+michael naude Thermodynamics is a very broad field; however as a Requirement on any Steep Sloped Roofing Assembly
NFA (Net Free Area for Attic Ventilation) is both a requirement of most Manufacturer's as well as Building Code.
I'm in Texas, where a balanced 1 to 300 for Attic Ventilation where possible is the nominal amount.
Where Architectural Constraints do not allow "Balanced NFA then the 1 to 150 rule is Used"*.
Now California understands the importance of Thermodynamics better than any US State I know of where even balanced areas have to be at the 1 to 150 Ratio.
How does thermodynamics apply to this and sustainability? By allowing a home or buildings attic space to breathe properly. The Cooler come in at the lowest elevation and allow the Warmer Air to Exit though the Highest Point possible.
Many older homes that once had "Wood Shake Roofs were designed without Soffits or Soffit Vents and when the Roofing Industry switched from Wood Shake installed over Strip Battens attached to the Rafters the Home Could breathe.
When Asphalt Composition Shingles became the norm, and after the IBC and IRC were adopted and indoctrinated Solid Sheathing was required for Asphalt Composition Assemblies.
At first Composition Shingles were attached over wood shakes,, before the IBC (Chapetr 15) and before the IRC (Chapter 9).
I remember once meeting with a Home Owners Association who wanted to Re Roof a 30 Building Town Home Community.
One of the First Questions they asked me was, "Why are we replacing a 10 year old Roof System?" My answer was, "You do not have any ventilation in your attics and the Asphalt Shingles are getting so hot during the Summer that they are Blistering and Aging Pre Maturely.
Next question, what can we do abut it? I said you have several option and I will provide examples with descriptions and then let you decide, along with recommending a much lighter color Shingle with a higher SRI.
Long story Short I redesigned the Ventilation Systems, so they were thermodynamically balanced. I won the award.
While the Project was about half way through on BOD Member called me and said, "Bill my AC is running is less than ever, and the 2nd floor is not getting near as hot". That was great news.
The Sustainability increase was estimated at close to 20% and greatly helped improve the ROI Period.
Since I am in Texas, T Boone Pickenspretty pretty much has most the Wind Generated Power already installed, working, and providing most of the States Renewable Energy to Green Energy Providers.
Do I understand the Importance of Thermodynamics? You bet. Do they make a difference? Big time. Unfortunately they are one of the most not understood aspects in the Roofing Industry, and very often they are not properly accounted for when Older Homes that once had Wood Shake Roofs are Re Roofed.
If you have more to offer on ways to improve Thermodynamics I would love to hear them.
Thanks for your time and response.
Respectfully