What passes for underfloor heating- Thoughts Welcome

Brad White_9

My friend Sari has an 1850's house in western MA. Her local contractor was asked to install radiant floor heat, part of which was to remove a cast iron radiator from the kitchen. (System is hot water with cast iron radiators.)

After having it described to me (not having seen it in person), as suspected it is fin-tube hung below the joists in a crawlspace. No enclosure below, just open to the crawlspace and contiguous basement.

(After this discussion, Sari remembered what I did for a living and would gladly have advised pre-contractor... but this is where we are....)

Naturally my concern is to preserve her comfort and operability and get any corrections made before the heating system is in full force.

So far my comments have been:

1) Asked if separately controlled both by circulator and boiler demand and/or by reset schedule. (Cast Iron versus Cu/Al fintube and all that.)

2) What guarantee for temperature would be expected; what is the performance criteria? Was a heat loss even done? I was told "yes" but have not seen it.

3) Naturally noted that there is no under-insulation nor contact with the floor, that the crawlspace would have to be heated to 120 degrees to effect a kitchen floor temperature in the radiant range.

Short list but the essence of it. I was also told that the contractor is re-thinking the "no radiator needed" tack and is suggesting some supplemental radiation now above the floor.

The photos show a finished installation; there was no mention of under-enclosure nor insulation. WYSISYG. Note also the charring on the plastic hangers in Underfloor 2.

Comments welcome, not just to bash the installer (who may not know better) but to elevate his practice. Also if any solutions short of a rip-out exist. Thus far I can only suggest insulating the crawlspace on the bottom five sides and close it off as a hot plenum. Weak, I know....

Ken_40

Unless the home is located in...

Miami Florida, the output might be on the order of 2-5 BTU's/s.f. - and unless the water is delivered at 180+, proide even less.

The only way to get anything more tha 5 BTU's / s.f., would be to install 2" reflective surface (facing up) uder the floor joists, and then, maybe 10 BTU's / s.f. might be realized.

Mark_46

Hi Brad

I certainly understand what your saying with regard to the contractor (most likely) not knowing better. But what I want to add is from a customer / contract persepctive.

If asked to install radiant floor heating as you described, this is not it by any industry standard. As a result the contract/request has not been properly fulfilled. In my opinion, at minimum, the contractor is obligated to correct to accepted industry standards at no extra cost (if owner wants to stay in a binding contract with them - I wouldn't) or refund the full amount.

Unknown

the space

Holy bat cave, its gonna get mighty warm in the crawlspace... It'll warm the naked feet but the living space? Doubt it, I would try to box it in with relfecing side inward. And install cast iron base board to regain the comfort of old radiator...

John Ruhnke

That contractor is a discrace to the trades.....

Brad,

That heating system is a crawl space convection heating system not a radiant heating system. Most of the btu's will heat the crawl space. Very few btu's will go up through the floor. Obviously this contractor didn't follow any established set of rules or practices. This system will cost a lot in fuel bills and the rooms will be cold. The first step is to hire a competent radiant heating contractor. I am sure he made many more mistakes then shown in this picture.

I would ask for your money back. You don't want this guy to try and fix your system. At best he would be experimenting with your house and he isn't capable of getting the job done right. It takes many years to learn enough to be a good radiant installer or designer. Maybe sue him or just accept the loss.

I'm sorry Brad if you think this post is a little harsh. At some point in life you have to face reality. It does no one any good to sugar coat things. This guy must be discouraged from doing this again. It ruins the reputation of good radiant contractors to have people messing jobs up like that. This is one of the worst installations I have looked at.

JR

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Mike T., Swampeast MO

Has "Dr. Nick" from The Simpsons changed professions?

Your proposed solution [might] make it heat acceptably, but I certainly wouldn't want to pay the fuel bill!

The worst heating disasters I've seen and heard of always begin with a kitchen renovation and usually involve removing cast iron radiator(s).

S Ebels

Advice

1: do a heat loss for the room

2: Based upon that, decide if 10 btu/ft2 will get the job done

3: If not, supplement or rip out

4: If so, insulate with foil face foam at least 1 1/2" thick
(Caveat; the insulation will do it's job only if sealed well along the sides of the joists and the fintube is installed high enough in the joists to allow insulation underneath it)

5: Control it as a seperate zone from any other area in the house and be aware that workable water temps will start at 140 and go upward.


I experimented with this in my own house a few years ago just for the fun of it. It does work but response time is measured in days not hours depending on floor covering. The only way I would recommend doing it is with constant circ and reset of water temps. On/Off is NOT going to cut it. There has to be at least an inch or two between the bottom of the fin tube and the insulation to get decent convective air flow in the joist cavity. In my own house I got the best result using 1' of fin for every 2' (lineal) of joist space. Obviously in a 16' joist space for example you would want to evenly space the fin throughout the joist cavity.

