Replacing subfloor - Which material to use?

[benjy_b]

Hello all,

My girlfriend and I are carrying out a substantial renovation to the "west wing" of our bungalow. This will involve insulating below the floor and replacing the chipboard subfloor.

We are weighing up the costs of what materials and insulation to use for the subfloor.

What are our options for subfloor materials and the pros/cons of each?

I've come across the following so far:

- Softwood
- Hardwood
- Redwood
- Whitewood
- Plywood
- Chipboard

We're considering using Softwood, but with an intention to lay a floating wood/laminate/engineered wood floor over the top. However, my girlfriend has her doubts about the high cost considering it would be something that will not be seen.

The size of the area is 30.79 sqm.

Our joists are 75x220mm with 400-450mm centres.

Here is a picture of our floor plan. You can see the "west wing" on the right. We plan to fit our en-suite/wet room (the grey tiled room) with aqua board at the same time.




With regards to insulation, we like the idea of sheepswool suspended in a netting.

How would I go about calculating the optimum thickness to achieve a U value of 0.25?

 

[vinn]

If its possible why not carefully remove the chipboard and go back with chipboard, replacing any damaged sheets?
T&G sheets of chipboard or OSB are good for purpose and cheap, ply is more durable and more expensive.
Dont go near the other possibilities you mentioned. More expense and lots more work.

Call Kingspan ref the insulation and talk to a tech if nobody comes up on here.

 

[benjy_b]

We really don't want to put the chipboard back down.


We're wanting to upgrade to a more premium product and don't mind any additional work/cost. We're after a better end result.

 

[freddiemercurystwin]

T&G plywood with plenty of screws to avoid squeaks, its a no brainer really, chipboard is best avoided and you wish to avoid it anyway, forget OSB its OK for a shed but not here, the others are just expensive and pointless if they'll not be visible. Mark any pipe/electrical runs on the plywood as you go There are thousands of threads on here detailing how to insulate the floor.

 

[freddiemercurystwin]

//www.diynot.com/diy/search/4666151/?q=chicken&o=relevance&c[user][0]=46858 there are lots of others if you search

 

[benjy_b]

Thanks!

Where does "chicken" come into it?! Lol

I've sorted the insulation, 111mm to achieve a U value of 0.25.

Worked out by an online calculator.

We're going to go for 150mm Sheeps Wool.

 

[freddiemercurystwin]

Chicken wire can be used to suspend the insulation!