Writing to Professor Wolfgang Feist, one of the founders of the Passivhaus standard, and asking him if he has dirt in his ductwork may not be typical behaviour. However, not only did the inquisitive Mark Siddall from LEAP elicit a response but Professor Feist did indeed take a look inside his mechanical ventilation system, concluding that it was as clean inside ten years on as it was on the day it was installed. Dirty ductwork is just one factor that could lead to poor ventilation and Mark Siddall was carrying out some of his own research.
There are lots of causes of poor ventilation regardless of whether you’re using a natural or mechanical ventilation strategy. The more airtight the house, the more important it becomes that these strategies have been well thought through and executed.
In fact, one of the main things I’ve learnt from this podcast on avoiding the risks of poor ventilation is that by the time we’re living in our houses all the hard work should be done! While we will always have total control over the ventilation and can, for example, open windows in a mechanically ventilated house whenever we want, the bits that matter are down to the professionals we hire. The design, installation and commissioning of mechanical systems all being critical steps.
So it’s back to that question of how do you hire the right team. Well Mark has some tips and he also shares his experience of the good and bad of ventilation systems.