Welcome! Here are the website rules, as well as some tips for using this forum.
If you've found help here, check back in to let us know how everything worked out.
It's a great way to thank those who helped you.
New design---piping questions
I'm still roughly sketching in my head how a retrofit hot water system would work in my 1950s house. Heat loss analysis per the Siegenthaler method gives 44K on design days. House is a raised ranch with 1800 SF on main floor, and below is half walk-out basement, and also a 750 SF unheated garage. Plan is to install 12 radiators on the main floor.
I understand the advantages of home run pipes in this situation, but because of the layout of the house, it would require running at least 10 pipes across the ceiling of the unheated garage. Even with insulation on the pipes, this seems like a lot of unwanted heat loss to the garage. So then would a parallel-direct return, utilizing just two (larger) pipes, make more sense for those radiators above the garage?
If so, should the rest of the radiators, those above the heated basement, also be direct return, or would it be better to home run them? It seems to me there might be an advantage, when it comes to balancing, to have the whole system piped the same.