Radiant floor install by contractor - questions

josieT

I'm a homeowner in process of getting a new radiant heating system put into an existing home. It will be floor heating for the first floor only and castray rads on the second. The contractor has been very nice but I want to double check a couple of things on the floor heating. Most of the first floor will have pex running under the wood floor. The picture below does not include reflectors which will be added soon. There is also a sunroom on a concrete slab where the pex will run on top and be enclosed in concrete. Pictures are shown. In my research, the sunroom concrete floor should have insulation under the piping and grid to prevent heat loss. My contractor indicating that he's never done it that way. Isn't it standard to put something insulating or reflective under the pex running on top of concrete?

I also included a picture of the subfloor pex piping and in-progress boiler/ heater install. Note the cover is off as the work isn't 100% complete. He is using Triangular a Challenger which cost abt 4k.

Any input on what is shown would be most gratefully appreciated. This is such a major job that it's a little nerve racking.

Josie

icesailor

Allison Krause has sings a song with a line in it: "You say it best, when you say nothing at all".

Bob Bona_4

Yes, there should be insulation under the slab, a vapor barrier on top would be good here. I use 2" rigid foam board. Is there a floor/threshold height issue? There should be a thermal break accomplished with insulation so the heat won't migrate to the ground (or old slab if I am seeing things correctly).

Yours is an old house. Balloon framed possibly. Tread carefully, outside air infiltration and floor thicknesses are high, the contractor must have a radiant design to see what the load is, and if the radiant can do the job without supplemental heat. At the very least you want heavy extruded aluminum plates under that floor, not the tin type, and even then, the contractor better have a grasp on if there will be enough output per square foot of floor, refer to the radiant design data.

I am also bothered by the slab tubing joint(s). Heaven forbid a leak develops after pour.

Short on time re the boiler pics. A lot going on, hard to see.

hot_rod

some good info on under slab here also

http://www.healthyheating.com/Radiant_heating_designs/insulating-underslabs.htm#.VFfXdSjNCS0

KC_Jones

Heat moves to cold always it's a law of thermodynamics. What do you think is going to be colder the inside of your house or all that cold dirt and concrete under the house? My guess is the cold dirt so your heat is going to want to go to whatever is colder, forget about all that heat rises stuff. Hot air (like the stuff that comes out of a lot of contractors mouths, couldn't resist) rises, but heat is a different animal. If your contractor does not understand this concept...maybe they need educated. Also I tend to notice things that indirectly relate to the topic at hand. In your pictures I notice all the times the very careless contractor tried to light your house on fire doing all that soldering. To me that shows the care they have for their craft and your house....or should I say lack of care. Did this contractor do a heat loss calculation for your house...and show you the numbers to show they had actually done the calculation? There should be numbers for every room you are having done, especially that sun room. I agree about that joint in the pex getting buried in concrete sounds like a recipe for disaster. Did he address water temps? Those old floors do not like high water temps at all new wood floors don't like it much either. I have installed 1000's of square feet of wood floors, they can be finicky. Just another homeowner, but those things jump out at me big time. If it was my house, I would either push him to make it better or find a better contractor. Educate yourself it is your best defense.

Ironman

Let's itemize a few things so it's easier to remember - for me, any way.

1. Did he use O2 barrier pex? This is a biggy.
2. As already asked: was a detailed heat loss calc. done? You got the results?
3. I doubt that the 12" o.c. spacing of the tubing in the sun room will provide sufficient heat.
4. The tubing should be sleeved where passing through the foundation wall.
5. How is the water temp to the slab being controlled? A thermostatic mixing valve (dumb valve) is not the correct method for a slab due to its high mass. It will cause it to over-heat in milder weather. You need a smart valve or variable speed injection mixing based upon outdoor reset.
6. I concur about the fittings in the slab and the need for extruded aluminum plates, not the staple up, aluminum foil type.
7. And the insulation under the slab is critical unless you're trying to heat your yard.
8. Does he have a digital combustion analyzer and know how to use it to set up the boiler?

Gordy

One other thing I'm wondering is how thick is that floor above the under floor radiant section? How many BTUs a SF will be needed to heat that space? Wood is about r .84 per inch depending on species. Plates,plates, extrude,omega!

As for the porch remember even r1 is 100% better than r 0 if there is a transition issue.

KC_Jones

Gordy said:

One other thing I'm wondering is how thick is that floor above the under floor radiant section? How many BTUs a SF will be needed to heat that space? Wood is about r .84 per inch depending on species. Plates,plates, extrude,omega!

As for the porch remember even r1 is 100% better than r 0 if there is a transition issue.

In those old houses that subfloor could be between 3/4" and 1" with an additional 3/4"-1" of finished floor on top...they are thick! My house doesn't have the subfloor, but the flooring alone is between 7/8" and 1" thick.

Gordy

Yeah that's a concern if you need some real btu's to heat the space, and not 160* SWT to get it.

On a side not the backer panel in the boiler room is all most done being painted black no?

rick in Alaska

The radiant section is also not piped right. Definitely going to want a pump out of the mixing valve to feed those loops. And I am not sure, but the radiant returns are in a weird spot, but I suppose could work. I am a little overworked right now to concentrate fully, so that part might be wrong.
I would absolutely make sure I had fire insurance on the house and you should really try and take away their weed burner. That workmanship on the soldering in regards to burning the wood is horrible. They need to work on their skills better and or get the right equipment.
Rick

KC_Jones

rick in Alaska said:

That workmanship on the soldering in regards to burning the wood is horrible. They need to work on their skills better and or get the right equipment.
Rick

They could also do some of the soldering away from the panel to avoid the situation altogether. There are so many ways to do this without burning the wood there really is zero excuse for doing it. Not to mention the huge risk of burning the house down. This contractor looks like they will be in and out all for profit and nothing on the back end when it doesn't work. If I was the OP I would surely NOT make final payment until the system is proven to work, no matter what is done going forward. This (on the surface) looks like a great example of buyer beware.