All in all, it will work if the load is not too great. It's a very similar concept and system to Ultra Fin slipped over pex.

John Ruhnke

The tubes hang below the floor joices......

Steve,

I'll agree that you can make a fin tube radiant installation work if done properly. As I am sure you have done such. I have viewed some of your past jobs and they are very nice.

The fin tube in the picture is hanging below the bottum of the floor joices not in the floor joices. That makes it impossible to insulate underneath even if he wanted to. You would first need to extend the floor joices down lower or cut out all the piping and raise it up. Either way the cost to fix the job I am sure is higher then the cost of the original job itself. The contractor has to include ripping out the old work in his estimate. An added expense.

JR



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Brad White_9

Hi - I am the homeowner who had this installed in my basement. I appreciate everybody's comments to dat, no matter how blunt they may be. I trusted this contractor, but the minute I saw what he'd done I started to wuestion him. He's been very dismissive of my inquiries all along, and now I realize it's probably because he doesn't really know what he's talking about when it comes to radient floor heating.

I have not paid him for this work - luckily I spoke to Brad before I sent the check. In the meantime I do need to resolve the situation. He never explained anything about h

My sense is to find somebody who know what they're doing and have it replaced. In the meantime I have never had to deal with telling a contractor that his work is unacceptable, that I will not pay him for it. Does anybody have suggestions on how to go about doing that?

Brad White_9

My underfloor heating project

Hi - I am the homeowner who had this installed in my crawl space. I appreciate everybody's comments to date, no matter how blunt they may be. I trusted this contractor, but the minute I saw what he'd done I started to question him. He's been very dismissive of my inquiries all along, and now I realize it's probably because he doesn't really know what he's talking about when it comes to radient floor heating.

He never explained anything about expected BTU's/sq ft. The system works on my boiler the same way the radiators do - so there is no way it'll heat anything. What Brad didn't know is the heating is under my kitchen space only -while the crawl space is twice the size of my kitchen and runs under an adjacent room - so that makes the whole thing even more rediculous.

I have not paid him for this work - luckily I spoke to Brad before I sent the check. In the meantime I do need to resolve the situation.

My sense is to find somebody who knows what they're doing and have it replaced. In the meantime I have never had to deal with telling a contractor that his work is unacceptable, that I will not pay him for it. Does anybody have suggestions on how to go about doing that?

I am usually better at researching this type of thing before I go ahead with the work - I feel a little dumb for have let this happen, but apprecieate more input if you are willing.

John Ruhnke

Good legal type letter is best..................

Mrs Homeowner,

There are two ways to go about this.

The way that most people recommend is to send a legal type letter pointing out the problems with the job. I would also point out that you believe that he is not qualified to fix all of the problems. Point out the high fuel bills and the fact that a professional believes that it won't ever work right.

Actually the ball is in your court. He would have to sue you to win in court. So make sure to point out that if he ever tries to sue you for payment that you would bring all of your evidence to court. You don't need to actually collect any evidence now just theaten him that you have it should be enough. except I would take pictures before the old work is ripped out.

If it was me I would handle everything by a phone call to him personally. A letter is to much work and not needed. The point is to read his tone of voice when you talk to him. Most likely he will just act cowardly and back off. If he digs his heels in and threatens to sue if not paid, then I would do the letter. I would not spend money on a lawyer at this point.

After the phone call or letter it is over. Just wait and see if someone serves you with court papers. 98% of the time it just ends there. He knows he didn't do the job right. If so great you don't have to do any more.

If you get served see if it is small claims court. With small claims court in CT you can't bring any lawyers. It may be different in your state. You just gather your evidence and stuff. Send copies of your evidence asking him to drop the charges. If that doesn't work then consult a lawyer.

JR

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Mike T., Swampeast MO

How Did I Know?

"Kitchen renovation--get rid of the radiator." Here's the rest--"I used my plumber." [please no replies about plumber bashing]

In the absence of a written contract, "buyer beware" matters significantly to courts. I cannot fault this default.

Do your best to work with this contractor and WITHHOLD PAY until you have anything approaching a reasonable system. It is not unreasonable to expect this contractor to "eat" his INITIAL MATERIAL AND LABOR costs for the purpose of experience.

John Ruhnke

Loop holes.............

Mrs Homeowner,

I almost forgot the many legal loopholes that you can quote to him on. The contract has to be done a certain way. Does he even have a legal contract?

