So they put a hole in your duct, instead of strapping to the floor joist? I am no duct install expert, but I question that.

Interesting. Around here Pex would only be on supply lines and only installed by a plumber. PVC would be used for condensate drains. No way would a plumber screw into a duct. The pex doesn't appear to be strapped at frequent enough intervals.

That uninsulated duct looks to be in unconditioned area - certainly not code.

The hole in the duct is probably well sealed by the screw but it doesn't seem ideal.

Also .. and I'm no expert .. but it seems that they moved the duct from about 2 feet away to it's present position ( right to left ) and just used metal foil tape to cover the original hole .. I don't think that will stand up to the test of time

these are questions to ask hvac installer
plumber & possibly builder.

not enough info for us to make the call.

best of luck.

I bet there is a metal cover plate and then tape to hold it on.

Unless the tape is mastic tape it is worthless. The pex job is half donkeyed. If any of the screws in the sheetmetal of the duct holding the pex got stripped the expansion and contraction will eventually pull the screws out and after one pulls out the extra weight on the other will pull it. Make the installer fix it and screw it to the wood or someone else might be doing it later. A water leak could be involved in this mess also if not corrected as the metal clips wear on the pex which are probably for metal conduit.

Unless the tape is mastic tape it is worthless.
amen to that!

Lots of people here in British Columbia use mastic paint/paste, but lots use foil tape also. I didn't think there was any issue with durability, and it probably seals better than poorly applied mastic, I'd think.

I agree, the pex screwed to the duct is stupid and sloppy. HVAC people here do use PEX for in-floor heating etc, so why not radiators, I suppose.

What first caught MY eye, is the rim joists are uninsulated. Since they're so open and exposed, I'd be insulating them with ISOBOARD, the mylar faced stuff, or sprayfoam.

I was just assuming insulation wasn't done yet and this was new construction.

I hadn't thought about the pex being for hot water heat. I just figured radiator was a misspeak - does anyone actually still do radiators anymore? Seems like it would be forced air or radiant in floor. If the ducts are for a/c and this is Canada, how much does it really matter if there is a leak at the screw hole. Sloppy yes but when the annual a/c bill is $50 a little leak isn't crushing.

I find it amazing that there are four joists where the pex lines could be neatly and securely attached. Yet the installer choose to punch random holes into the brand new duct work.

You have to wonder what other corners were cut in this installation.

good catch allen.

second that the band/rim joist should be
air sealed and insulated.
spray foam or foam sheathing cut to
fit tightly & caulked to air seal.

according to code, paint on mastic
should be applied 'nickel thick'..
that's hard to do, but can be done.
lots of times I see just a thin thin coat
of mastic.
I can get 'dime thick' easily...doubling
that thickness takes more finesse. you
don't just get it right without trying.

the only tape I've found that doesn't fail
is hardcast brand #1402 mastic tape.
of course as with any tape, surfaces need
to be clean & dry for tape to adhere well.

best of luck.

Many thanks so far. I am pushing the builder for answers. Will let you know how this all turns out, your help is much appreciated.

Yes, this is an addition, and not yet insulated.....so that is up next. This previously exterior porch, will now be part of a family room.

And yes, we are keeping our existing radiators, adding a few more radiators in some rooms to keep costs down, and using underfloor Warmboard in most the the addition - family room, mudroom, and 3 bathrooms. The Warmboard was an extra $15K for the rest of the first floor, so we went with radiators. The pex is supplying the radiators.

You guys obviously have it all wrong. That is the new "duct to PEX" heat exchanger.

Hi ionized. I'm not sure that we have a heat exchanger at all. Can you explain more?

Sorry, Jennifer, that was a just a third-grade joke.

LOL Ionized. I am not so worried about the holes left behind after the screws pull out but the fact that after a few years and both lines are dangling having a water leak. In appearance it also just screams hack job.