New ICF House and need someone to assist with Radiant heat design

KLaugh

After spending several hours studying the post on this site, I have come to the conclusion that there is a lot of mis-information on the internet. I am in the process of building a new house with ICF blocks. I am going to use 8" concrete for the basement and 6" walls for the floor level. I am planning on the basement slab to have insulation under and tubing in the slab. The floor level will have the tubing mounted to the floor and overlayed with light concrete. The basement will be unfinished for some period of time so will probably not need to be heated too warm. I will be using propane for the heat source.

I am not opposed to paying someone to do a design that will in my situation. I live in Northern Colorado where it does get pretty cold. I am very capable of doing all of the work myself. Just need the plans or guidance. The closest company that I can find is over 75 miles away.

KLaugh

Here is the layout of the main floor. The basement would basically be the same with no walls and 3) 3'x'4 egress windows.

Ironman

Have you done an accurate heat loss calc like a Manual J?

KLaugh

Ironman said:

Have you done an accurate heat loss calc like a Manual J?

What is a manual J? New term for me. I have attemped to do one without any success. I have read one thread on here that the calculations on ICF do not calculate well.

Here is the link. My design is very close. https://forum.heatinghelp.com/discussion/164957/figuring-heatloss-on-a-super-tight-home

Tim Potter

A great source of info would be @Mark Eatherton in Denver, contact him through this site, he is a wealth if info.

You will love radiant done right!

Tim

Ironman

A Manal J is the approved method of heat loss/gain calculation. It's published by the Air Conditioning Contractors of America (ACCA). There are several programs that calculated based on it.

SlantFin has a free app that you can download. If ICF construction data is not in it, just use something that's close to it with a similar R value.

nibs

Will leave the radiant heating comments to the experts, will say that ICF is a really good way to build. If I was starting now on my house build, it would be all ICF right up to the roof.

Rich_49

If you'd like give us a call . This attachment is from an ICF home in Ann Arbor , Michigan .

KLaugh

@Ironman I did download the slantfin software and will be doing some calculating in the next few days. Thank you to everyone for the excellent repies.

Gordy

Rich Mcgrath is one you wont be sorry to be on point for your project design.

hot_rod

No reason your designer needs to be in Colorado, Rich could be your guy.

Ironman

You won't get any better than Rich to design it for you.

DZoro

Love those houses, Don't forget the air-air exchanger. Super efficient and tight. Will be interesting to see your load calcs.

hot_rod

Don't expect warm floors necessarily in a super insulated with low, low heat loads. I did several years ago and the floors didn't run much, appliance and lighting kept the home warm.

Mrs homeowner expected the slabs to be warm all the time in the heating season, she was a bit disappointed.

If I were to do another I'd consider panel rads, radiant floor in baths maybe kitchen.

https://www.pmmag.com/articles/83903-heating-a-thermos-bottle-house-br-john-siegenthaler

DZoro

True to that @hot rod I have done with success staple up zoned on main level. Basement radiant, but yes the HO's say the basement zones rarely come on. Can keep low water temps with very good efficiencies.

KLaugh

@Hotrod The link you shared is very insightful. This heating project is in the vary early stages so can be changed. Is there a better alternative to in floor radiant that I should look at.

Rich_49

KLaugh said:

@Hotrod The link you shared is very insightful. This heating project is in the vary early stages so can be changed. Is there a better alternative to in floor radiant that I should look at.

Radiant ceilings are a very good option . Floors will be within a couple degrees of what they'd be if they were tubed . Panel radiators work well too , but if you want true radiant comfort you'll only get it with a radiant solution . While keeping Tair good , it is still not MRT comfort and you will use higher water temps .


https://www.pmmag.com/articles/96488-radiant-ceilings-are-a-great-option-in-many-systems

hot_rod

KLaugh said:

@Hotrod The link you shared is very insightful. This heating project is in the vary early stages so can be changed. Is there a better alternative to in floor radiant that I should look at.

It will come down to personal preference, panel rads heat mainly by radiation also, so in front of them you get that same radiant comfort. With a radiant ceiling you get that effect everywhere.

