30 yrs ago i read a POPULAR SCIENCE article wherein a WHITE ROOF was specified for a woodshed. i cant remember any other specs but the white roof kicked my head!any possible reasons for such? i assume the white roof will be cooler than a black roof & the wood wants to dry
thanx
oh the glare 
my eyes hurt
my eyes hurt
I just pray it had nothing to do with racial segregation. 
I learnt this one in year 8 science class if I remember correctly. Most people know that dark colours absorb more radiative energy than lighter colours. What people often don't consider is that dark colours transmit heat by radiation better than light colours. Your white roof is to minimise heat loss to the atmosphere by radiative effects. A similar argument goes for why the back of a refrigerator is black.
QUOTE (prometheus+Feb 10 2010, 10:50 PM)
I learnt this one in year 8 science class if I remember correctly. Most people know that dark colours absorb more radiative energy than lighter colours. What people often don't consider is that dark colours transmit heat by radiation better than light colours. Your white roof is to minimise heat loss to the atmosphere by radiative effects. A similar argument goes for why the back of a refrigerator is black.
The back of a refrigerator's color has little bearing on the thermal function of the unit.
You are correct about minimizing excess radiated heat to a dry wood pile. Metal roofs are typically insulated inside, with a moisture barrier.
White reflects heat away from the building.
The back of a refrigerator's color has little bearing on the thermal function of the unit.
You are correct about minimizing excess radiated heat to a dry wood pile. Metal roofs are typically insulated inside, with a moisture barrier.
White reflects heat away from the building.
QUOTE (prometheus+Feb 10 2010, 05:50 PM)
I learnt this one in year 8 science class if I remember correctly. Most people know that dark colours absorb more radiative energy than lighter colours. What people often don't consider is that dark colours transmit heat by radiation better than light colours. Your white roof is to minimise heat loss to the atmosphere by radiative effects. A similar argument goes for why the back of a refrigerator is black.
thanx! makes sense & has implications such as maybe i should paint the wall in back of my fridge coils black. also an overcooled woodpile might be apt to collect the morning dew better
thanx! makes sense & has implications such as maybe i should paint the wall in back of my fridge coils black. also an overcooled woodpile might be apt to collect the morning dew better
How significant an effect might roof color be considering wood is stacked with airspaces? how might overnight weather factors affect the radiATIONAL cooling of a black roof?
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