Timber frame windows require more work...the glazier has to hammer out the old putty which at this stage is as hard as the timber frame itself, most glaziers will probably tell you they'd prefer to replace upvc type rather than timber framed..I had my sitting room window replaced about 4 months ago...from my old house and i got some alarming quotes...one was for nearly 200.00..most of them averaged between 130.000 and 175.000 but eventually I came across a glazier in Glasnevin who did it for 100.00 so it pays to shop around, i think the size of the window was approx 59 * 75 inches...it was the largest window in house.