insulating hydronic mains y/n?

eluv8

I always recommend insulation, for the above mentioned reasons, but also something to think about is; the lines run through conditioned space but there is an incredible amount of draft that runs through the floor and walls if the holes in the top and bottom plates are not sealed the draft created will literally suck the heat right off the pipes and up into the attic or outside.

Unknown

to insulate or not...

I just had a discussion with a builder who didn't like the fact that I did not insulate two pairs of 3/4" pex mains going to radiant manifolds and how it was going to cost the customer a gross amount of energy over the years and adversely affect the system performance etc etc. The mains in question are traveling a total of approx 80ft. supply & return through interior walls & ceilings to their respective locations. I did a quick take in Hydronic Designer and although it doesn't list pex in the pipe heat loss calculator I came up with roughly 500 btuh of pipe loss. A negligible amount in my mind especially since it's all going into the interior of the house anyway. The builder was also upset that the pipes were touching in a couple of spots (or as he put it: "the whole way").

So, do you normally insulate pipes traveling through conditioned spaces? And how much heat would really be "short cycled" by supply & return lines in close proximity to each other?

Keith_8

Residential insulation

The short answer is yes, they should be insulated. Even tho the run is short and they are traveling thru a conditioned space the point is that we are delievering BTU's in a controled afshion. If we allow heat to be given up along the way we no longer have control.

It's been along time since I was in the residential marketplace so things may have changed. When we did HVAC work in homes pipe insulation was never a given. We used it on the MC Mansions but not a typical home.

Is your builder expecting it to be done for free or is he willing to pay for the pipe insulation? That is the real question. Is he is being consiences with your $ ?

Keith

Cosmo_3

this is always an issue after the fact

That is why I started quoting pipe insulation as an option on all my new installs.

Even most of the mcmansions I have seen don't have any pipe insulation, and usually nobody elects to install it because it's the pipe insulation, or the extra doo-hickies the tile man can do......

Of course EVERYONE that doesn't have it can simply blame us right?

CYA

Cosmo