Plastic internal window cill

[nstreet]

I want to remove my old tile window cill and replace with UPVC ones. Any advice on how to fit the new cill would be good.

 

[masona]

Did you mean window board as inside and not window cill as outside ?

 

[nstreet]

Correct, sorry if I got the terminology wrong!

 

[breezer]

so if you do mean the bit inside when my d g was done they used "a highly secure flexible, nonsolvent bonding agent" aka silicone.

seriously they siliconed it to existing inside bit, can't be bad if its used to hold fish tanks together

 

[masona]

Basically upvc windowboard are fitted the same way as wood.If the old windowboard is okay then you can use no-nail glue and bedded the upvc board onto it or take out the old windowboard and slot the new one into the groove of the window frame then maybe a batten on top of your wall with screw/rawlplug and fit windowboard on top with no-nail glue or window board strap tie into the wall.I have seen it done bedded with sand/cement but must put in self-tapper screw (be careful not to damaged the board on the top surface)under the windowboard for it to grip/bond into the sand/cement.
The only problem with upvc windowboards they do scratch very easily.

 

[nstreet]

Thanks for the replies. Do I need to rebate the walls either side to take the window board or can I just have a snug fit against the plaster?

 

[breezer]

up to you, ours are as you say "snug fit"

 

[masona]

Do I need to rebate the walls either side to take the window board ?

It will make it stronger if you do and prevents windowboard lifting.