If tradesman fails to use scaffolding, is the homeowner liable?
 

Basically, I need the gutters cleared on my roof (3 storey townhouse). I got quotes from various ppl. The cheapest I got was for 130gbp and I wanted to go ahead with that. I now found out that since the property is 3 storey's, to get that high, legislation requires tradesmen to put up scaffolding. The quote for 130gbp, came from roofers advertised on yell.com, but they do seem young. Not sure if they know what they are doing, and if not, if I will be liable.

THanks in advance.