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Get a roofer to pop along and cement it in for you. Well worth the charge from him (£80 - £100)?, than forking out for scaffold.
Probably take him longer to travel to the job than actually doing it.
What area are you?
How about this trick. I pass string out hole and put through flue at ground level and collar then pull up from inside until flue outside hole then put hand through and pull flue in. Let go of string (that also had weight on) in falls to floor outside. Pull up to boiler and clamp to boiler fill in from inside. No risk to installer from falls.
Most modern boiler flue can be fitted from the inside.
Drill a 127 mm hole, fit rubber cowl, push through hole and pull back and fix. Seal from the inside.
Personally I would be doing it of ladders, but then I dint mind working aloft
Reply to the thread, titled "working at height" which is posted in Gaining Plumbing Experience on Plumbers Forums.
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