How much of a gap to leave to fit door and frame?

[JoshRogan]

Just looking at doors - what size gap should I leave in my blockwork (100mm 440x210 DCBs) to fit a 838mm door and associated frame?

I guess a gap of 2 blocks would make sense, but that would leave me with around 100mm wider gap than the door itself - is that too much?

I've no idea what size door kits (frames) come in or whether it would be better to make the frame myself.

The door is for an entrance to a garage from the garden, so external door required.

Any links to door suppliers with dimension for frames etc appreciated. I've had a look at some, but any recommendations would be useful.

Thanks in advance

c
(PS. debated whether this should be a door&window posting or a building posting - apologies if I decided incorrectly!!)

 

[markthebuilder]

door frames thickness do vary from manufacturer to manufacturer so there isnt a def answer your best bet is to buy the frame and build blockwork up to it and fix frame to blockwork as you go with some fish tailed window ties , its a good idea to put a bit of wood across the frame in the middel so the weight of your blocks dont bend the frame

 

[Nige F]

If youre using a pvc-u door then you should be able to get dimensions from the supplier ...must be millions on Google

 

[noseall]

a standard door frame housing an 838mm door measures roughly 920mm, so if you were to leave a gap in the brickwork i would suggest 925mm or above.