June 24, 2014
Correctly designed earth houses out perform light weight on many levels. Here is another example.
A recent study in Australia and the US has found a link between obesity and diabetes with house temperatures. They tested people sleeping in different controlled room temperatures. The temperature influences the amount of brown “healthy” fat the respondants grew.
Dr Lee, from the Gavan Institute said “…,brown fat cells, I kind of see them as generators or powerhouses. Instead of storing energy brown fat cells actually burn energy and because of that, animals with lots of brown fat are actually protected from diabetes, obesity, and a full range of metabolic disorders.”
“I think the exciting thing with brown fat is it’s in a territory that we have not explored before and it opens new directions,” “Obesity is a global health issue, and most strategies in counteracting obesity involve reducing food intake or increasing exercise which can be difficult to sustain and ineffective in the long-run.”
The study reported house temperatures have risen on average 3 degrees in 20 years! Earth houses with higher thermal mass usually requiring more heating energy than cooling energy, I feel the current Australian system of NatHERs unfairly disadvantages high mass earth houses because they are slow moving. Earth houses with slow moving temperatures have a consistent temperature because of thermal mass.
The thermal lag means they are up to 12 hours slower to react to temperature changes. Light weight houses are easy to heat as you only have the air to heat, but heat in the air is easily lost. This means if the house drops below the perceived comfort zone you need to heat the entire thermal mass. If the temperature was only going below that comfort zone for a hour or two, you would need to add loads of energy to the whole house and thermal mass to increase the internal air temperature by 1%. Read about the study here.