Why, a plumber would be ashamed to take as long as that over a job! Another combi boiler benefit is that it can generally save you money on installation time and costs, since no tank in the roof space means less pipe work and a shorter installation time. Feel free to share on social media, the more people the that know about the benefits the better – you never know you may save family and friends some money! Search for a planning application. We used kil block on the bathroom waste.