Ducted systems should always be run inside conditioned space. I have yet to see a ducted system running outside conditioned spaces with adequate insulation for a given climate.
It’s easy enough to seal & insulate the crawl space or attic, even on a post-construction basis, and the benefits re: stack effect, humidity control, radon, etc are sufficient all by themselves. Never mind ending the US obsession with cold roof construction, soffit vents, and like relics from the 1940s.
For new homes, large ducted systems may be going the way of the dodo. Industry never addressed the obvious issues associated with contractors ignoring Manual D and regularly installing undersized ducts that impede performance and efficiency.
Large ducted systems do have one advantage and that is circulating fresh air around the house. If a house is tight and AC only operates in small zones, then fresh air needs to be piped and returned separately. Thankfully, those systems can be much smaller than traditional AC ducts.
Ducted systems should always be run inside conditioned space. I have yet to see a ducted system running outside conditioned spaces with adequate insulation for a given climate.
It’s easy enough to seal & insulate the crawl space or attic, even on a post-construction basis, and the benefits re: stack effect, humidity control, radon, etc are sufficient all by themselves. Never mind ending the US obsession with cold roof construction, soffit vents, and like relics from the 1940s.
For new homes, large ducted systems may be going the way of the dodo. Industry never addressed the obvious issues associated with contractors ignoring Manual D and regularly installing undersized ducts that impede performance and efficiency.
Large ducted systems do have one advantage and that is circulating fresh air around the house. If a house is tight and AC only operates in small zones, then fresh air needs to be piped and returned separately. Thankfully, those systems can be much smaller than traditional AC ducts.