sure how much load you are going to place on it. The manufacturer recommends AS1860.2 which lists the Australian standard for particle board floor installation. Nothing wrong with going above specification.

I hope this additional information assists in making your decision. If there is anything else you would like to know, please feel free to ask.

Mitchell

[Glen1]

Thanks Mitchell good suggestions

if i was to use compressed cement sheeting what would I look at to screw the sheets down with?

I take it I would need to use countersunk screws of some sort?