Floor Insulation

[Fifediy]

Hi

I'm in the process of converting my garage into a dining room and have a couple of queries.

Planning officer has stated that I require a floor insulation of 100mm recommending Kingspan TF70. My problem is that the floor will then be approx. 25mm higher than my original flooring leading into the kitchen.

I would obviously prefer the floors to be level but they refuse to budge at the moment. Is there any other way I can achieve the same U value by using a thinner material?

Current floor is 125mm concrete.

Any information would be appreciated. Thanks in advance.

 

[freddiemercurystwin]

Generally they will let you add a little extra to the roof or walls to compensate. You mean Building Control btw.

 

[jeds]

Regardless of what the BCO says your responsibility is to achieve the minimum U-value - which I believe is 0.20 in Scotland? 75mm Kingspan K3 board should achieve that but it depends how many exposed walls you have. Otherwise you can use a procedure called 'compensatory approach'. That's just what it says on the tin. You could have a floor slightly worse than the strict requirement but compensate for it elsewhere. As long as the overall heat loss would be the same you would comply. Having said all that, it sounds to me like your BCO really needs to get a life.

 

[jeds]

I hate it when that happens.

 

[tony1851]

English building regs specifically state that a lower level of insulation may be acceptable if the normal standard would cause problems with floor levels.
Is there a similar stipulation in the Scottish regs?

 

[Fifediy]

Regardless of what the BCO says your responsibility is to achieve the minimum U-value - which I believe is 0.20 in Scotland? 75mm Kingspan K3 board should achieve that but it depends how many exposed walls you have. Otherwise you can use a procedure called 'compensatory approach'. That's just what it says on the tin. You could have a floor slightly worse than the strict requirement but compensate for it elsewhere. As long as the overall heat loss would be the same you would comply. Having said all that, it sounds to me like your BCO really needs to get a life.

We have one external wall which he is allowing to be insulated with 42.5mm kingspan k18 and the new wall (ex garage door) is to be 90mm Kingspan TW50 between new studwork 30mm Kingspan TW50 to face of new studwork. We have not been asked to insulate ceiling which I presume we could to meet the standard?

Thanks to all for your input.

 

[DevilDamo]

If you jump onto the Celotex website, use their online u-value calculator, input the P/A (Perimeter/Area) figure and see what floor insulation thickness that recommends. Normally you'd be looking at 70-80mm to comply. You'd normally see approx. 100mm for a higher thermally efficient building.

And as mentioned, you can normally compensate increasing the insulation to other thermal elements in order to comply if you are restricted, e.g. floor levels.

Btw, this does relate to the English regs. Not sure how much it differs in Scotland.