In CT you need to have a three day right of retraction written into the contract. You need to have your license number stated on the contract. Does he have a license? Less then 90% of the contractors follow all of the rules correctly. You could get out of paying him for not having a proper contract with you in the first place. Ask a contractor friend in your area to point out all of the contract stipulations needed and see if your contractor did it right. Again lawyers will charge you to look over his contract. You can call a few contracting firms here and there and ask questions to find out just how good his contract really is.

JR

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

ALH_4

UFF

How thick is your floor? Sometimes even Thermofin cannot deliver floor temps high enough to heat a space with a high heat load if the floor is thick.

You need extruded plates, though with older flooring like yours the contact is not nearly as good as with a plywood subfloor. Not that it doesnt work. There are many homes with subfloors just like yours that work great with extruded plates. A situation like this would make me nervous......I would be looking to put supplemental heat in the room.

Do you have the radiator for supplemental? Is it possible to reinstall it? Unless the house has been tightly insulated, it is likely you will need something more than the floor.

Ideally:

1) You either remove or abandon the baseboard elements in the crawlspace.

2) Install extruded aluminum heat transfer plates throughout the area spacing the tubes a maximum of 8-inches on center.

3) Reinstall the original radiator as supplemental heat. Instead you may opt for a kickspace heater under the kitchen cabinets. Control with a 2-stage thermostat.

Anything less would be taking chances in my opinion. On the positive side, the distrubition lines are already run for the manifold(s).

-Andrew

Christian Egli_2

A return of the good old Tom and Jerry cartoons

Just a creative thought for a repair

Agreed, this is a stretched version of radiant floor heat, but, what it looks a lot alike is the revered indirect heaters of the past.

Here's an interesting idea to look into.

Turn the crawl space into a sub-floor plenum (just like in today's state of the art ultra modern office spaces). To do this, tightly seal all of the perimeter, and insulate and seal the ground like you would an attic space. Then, poke exit holes in the kitchen floor (and perhaps the adjacent room for better circulation), don't forget to place the return grille somewhere.

It's not a full radiant floor, it's a combination and it's heat, modern indirect heat.

Brad White_118

Sari

Sari, Hi-

Glad you joined in. (You may choose to change the author line- It looks like I wrote it. No need to divulge the e-mail address though unless you want to).

Yes, I did understand that the kitchen was the only area to be heated and figured the crawlspace was not necessarily the same footprint, but still you are in the same pickle. I only wish you did not live 100 miles away- but you are getting good advice -the best- from thousands of miles away.. I will sit back and read a bit...

In a pinch, there are several contractors in your area both MA and CT who may be willing to take a look...Worst case short term is to get yor old radiator back in for the duration...

Uh, -Cheers!

Brad

Ted_9

Radiant, no, convection.

I agree with S Ebels.

You were not treated fairly.

This is how it should have been done. Aluminum plates under the sub floor, with a mixing control that has outdoor reset and boiler protection.

You should see what was there that we ripped out.



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

J.C.A._3

I'm agreeing with ....

Most everybody so far.(boxing in the fintube with "surround sound insulation" wouldn't be on the top of my solutions!)

Ted has shown the most respecteable solution pictures. This IS accepted practice by most pex manufacturers for a radiant/underfloor install.

Now, Ted...what the heck is that thermo-meltout connection for? Please don't tell me that it's a "tank Firomatic"! With all that new and beautiful equipment...your using 1920's technology to assure the oil flow stops in case of the unmentionable? Prove me wrong..PLEASE!!

I'm thinking it's something to shut off the weighted door on the air inlet to the room in case of...Am I right? Chris

Ted_9

yup

Yes JCA, you are right. It goes to the oil tank. Their oil man has no problem with it I guess. Unfortunatly, the homeowners were robbed by the first person to try the radiant so when I got there, it basically cost them 3 times as much as the original price. So I couldn't touch anything else. Believe me, I wanted to.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Weezbo

The RMBy and plates are not H.O. touches.

4 way mixers work well also.

even with though, Brads idea, of properly insulating the crawl space and applying a vapor barrier to the floor of the crawl space ees the rest of the story...:)

John Ruhnke

Very Creative.............

Christian,

Though I know it wouldn't make sense to do what you sugest. It does show a lot of good constructive creative thinking.

Thinking like that can sometimes lead to great inventions!!

JR

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Mike Reavis_2

I saw this once in DC

I guess the same guy struck out in MA now. The problem was that they were moving the water so fast that there was no heat jumping off the train, and this high velocity caused erosion corrosion. Them they let it freeze during a cold winter. -oy vey-

G Lyons

Botched radiant floor.

In all fairness to the installer wouldn't it be a good idea to tell the him that you are concerned about his installation and so you are going to wait and see if its going to work before you pay him. Introduce him to this web site! The floor is going to get warm with his installation. It will be interesting to see what happens.

