Closing Cavity above window

[vfrdave]

Block build house 100mm outside, 150mm cavity and 215mm inside skin (for wind loading)

 

Using 2 concrete heads above the window, what is the best method of closing the cavity above the window.  Builder has suggested that I will need 3 heads:- one external skin, one on internal and a boot head and some insulation to close the cavity.

 

There has to be a way to close it using 2 heads and something, what should that something be?

 

Thanks in advance.

[Declan52]

Using a boot head is the easiest method.

Your windows if going for 3g will be 90mm+ so if you use a boot head it will cover what's left.

You would be using 2 heads on the internal wall anyway to fully carry what's above so it won't be much extra to use a standard head and a boot head.

Edited March 20, 2017 by Declan52

[Oz07]

Why have you discounted a standard cavity closer? 

[vfrdave]

I haven't just asking for suitable/advisable options. Any comment @Declan52 regarding a cavity closer

[Declan52]

Don't need one if you use a bootleg head. I remember pricing them up and the cavity closers weren't cheap. 

Plus you then have to use plasterboard on the underside to cover the closer which is more work. 

Price the two options up but it's no extra work as the brickies are already lifting 2 heads just means 1 with the boot is slightly heavier.