Rich_49

Pumping into the mixing valve and expansion tank is special . Pump must be on the mixed water side of tempering valve . Slab detail should include at a minimum a product like crete heat or Uponor Fast trak .
Make sure a room by room heat loss was done . Good luck , looks like you're gonna need it .

icesailor

"" This contractor looks like they will be in and out all for profit and nothing on the back end when it doesn't work. ""

The Contractor won't make a dime, even if he gets the final payment. Hackaroo's like that never make any money for profit. Here today, gone tomorrow. Like the profit they never made.

And the helpful person that tries to figure out all the wrong things won't make any money either.

There's never enough time for someone to do it right. But always time for someone else to do it over. If it can be done over.

Harvey Ramer

Stop all work right now, before it's to late.

If you think your contractor is a good fellow and willing to learn, send him here and we can help make sure you both end up happy. If he already knows it all and can't be helped, then you really need to find someone who is good with radiant flooring.

Another thing. You're not going to like this, but it is very likely that the price you received on the project is not high enough to give you the product that you are expecting.

Looking over those pics, there are quite a few mistakes that need to be addressed. Most of them have already been mentioned.

If you start telling the contractor that he needs to do this and that and the other thing, because you read it on the internet, it may end up in a bad situation for both of you. I would try my best to bring him on here and let us help both of you. I would start a new thread so nobody feels ridiculed.

Harvey

Docfletcher

Is there a permit? Is there supposed to be? What does the inspector have to say about the work and system? If you don't have a permit for the job please understand that permit are put in place to help protect you the homeowner.

Gordy

I totally agree with Harvey try to get him here if willing to be helped, and learn. This web site is hands down the most informative, and helpful on the Internet when it comes to hot water, steam heating, and a whole host of other comfort technology.

josieT

Thank you all for the comments. Much appreciated. The heating contractor has been in business for many years and is very reputable and done other jobs for my extended family and friends and city buildings as well. Heatloss calculations were done. The guy working for him to do the soldering didn't do the best job but the soldering itself is fine. (This has been an interesting learning for me - the folks who give the quotes who are licensed are not the ones that do the actual labor. They simply inspect the work and resolve issues. This was the case for all 5 companies who gave me quotes.)

The uponor fast track looks like the way to go on the floor so I will pursue that. He was concerned about concrete cracking with the barrier between concrete layers. The question on the mixing valve I will also pursue.

Required permits have been obtained and there will be a building inspection.

I will continue to monitor this closely. Again, the responses are greatly appreciated.

icesailor

When you take your car to the garage, you don't expect to get it back all covered with greasy handprints all over the seats and body. Good dealerships require fender protection and floor papers while techs wear nitrile gloves. And a clean car when you get it back. My motto has always been "A clean job is a happy job". As far as I know, no one ever hired me to make and leave a mess in their house. Most of us strive to leave a job cleaner and nicer than when we arrived.

No homeowner should be expected to accept charred wood when work was done. Even though I could solder well when I started plumbing over 50 years ago, about a week after I started, I slightly charred some wood near where I was soldering. The boss went ballistic. He made me get sand paper and sand out the black burn mark. You could still see it. That got my attention.

So many guys use "Flame throwers" for torches. They have this idea that hotter is better. Its not. It only has to be hot enough for the solder to properly flow. With flame thrower torches, the lower you turn down the flame, the hotter the end of the flame gets.

Some of us still swear by our "B" tanks with a #3 tip.

They have hoses for flame thrower torches but no one seems to use them.

Burned wood or paint is SO very tacky.

RobG

I agree that burned wood is tacky, However I do love my Turbo-Torch. With the proper tip it does just fine. I started out with a Prestolite and switched to Turbo about 30 years ago and never looked back.

Jack

Rob, granted I don't do it every day, but I use the Prestolite every chance I get. TT does a great job, but after years of standing in concrete rooms beating on empty steel pipe with a ball peen I'm all ready hard of hearing and the TT's should come with a Bose noise canceling head set. It all adds up over time. When we see each other at trade shows we stand around talking and mostly what ou hear is, "Huh"...Huh?

To the OP, Pex joints in the slab are a no-no for me especially where they can easily be avoided, as in you install.

RobG

Jack, I agree that TT's are loud however my hearing is just fine after 30 years of sweating joints and five years as a helicopter crew chief. My wife says that I have dog ears because I hear everything!

I agree, there is no reason to have a joint under the slab. Pex comes in 300 foot coils for a reason.

icesailor

RobG said:

I agree that burned wood is tacky, However I do love my Turbo-Torch. With the proper tip it does just fine. I started out with a Prestolite and switched to Turbo about 30 years ago and never looked back.

Well, I started with a B Tank at least 50 years ago, have numerous flame thrower hand torches for burning up spider webs, and using them along with the B Tank with the 25' hose, for soldering in those compromising positions where the insects and rodents hang out. I have a set or two of Turbo Acetylene gauges and tips when I need to use the heat wrench. But it is just way to easy to burn the paste into uselessness with the excess heat. And even those expensive heat shields (with the dire warnings on them about breathing their contents) either don't last long, or the heat still passes through them.

Like I said before, it's not how hot you get it, it's if you get it hot enough. And too hot is too much.

Ever soldered a closet supply on with the bell flange and the wall is papered with antique 100 year old wallpaper? I want to see you solder that with a flame thrower without charring the wallpaper. Paint scorches before you realize the paint is starting to melt. Let alone get it close enough to properly solder it.