Cavity insulation - Help!

[Walshie]

Hi,

I have 120mm Kingspan K108 specified as the cavity insulation for a new extension as part of a renovation.

I'm keen to insulate really well but understand that the 120mm Kingspan is now subject to a minimum order of 1000m2 - which is bonkers!

 

I'd like to maintain the designed thermal properties - so my question is:

 

Can I double up and use Kingspan 60mm boards? I'm guessing that this will give a very similar level of insulation but wonder if having two boards will create other issues such as creating a draft chimney within the void or similar? Would it be any more of a pain to install than single board etc?

 

Are there alternatives that will have the same thermal properties of the Kingspan?

 

Would really appreciate some help with this!

 

Thanks in advance!

W

[crispy_wafer]

Wider cavity with pumped in eps beads, or wool batts installed as the walls are being built.  Edited to add, just check out some recent posts of PIR being installed in cavities, which is the reason for my suggestion of eps beads or wool batts.

Edited April 18 by crispy_wafer

[Spinny]

@Walshie How big is your cavity and what is the wall makeup ? drawing ?

 

I have 90mm PIR and lots of companies make it. The interlocking design is better.

 

Is this what you are after ? Seems to be around ?

https://www.nationalinsulationsupplies.com/products/kingspan-kooltherm-k108-cavity-board-1200mm-x-450mm-all-thicknesses?variant=48126096146779

[Walshie]

Hi,

Quite a few places advertise it but when you get as far as placing an order they can't fulfill.

I have got a couple of places that do seem to be able to supply - but I suppose I won't really know until order is placed.

I'm looking at the beads option too.

[nod]

We’ve done both in our builds Full fill is cheaper and easier T&G is better if done correctly Beads can be a nightmare and probably won’t be cost effective for an extension 

There are plenty of generic equivalent s to kingspan that won’t be subject to a minimum order 

[ETC]

Pump it….