Fitting UPVC window frane to catnic lintel

[davphi338]

Hi,

Are there any issues I should be aware of when fitting the top of a UPVC window frame to a catnic lintel. The lintel is in a single storey extension so there is no brickwork above the lintel it is boxed in with soffit and facia. I am going to screw the frame on the sides with frame fixings and then use silicon sealent on the top where the frame meets the lintel. Is this sufficient.

Thanks

 

[freddyuk]

I would use expanding foam to make a "fixing" to the lintel and fill any gap. Just using silicone would not provide any form of support to stop the unit moving in use.