Radiant Floor Heat Highly Inefficient, I think I messed up somewhere?
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But not everyone shops based on ROI. I don’t. Sell high end hydronics on the features and benefits. Many people will spend more for a nicer, more comfortable, up sell system.
A2WHP come to mind🤔
I recall somewhere around 2 million Alphas have rolled of the Fresno manufacturing line. That is one of at least. 4 players in the residential sixe circs. Soon PSC circs will no longer be manufactured. I think a lot more ECM circs out there than you realize.
You might be right about few ECM running. 37W, more are probably running around 17- 25 W.
We tend to see older, often problematic hydronics here on HH.
Follow IG or FB, trade mags, and see the younger generation of installers/ designers full in with ECM circs, pro press, mod cons, A2WHPs, HPWHs.
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream1 -
Just a final note about spray foam, aside from the R value discussion. For me, the main driving factor, aside from the insulating factor, was actually my desire to build a conditioned attic space, so I didn't have too many options that would fit the bill aside from spray foam.
Living in Calgary, Alberta, we have what are called locally the Chinook winds, which can sway temperature from -30C (-22F) to +15C (59F) in a day, and with a traditional vented attic and hole riddled "vapor barrier", moisture will escape into the attic and accumulate on the underside of the roof deck over prolonged deep freezes. Chinook winds will arrive carrying very warm air, and within a day will start melting the frost that has accumulated, which leads to attic rain. Can read about it in our local Calgary news here:
Now you have what basically looks like a shower happening in your attic, all over your blown-in insulation, your vapor barrier can start leaking wherever they didn't make a good taped joint or a hole is present, and next thing you know you have nice brown spots on your drywall ceilings. Only way to avoid that is to basically have very low humidity inside the house, which isn't very comfortable. It's a massive pain in the ****, so when time came to look at alternate build systems, conditioned attic with insulation to the underside of the roof deck seemed like a good option, and that is what we did here. It also allowed me to very easily run all my HVAC work in the attic without having to insulate it, there is no poly up there around all the lights/fans ect, so it made that very easy to do, especially since I was doing all that work myself. Additional benefits that I didn't consider initially and learned about later were to do with it's ability to add structural strength to the structure, since it basically glues everything together and makes things more rigid. I have actually also opted to spray the bottom of my staircase, as its supposed to prevent them from ever creaking in the future. We get crazy winds out where I live, and the house feels super solid at all times. My old place would shake with these kind of winds and make creaking sounds…not very comforting.
As @hot_rod mentioned, not everyone shops based on ROI or price, some people shop simply on what they want and what they think is a superior product. I'm a bit weird, I have problem paying for small things that are expensive, but have no problem spending the money when it comes to quality or large good purchases, think it's a disease :D
Anyways, thanks everyone for the help. I have made the following changes in my system, and we will see how it goes:
- Increased flow to all my zones. They never fire up all at once, and even if they do, I should be fine with this increased flow. This has already made a difference in floor temp distribution.
- Increased max floor temp to 26c
- Reduced boiler to manual setting in the 104C-140C range based on outdoor reset. It's the lowest it will go with outdoor reset, so we will try to go with that for now.
- Set my HRV to 20/40 mode, only runs for 20 min every hour instead of constant.
- Lowered garage temp to 10C for now (from 15C)
Thanks everyone again for your suggestions, I will come back in a few months and report if I notice any difference in not just the bills, but in how everything is running. So far….I feel like the boiler is running less..but that could just be in my head.
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Sounds awesome. Nice House! If it were my place I would only run the HRV during the warmest ~12hrs of day, and only intermittently through that time. Home air quality monitors are fairly inexpensive, you may be interested in monitoring the effect.
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What you have is called a "cathedral ceiling." They are tricky, many builders don't know how to get the details right. Spray foam is one approach that works, there are others, this article lays out five approaches:
There's no reason not to have code-appropriate levels of insulation just because it's a cathedral ceiling, especially in new construction and especially in a climate like Calgary.
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There are also a lot cheaper ways to add R value to new building assemblies than spray foam. I like to say if you are using spray foam in a new build, somebody didn't do their design homework, spending good money for not much gain.
You might find a cheaper way to stop the air leakage in a new building but I seriously doubt that you can do anywhere near the complete and total elimination of infiltration without the spray foam. Trying to substitute it for strictly R value is what you are referring to as spending good money for not much gain. All your gain comes with the first 1/2" to stop the infiltration.
