Hi, Has anyone installed a heat recovery unit for the shower / wet room? Just wondered if it's worth the effort / risk of failure vs marginal waste heat recovery? I was looking at the Passive House component database and they had a section on it, this one caught my eye as it was the best performing (just listed as an example only): http://www.showersave.com/qb1-range/ I might look at including something similar in my build, a horizontal one for the wet room and the vertical one fo