Ever seen the corners cut on bonus jobs? Some guys have to work that fast or get the sack they forget things. If your self employed you can do it in your own time and charge the customer for it. Most employees and BG contractors have to work to very strict time limits and so forget things.
That of course is a possible reason for the faults but it is not to be condoned all bonus and fixed price work on gas should be stopped.
Surly you cant be saying someone forgot to cut that flue you would of seen that when you pointed around it ( if it was done ) surprised a kid aint hung of it and snapped it yet. Or perhaps they use the flue instead of a washing line
jeez see so many of these in bradford. especially when it been a balanced flue and just the inside been bricked with thermal bricks cos the lazy sods cant be bothered to get ladders to brick up anything higher than groundfloor you just know it cowboys or diyers and it always a ravenheat or a heatline thats been installed
ye flue virtually upside down , no flue collar , just electricians tape , hadnt been patched up inside jus newspaper and some (and i mean some) silicon , tenant didnt have a clue , his kid sleeps in that room aswell , chronic installation.