The Romans did something like this. They built a fire in a furnace (below ground level) and channeled the heat and products of combustion through pipes or channeles under the tile floor of some of their buildings. This type of heating was or is even done in Russia.

It's already done, lets try it out, and cold weather is just around the corner.

John Ruhnke

It won't work right at all..........

G Lyons,

It won't work. The floor will never get warm enough for the client to notice and it won't get warm enough to heat the room when it is colder out. Also the client will spend tons of extra dollars super heating the crawl space in an attempt to get the system hot enough to work. I have years of experience and I have installed many radiant heating systems and I am telling you that it won't work. The job breaks every rule or installation guide that has ever been created for radiant. There is no excuse at all for doing the job like that. All he had to do is pick up the phone and explain part of what he wanted to do to anyone in the industry and they would have warned him not to do it like that. No this isn't anything like the roman hypocaust systems. In the hypocaust systems they let the hot flue gas travel under the floors. Flue gas gets very hot 300 to 400 degrees. They also enclosed the whole space so as to not let the heat out. Crawl spaces are meant to breath and they are open to the outside air.

JR

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Bill Clinton_5

ya just never know

I have difficulty believing such a set up would work in Massachesetts. I have difficulty believing it would work here in Northern California, but I have to believe it because I've seen it. Twice. Had been in for decades. The owners were happy. Neither had half the density of the fin tube in these pics and I can only guess inefficient as they come. But they did work. Go figure.

Bill

Gordy_2

What works?

It depends no? My analogy of this type of design is the same as trying to use a F/A furnace to heat a coil to supply a radiant loop. Any one have a schematic for primary / secondary duct work to heat a hydronic loop?

Someone out there will try to use a F/A furnace as a boiler. It would work but be very inefficient.

I think the term radiant floors needs to be more defined as to what is considered a radiant floor warming/ heating design..... this is does not make the list.
Also not all crawl spaces are ventilated to the outside John most are conditioned, and should be rightly so.

My .02

Gordy

Uni R_2

A different opinion...

I think it could easily result in additional comfort. It's just under the kitchen, it may take a few more BTU to warm a bit of land around the basement, but I think that it would also take the chill off the floor surface throughout the first floor and between the floor and heat from the surrounding rooms that kitchen could easily be far more comfortable. What the contractor did appears well done, whether or not anyone agrees with his strategy.

On a good, better, best pricing and options scenerio, perhaps this contractor only got paid to do the "good" strategy.

I'd actually wait until it gets cold out and then see how the comfort compares to any additional heating costs.

John Ruhnke

Wow!!!

Uni R

I suggest that you take a few class's on radiant heating to learn how it works and learn how it doesn't work well. Maybe you didn't look closely at the pictures?

The pipes hang well below the bottum of the floor joices. You cannot install insulation under the system without major modification. On any radiant floor heating system, Any tubes or heat emitters should be installed high up in the floor joices and well insulated underneath. Heat transfer plates would be a much better job. Any installation done on top of the floor would be an even better job.

The r factor of the floor is higher then the r factor below the heat emitters. Contrary to your belief, heat doesn't rise it travels in the path of least resistance. Most of the heat will travel downward into the crawl space. Some of the heat will travel up and heat the joice bay, most of which will bounce back down into the crawl space again. Only a very small fraction of it will actually warm the floor. Even a smaller amount of heat will actually reach the room above. Clearly not enough to heat the room.

If you can't recognize this as a bad installation then you need to educate yourself more in the field of radiant heating and you had better hold off on installing any said radiant heating until you do so. I sure hope you don't have any plans of installing such a system in the future.

JR

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Uni R_2

Pardon?

"The r factor of the floor is higher then the r factor below the heat emitters. Contrary to your belief, heat doesn't rise it travels in the path of least resistance."

Where did I say heat rises? I never said any such thing. I said they'll be wasting some heat but they'll have some additonal comfort. Who knows? They my find it worthwhile. We don't know what this job cost, nor what it would have cost to go PEX and plates nor what the incremental heating costs will be. If this job cost $1500 and PEX/plates would have cost $5000, then $200 a year extra in fuel would be a decision many people would take. Unfortunately, we don't know so it is tough to speculate.

The irony of your criticism, is that we're talking about convectors that actually heat the air, and hot air does rise but I'm sure you knew that.

John Ruhnke

RE:

Uni R,

You said "wasting some heat but they'll have some additonal comfort" That statement is off. More then 95% of the heat will go to the crawl space. They are wasting almost all of the heat. The amount of heat left over that actually makes it into the kitchen is no where near enough to heat the room in the winter.

Why are you defending this low ball bidder or anybody who does bad work like that?

I'm done with this thread. If you want the last word then by all means post.

JR



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"