Anyone have any experience installing or living with a Space Pak residential air conditioning system?

A house that I’m considering buying has no central ac; just portable window ac units. For heat, there’s a boiler in the basement that circulates hot water.

When installed, Space Pak gives a house central air conditioning. It uses smaller diameter flexible ducts installed in the attic instead of sheet metal duct work. Because the diameter of the flexible ducts is smaller than sheet metal ducts, the duct air flows at a higher velocity. This is about all I know about Space Pak. I never heard of Space Pak until recently. What do you think of it compared to a regular forced air unit that uses common duct work for both heated furnace air and cooled air? Is it expensive to install?

I believe Brenda next door has that system in her house. I've seen them but I don't know much about them other than they're used for historic homes and such where the don't want to run standard ductwork or install standard registers.

I do know they're expensive, and in most houses it will be cheaper to install a standard forced air system.

Have you considered a multi-zone "mini-split" system? Popular in Europe and Asia, and gaining in popularity here, they can also be installed without too much plaster demolition.

Back in the early 1990s, my mom installed a Space Pak type of system in her 1950s split level in suburban Chicago. The house had hot water heat (boiler), so there were no ducts.

It was in a subdivision of houses that were pretty much identical to hers and there were a couple of HVAC companies that had the installation down to a science because they knew how the homes were constructed and where to run the ducts.

I never lived there, and my mom sold the house four or five years after she installed the A/C, but when I was there during the summer to visit and the A/C was on, it seemed to do a great job. One of the advantages is that the ducts were installed in the ceiling, so the cold air came down, rather than coming out of ducts down on the floor like regular combined systems do.

The mini-split systems weren't available back then, but I'd definitely look into those, too.