The wayward wind

Did you know that around a third of all the heat lost in an un-insulated home is through the walls and that just by insulating your cavity walls you can reduce heat loss and save money on your fuel bills?

Needless to say, as soon as I found out, I was quick to call in the folks from the local cavity wall insulation company. After all, not only would the insulation help me heat my home more efficiently, using less energy would also reduce the carbon-dioxide emissions from my gas boiler. And, being a bit of an environmentalist, I liked the idea of doing my bit to slow down the effects of climate change.

Before performing the work, a chap turned up to conduct a survey of the house. While he was quick to re-iterate all of the financial and environmental benefits that the work would bring, he also told me that, as part of new regulations, it would be necessary for his team to fit a vent through the cavity wall before performing the insulation – all because I had an open fireplace in my living room.

The vent, he explained, was necessary to eliminate any risk of a build-up of carbon monoxide, which could possibly become a problem due to insufficient airflow.

A few days later, the cavity wall folks turned up in a rather large vehicle and duly set to work. First off they created a large hole in the wall with an auger and installed the vent, after which they drilled smaller holes through which they filled the cavity walls, injecting each hole in turn, starting at the bottom and working their way up. It was a highly efficient process and took the two gentlemen just two hours to complete.

I’m sure you can imagine how much I was looking forward to living in a much warmer house after the work had been done. But when the winter winds started to blow, the effect of the new vent that had been installed in the living room became apparent – the bitterly cold wind was howling in at an unprecedented rate. It couldn’t have been any worse if I had left a window in the room wide open.

Clearly, the new vent was doing little to lower my fuel bills, so against the advice of the insulation company, who insisted that the vent be open at all times, I found a large piece of cardboard, which I used to cover it up, preventing any more of the cold air from racing around the room.

I’m pleased to report that the house is now a lot cosier than it was before. And the energy savings that I have made have been considerable.

However, the logic of installing an open vent as part of an energy-saving process still troubles me. Indeed, it seems completely contradictory – the equivalent of designing a circuit that can run at 3GHz and then throttling it back to half speed before shipping it to a customer. I ask you, what engineer in his right mind would see the logic of that?

Dave Wilson
Editor, Electronicstalk

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