I like panel rads in bedrooms as you can set them back and they speed up quickly for keeping the bedroom cool at night, warm when you get up and setback again during the day. Each radiator can have a thermostatic valve and be temperature controlled. Most homes and buildings across the pond are heated with panel radiators and there are hundreds of styles and choices.

Radiant slabs are slow responders, so if you see wide temperature swings, of have a lot of passive gain from south windows, they can be hard to manage, and keep a comfortable space.

You can mix and match, radiant ceilings in living areas, radiant floors in tile showers and bathrooms, panels rads elsewhere. That is the beauty of hydronic heating, many controllable options.

In a tight home you will want some air change and movement with a HVR or something to allow fresh air in. A warm stale home, not so comfortable. Humidity control is crucial in your area also, very dry in winter.

KLaugh

@Hotrod I do kind of like the idea of panel radiators in the bedrooms. The turn down/up option is nice. Would this style work well in a basement also?
Now if I do radiant tubing in the living areas and concentrate the tubing in the walking area's and less in the other areas to get the complete coverage would that make the walking areas warmer? Am i thinking wrong?
The quick heat loss calculations I have done are around 27,000 BTU/hr. These are pretty rough but 2 online calculators came up with the same thing.

hot_rod

Exactly right, a clever designer could manipulate to tubing to provide just the correct amount of output in the ideal areas. Load the tube in the areas where you congregate. Or whatever you call it

Typically we load tube around windows and exterior walls, with a low load system like yours, assuming it is a low load home, pull the tubing in a couple feet perhaps. Nobody stands around by the windows all day. Put the tube where you want to "feel" the radiant warmth.

Here are a few of the custom radiators I have built. The dog is 400 lbs of concrete with CSST tube inside connected to the bathroom loop, a large towel bar that I welded also, about 4x2"
I also have tube in some concrete counter tops in the bathroom.

The "J Garcia" bus is an old solar absorber plate from a Revere collected 1978 vintage. Reach out of bed and crank up the TRV "hitch" to start the warm up.

hot_rod

You'd be a fool not to have a copper hydronic bed frame in a home like that, the pantry radiator is also on the radiant loop

KLaugh

@Hotrod Those are some really cool ideas. Not sure how the bed frame is going to work with someone that likes to rearrange furniture often.

KLaugh

So I have done heat loss calcs on 3 different calculators. It looks like the Kitchen is 3576 BTUH, Living Room is 2815 BTUH, Master 3057 BTUH, BR2 2191 BTUH, Utility 669 BTUH, and Basement 14263 BTUH. Comes up to 26,5701 Total. Does this sound right?

Zman

That looks pretty close...

DZoro

That is pretty close, there is plenty of room in that number. I wouldn't be surprised if you well below those numbers in real life. So if you design on them and don't go higher you should be in good shape.
Use good floor/air sensing thermostats, Outdoor Reset controls, Good modulating boiler system from a reputable local contractor who can set it up properly.
Heat pump system works nicely in combination with radiant also. I like to use the heat pumps in the fall and spring seasons where radiant doesn't play so well in 50* temp swings.

KLaugh

So would a Lochinvar CDN040 boiler be a good choice for this system? It doesn't look like there are many boilers that are that small. Are there other options that would be worth looking at?

kcopp

I believe that unit has been discontinued. Lots of good options.
I would use a unit that your installer is most familiar with.

DZoro

Lochinvar now has the Noble version in Boiler only, and in the Combi. Both would be excellent choices.

Zman

I think I would be looking at the newer WHB055. It will actually turn down lower than the CDN040 with a little more high end for making DHW. I like the firetube design better as well, it uses less circulator energy and even modulates the boiler circ to give optimal delta T across the boiler.

Zman

Keep in mind, you need to derate the boiler ~2% per thousand above sea level. With Lochinvar, be sure to order the high altitude model. The local supply houses will know this, online retailers will not.

KLaugh

@Zman Good call on the derating. I would have probably missed that. Utica has a nice little unit also. SSC050. There are a couple more that I am researching. The CDN040 was a good cost option. Looks like it was just discontinued in January.

I can see how people wind up with a tankless water heater for this type of application. There are many in that range that market themselves as a hot water boiler.

Zman

If the CDN is a screaming deal, go for it!
The nice thing about Lochinvar in Colorado is the availability of parts....