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There are lots of people building houses with very low infiltration numbers without using spray foam. Go to a performance building-oriented site like GreenBuildingAdvisor.com, people are routinely getting sub 1.0 ACH50 numbers just by taping the sheathing and paying attention to details.
I do agree that a thin layer of foam gives all the air-sealing benefits. There is a technique called 'flash and batt' where you lay down a thin layer of foam and then fill the rest of the cavity with batt insulation. Batt is so much cheaper than spray foam for the same insulation value that you get a lot more for your money.
Spray foam is also useful if you have existing construction with irregular surface, like, for example, a rubble foundation. But in new construction you should be able to design out those situations.
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I'd sure like to know how to "pay attention" to details like soffits or the gable end without spray foam…………..you could spend the rest of your life "paying attention". Without it, you'll use hours of time and tons of caulk………….and still probably not quite get it.
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The answer doesn't lead itself to quick message-board response. If you're really interested in the answer, I recommend this book:
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Kaos seems to be forgetting a little thing called thermal bridging, which does have "units" and can easily be calculated to convert R value to effective R value.
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Spray foam does nothing to reduce thermal bridging.
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Nobody suggested that it did….
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I believe the term you are looking for is assembly R value. You can calculate it by hand or use handy on-line calculators likes this:
Assembly R value is still R value and it has the same units as any insulation. It takes into account the effects of thermal bridging as well as the bit of R value you gain from sheathing/siding/drywall and air films.
Interesting tidbit is that if you add spray foam between studs, despite the impressive center of wall R value, the assembly R value doesn't change much. Basically wasting expensive insulation for not much gain.
@LRCCBJ Air tight construction is not that hard once you figure out some of the details. You can get impressively low infiltration with good design and a couple rolls of fancy tape. You don't even need much if any caulk.
It is also very easy to build a leaky all spray foam house. I have seen places that don't even meet code min leakage even with full spray foam. If you look at a typical new build, 80% of the spray foam is applied to sheet goods which don't actually leak, so even a flash coat is not buying all that much.
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hard to blame an improperly spray foamed job against the product?
When I walk around a spray foamed house I see foam oozing out of every sheathing seam
Now if you use ZIP sheathing and their seam tape, that makes for a tight envelope, I might skip the spray foam layer on that type of system
I would still foam around windows and doors with the correct product. Jamming fiberglass into those gaps isn’t a great detail
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream
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There is nothing wrong with canned foam. Good stuff and you'll use a case or two to seal things up.
One issue with foam is it doesn't adhere to vinyl so as the building moves overtime it will separate from window and you'll get small leaks. Not huge, but you can feel the cold draft there, so it is always better to rely on something other than just canned foam for sealing. A good tape is usually the best backup.
You can also go spray foam free. Tape to window and install into the rough opening. The tape will slowly expand and seal the gap.
https://proclima.com/products/connections/window-sealing/contega-fiden-exo
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spray foam sure sticks to PVC pipe and windows. It sticks to the seam tapes also. Maybe there are some PP vinyls that it doesn’t stick to? Although I have seen some jobs where the spray foam pulls away from the wood framing. My insulator claims that is caused by improper mix or application?
A thin layer of spray foam around the wood, then some of those foam rods to fill the void is another option.
It’s the expansion component of the foam that finds and fills in the gaps, the tapes just put a thin layer over the seams and cracks. But the wrong foam can push window and door frames out of plumb.
Around the desert west the custom builders go with ZIP system, track home builders use waferboard with various house wraps, often with the lumber companies name on the wrap for advertising
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream0 -
Maybe it is the release agent on the PVC extrusion, been there and had to fix it. Spray foam does seem to stick almost everything else though, fiberglass or wood windows are not an issue.
ZIP does get the sheathing sealed up so definitely a good step forward but does not guarantee an air tight house. You sill have some transitions to deal with like foundation to sheathing, sheathing to ceiling and any interior partitions that might interrupt these. Any 1/2 story structure, dormers, pop outs and attached garages with bonus rooms can also create a lot of air barrier transition challenges. All these can be dealt with but does require a bit of design up front. The good news is none of it requires spray foam and when designed in, the additional cost is pretty minimal. Probably the cheapest energy efficiency and comfort improvements one can make.
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