I have 2 uPVC (1200 x 600) windows (non openers) to be fitted into a wood construction out building. Window opening is fully constructed with appropriate lintols - so no problem there, and with a 5mm on all sides clearance.
The reveal is effectively solid wood - cavity closed at reveal.
My intended sequence is ...
# Fit cill ... pack to make it 5mm up off horizontal timber - screw fix in place with a couple of 6 x 100mm csk screws Q .. do I just pop these through inner (rear) chamber of cill, csk slightly into top face of cill
# run in bead of silicone against the cill upstand
# put frame in place against his wet silicone.
# fix frame to reveal with 6 x 120mm csk screw - frame packed to make sure screws do not 'bow' frame on tightening. Q .. do I screw direct through box section (appropriate pilot hole) .. or do I use a clearance hole in PVC box section to allow screw to pass though top section and bite onto steel box section - covering with a cap .... thought this may not be needed as screw heads are all hidden when glass is in place anyway.
# thinking of using 4 screws - 2 per side each 150mm in from top & bottom
# Also fix bottom of frame to cill with 5 x 40mm ... i.e. a fix to the cill rather than right through to wood frame.
Then fit glass, and then silcone frame to opening all round, inside & out.
Thinking of using standard 'Gold Screws' ... no need for Fraame fixings or Tapcon screws .. as all fixing is direct into wooden frame.
Does this sound correct ?