New Garage Floor Position

[Strubo]

Hi, im about to start converting my garage into a gym. The walls are already insulated and plasterboard to the same spec at the rest of the house. The floor is concrete. I plan on creating a timber frame floor 100mm in depth using 2x4 with 100mm PIR in the cavities. 22mm caber deck T&G on top of the frame. 
 

I have read that the new floor frame should be 10mm away from the existing garage walls and 10mm away from the bottom of the plasterboard. I did plan on putting the new floor underneath the existing plasterboard, however that would mean trimming the bottom of the plasterboard and it will make it more awkward fitting the T&G boards. 
 

My question is should the frame be 10mm horizontally away from the existing wall (blocks) or could it be 10mm away from the plasterboard.

 

Thanks in advance for any assistance. 

[Nickfromwales]

If it's for gym equipment then I'd put 25mm of XPS insulation down, a DPM, and then order a concrete truck to fill you up and have a solid floor.

 

You can put those interlocking floor mats down to give a bit more 'warmth' underfoot and to create a finished floor. I'd avoid doing this in timber as if you drop a weight it'll defo just bash a hole in the chipboard flooring.

[Strubo]

Thanks Nick, might be a bit late for the concrete as I have already ordered all the materials. I’m putting 20mm x 1000mm x 1000mm rubber gym floor tiles on top of the T&G flooring. Haven’t ordered the tiles yet, so could go to 30mm

[ETC]

Don’t put a timber floor in. It will sweat like mad and the timber will rot unless you ventilate the floor. Do as Nick says - floor finish on VCL on insulation on DPM. 

[Strubo]

I have already have all the materials. I am putting a DPM down first. 

[Conor]

3 hours ago, Strubo said:

I have already have all the materials. I am putting a DPM down first. 

Most places will take them back for a restocking fee .

 

I've a small gym area on 50mm screed on insulation. It's bouncy and I would not trust a timber floor. I'd be going as nick says. And it'll be done faster and minimal price difference.

[ETC]

2 hours ago, Strubo said:

I have already have all the materials. I am putting a DPM down first. 

You’ll be pulling it up in a year.

[G and J]

If you are dead set against a concrete floor why not do a floating double layer wood floor over high compressive strength EPS?  That way you only have to return the 100mm timbers. 

 

I think a vapour barrier under the wood floor would stop condensation under the EPS and if you used 75mm insulation you’d end up with a similar floor level.

 

I don’t think even two later caberdeck would withstand a large weight dropped from height but most peeps home gyms focus on machines and relatively light weights anyway.   (Actually I used to use free weights and I think it’s awfully bad form to drop weights anyway, but that’s another story.)

 

But rowing machines, treadmills, cross trainers, etc. would be fine.

 

And that should leave spare cash for the most important bits, huge tv, sound system, mirrors, etc….   😉 

[Nickfromwales]

2 hours ago, Conor said:

Most places will take them back for a restocking fee .

👆👌.

 

5 hours ago, Strubo said:

Thanks Nick, might be a bit late for the concrete as I have already ordered all the materials. I’m putting 20mm x 1000mm x 1000mm rubber gym floor tiles on top of the T&G flooring. Haven’t ordered the tiles yet, so could go to 30mm

It’s just some wood etc, time to decide!

 

2 layers of 22mm caber glued and screwed together may beef it up, just stagger the joints.

 

In case you’re curious, zero joins with concrete 😜.