I recently built some windows in sapele for my workshop/shed, and having built replacement softwood windows before (just for my home) just by scouring the metalwork sites (espagnolettes, hinge manufacturers etc) for design hints, I did some digging on the net to find out if there was more usefull info about.
I came across a 2009 copy of the Trada guide for wooden windows, which gave some usefull hints as to issue such as stormproofing, pressure channels and drip design, as well a host of other good stuff.
Can share it with you if interested.
Will post some pics sometime of what I eventually made - they turned out ok for me
I realise this is an old thread but I am looking to build my own windows and can't find much info regarding storm proofing, drainage etc. Any info from that trada guide would be appreciated.