Screwing into catnic lintel

[davphi338]

Hi,

What would be the best fixing to use for installing a new upvc window that has to be secured directly into a catnic lintel.

Thanks for any advice

 

[^woody^]

Expanding foam or a silicone adhesive, rather than a screw

 

[davphi338]

Thanks for the reply,

I take it just normal expandable foam would be OK with frame fixings used on the other three sides ?

 

[dextrous]

Just the two vertical sides will suffice - you don't want to give water any "excuse" to work down the base of the window.