Gap between insulation, DPM querys

[PeterW]

+1 to what @Russell griffiths Has said. 

 

Use a 6:1 sand cement screed to level the floor as it probably has a slope, DPM and EPS and chipboard flooring. 

 

Did a garage floor like that and it’s warm under foot and easy to do. 

[ninja432]

27 minutes ago, Russell griffiths said:

Ok so I’m going to mess with your head a bit. 

@ninja432

how about a floating floor, it used to be popular, and if this is just an office ,gym type room would be more than adequate. 

 

Eps insulation, laid on concrete floor, moisture resistant tongue and groove chipboard on top all glued together to make one big sheet, edges held down by skirting. 

No joists, no hangers, no screwing or packing, 

It would depend on the quality of the floor underneath 

When you say quality of floor, do you mean how level it is? it looks a little bumpy in places.

[Jeremy Harris]

As well as being a bit rough, the chances are that a garage floor will have a slope.  It's quite common for garage floors to be built with a slight slope out towards the door.

[ninja432]

Ok, these plans with the screed on top of the insulation or the concrete first and then insulate and board are all sounding good. However I haven't worked with cement much and don't trust my abilities to get it level. I have worked with timber and that's where I feel confident. So it's the Hanging joists with support plan for me. 

 

My conundrum now is how to support the insulation between the joists. With only a 50mm ventilation cavity underneath, applying a Vapour Permeable Breather Membrane, underneath the insulation, sounds a bit tricky. So maybe using insulation netting is the way to go. 

[PeterW]

8 minutes ago, ninja432 said:

Ok, these plans with the screed on top of the insulation or the concrete first and then insulate and board are all sounding good. However I haven't worked with cement much and don't trust my abilities to get it level. I have worked with timber and that's where I feel confident. So it's the Hanging joists with support plan for me. 

 

My conundrum now is how to support the insulation between the joists. With only a 50mm ventilation cavity underneath, applying a Vapour Permeable Breather Membrane, underneath the insulation, sounds a bit tricky. So maybe using insulation netting is the way to go. 

 

Is any of this being done to building regs ..??

 

You don’t have the ability to put a membrane or ventilation under a floor the way you are doing this. What is the total depth you’re trying to fill between existing floor level and the existing garage floor ..??

[ninja432]

I am hanging the joists from the walls. With a 50mm ventilation gap underneath. DPM on top of the joists. 

 

I don't fully understand your last question "between existing floor level and the existing garage floor"

 

Do you mean between the existing floor level and the new floor? if so, I'm probably going for 100mm deep joists (also supported from underneath) and insulation. Then 22mm flooring.

[PeterW]

Is this a conversion of an internal garage ...?? 

 

If you are supporting the floor on slate packers then your hangers are redundant. 

 

Can you take 10 mins to sketch the plan for this as we are all struggling to understand what you are trying to actually do here. 

[Russell griffiths]

Got a picture, 

what sort of budget have you got ?

you could insulate it and then get a company in to lay a screed over it.