Architecural modelling software

[andy <geek_show@dsl.pipex.com>]

I am looking for some architectural design modelling software that will 
enable one to design buildings and model the effects of lighting, wind, 
insulation values, etc.
Does anyone know of anything that can do this kind of job? I've searched 
on Sourceforge and google.com/linux but to no avail. Are there any 
architects here who could recommend a GNU/Linux Debian-friendly program?

Thanks muchly

--

"If they can get you asking the wrong questions, they don't have to worry about the answers." - Thomas Pynchon, "Gravity's Rainbow"