self build help/warning for window and door openings

Robert Allen

Just thought id try to give some of you self builders the heads up /advice in relation to block work around windows and doors.

These days it is common practice to but an insulated slab on the inside of the window at the jamb and head to prevent/reduce cold bridging. It depends on the size of the slab you want but if the block layer left the inner leaf block shorter than the outer leaf you would be able to get a bigger insulated slab thus saving more heat with the added bonus of not covering up a large chunk of your window frame.

Also, if you are deciding to put stone on some walls make sure you have the correct detail for the window sections before you start. Organise with your Blockies/Stonemaseon & Engineer the best method. (It is hard to get a correct detail anywhere for this, there does not seem to be a standard detail and each Blocklayer, Stonemason and Engineer seems to have their own interpretation). Our Block layers were a little old school in relation to their methods and we made the mistake of presuming they knew what they were at. Im currently trying to solve this problem - where i am putting on stone the windows will be bolted to the outer leaf - not happy about this because of cold bridge issues. Make sure if you are putting on stone that they allow for the stone to be returned toward the cavity so you can put the window in a better position. Consider using a 450mm cill if you have large stone (220mm )facing.

Sorry about the long winded post - i am no expert so obviously seek out a professional who knows what they are at. I know there are different ways of doing things but Its just my experience of things that i would like to do differently on our build.

thanks and best of luck!!

B-D-P--

Thanks for info, Have you pics of your predicament?