[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: GSBN:Re: strawbale buildings in tropic climate

Regarding the above discussion I would like to comment on the following remark.

At 08:16 PM 8/26/04, you wrote:
Passive cooling should not be compromised by using high insulation
SB walls.

I think it is a misconception to only think that insulation works for
heating I am sure the writer of the remark which I have lost track of does
not mean it the way it now comes over.

Insulation is just as important for cooling maybe even more so when cooling
is required. If you want to go passive which I think you should strive to
do so in as many cases as possible it is still a good idea to use a
combination of mass and insulation. I do agree that the Panamese climate
zone is most probably one of the most difficult due to the almost constant
hot ambient night and day air temperatures. Although that said night
temperatures will always be lower the daytime. Besides there is a marked
difference between surfaces in direct sunlight and those in the shade,
insulation will help preventing this heat making its way in.

I am not sure what the specific local climate circumstances are. A low mass
little insulation well ventilated strategy will be the most appropriate if
regular wind is available specifically in the evening. The low mass little
insulation approach uses the least amount of resources and is the simplest
to implement. If there is little wind and relatively larger night daytime
ambient air temperature swings then the insulated mass approach works best.
To enable extra cooling wind towers and swamp coolers will increase
comfort. Specifically in the case of these relatively feeble 'cooling'
mechanisms the insulated mass approach will maximize their effect.

The above 2 approaches off course are born out by long existing traditional
practice all over the world. Again it all depends on local circumstances
including site location, available building materials and climate. The best
test case is to find out what is local best practice this will in most
cases be the best indicator.