After two years we noticed water stains in the living ceiling. We got a plumber to have a look and he had found the builders (Redrow) had nailed the skirting board under the combi-boiler into a pipe.
We contacted Redrow for help, they replied after 2 months to tell us they will not take responsibility for this.
The build quality isn't very good, they also are very difficult to get snags fixed with.