Yesterday I discussed my DIY harvesting of the heat in the roof cavity. I have now come across a commercial system that does just that – Ventis. And they appear to be doing it with style. Well, they have George Gregan backing it, so it must be good.

Their system appears to be less complicated than mine – they take the air from the roof cavity and pump it into the house. So that air up there that is 30°+ in winter is brought down where it can do some good.

In my defence, there is no way that I would be taking the air from my roof cavity and bringing it into my house. I’m not that stupid (still trying to work out how stupid I actually am). But Ventis pass it through the proper filters and end up with incredibly clean air. I will probably talk more about this tomorrow.

So for the price of a light globe (I suspect they mean 100w, not a 20w power saver) they are heating the house in winter.

In summer they are just a lot more efficient at pumping the hot air out of the roof cavity. So my DIY option isn’t that far off the mark. I felt good about that.

The price tag is expensive if you compare it with a split air-conditioner, but is cheap if compared with a ducted system. Running costs, however, is no comparison. The reality is that this won’t replace the heating and cooling systems, it will just mean they will spend more of their time idle. And given that some of these heating and cooling systems are costing many dollars a day to run, leaving them idle is a very good thing.

I just think it sounds like a great idea (which I thought of first, of course) and it’s great to see someone doing it.