Polystyrene sheets or foil backed for a shed floor?

[Hightowermark]

Hi,

Just looking for some advice before i purchase it. I'm building a garden shed 3mx2.4m And the base is raised off the ground on blocks by 8" or so. The base is 4x2 treated. So as i'm storing items in here as well as tools etc. Would like to insulate the floor before i put the OSB down.

Now would foil backed be worth it for this purpose? I'm going to wrap the shed in a breathable membrane before cladding it. So i could use this (reversed) before the OSB floor.

The cost between them is double so as this won't be a living space would the polystyrene sheets at 100mm be adaquate?

Thanks

 

[dontbelieveawordofit]

yes

 

[Hightowermark]

Yes to which part

100mm Polystyrene Sheets adequate or foil backed worth it?

 

[Alexnh]

It reads to be as 100mm polystyrene is sufficient. Spend the savings on upgrading to plywood flooring.

What function would the reversed breather membrane serve on the floor?

Remember to put a damp proof layer between the blocks and the wooden base

 

[Hightowermark]

Thank you. Yes that is what i have gone with.

I have seen a few videos that have done this, would it not do anything? I will have loads of membrane left over so it won't be a cost factor.

Yes i have already done that thank you.