Radiant system has died

peterwdrake

Hi,
Your site was recommended to me. I'm attaching 2 images; a picture of our living room in our 1953 slab ranch house in Montclair NJ and a detail of our now-dead radiant heat system. The house has its original radiant heat system, with black-iron pipes in the 16" concrete slab. We has a leak about 20 years ago and were told to abandon the system. However, I used Silver king Safe Liquid and over 4 years reduced the leaks to a slow weep. Three days ago something must have snapped, as we lost all heat, and there was zero pressure. I thought it was a failed col water intake, which had happened before. Sure enough, the intake was bad, but after replacing all that we could not maintain pressure. There are 2 zones. Zone a went steadily down as soon as the cold water feed turned off, while zone B plummeted. This is indicative of 2 major breaks although none of course are visible. It is far beyond the capacity of Silver King Safe Liquid to fix.

So, it seems we must finally abandon the system. The house was designed around radiant heat and frankly radiators would look awful - see picture of living room. We have ducted a/c so of course the cheapest thing would be to add heat to it. My wife and i hate hot air heat. The plumber who was hear today mentioned a radiant ceiling, which we've never heard of. Another contractor said we could look at pouring a "mini slab" with new tubing in it over the existing slab. There are also wall-mounted radiators, baseboards, etc.

To be honest, we are in shock. We don't have unlimited funds and don't really know where to start. We are very fortunate in that our dearest friend and neighbor is a commercial architect and knows a lot about systems of all kinds. Have any of you faced this? How did you proceed? Fortunately the weather is getting warmer so it's not an emergency.

Thanks very much for any advice.
Peter and Kay

EzzyT

@peterwdrake radiant ceiling would be a better option and could be a lot less of a overall cost then reworking in a new radiant floor.
Either radiant floor or ceiling will require insulation below or above to prevent heat migration away from the rooms.
With radiant ceiling you might be able to get away with partial coverage verses radiant floor you will definitely need complete coverage.
We’ve reworked a lot of these systems in the past and we had great success with radiant ceiling route.
Before any work is to commence you’ll need a heatloss analysis and design done in order to make sure the radiant options will be the best route.

Ironman

I'd recommend that you contact EzzyT. You won't find any better.

peterwdrake

Mr. Travis, I will contact you, but what is the loss in ceiling height with a radiant ceiling? Our ceilings are already low at 8' One option I've read about is cutting channels into the existing slab for new tubing and then a thin coat of concrete over it. We very much like our polished concrete floors. Thanks.
P

EzzyT

Total loss of ceiling height would be 11/4”. If you go the floor route then you have to take in consideration of your doors. I would try to avoid having to go the floor route in your situation.

EzzyT

You’ll know the height difference if going the floor route verses the ceiling route.

GroundUp

I would also aim for the radiant ceiling route, as you can run higher surface temperatures meaning potentially less emitter surface and not have to fight the doorways, cabinets, finished floors, etc. It's not cheap but it's going to probably be the most cost effective means of radiant. Out of curiosity though, what kind of piping is in the slab? Is it all black pipe in there?

peterwdrake

Is there a danger of the now-unheated slab becoming clammy using ceiling radiant? We have no carpets and don't want any. Thanks.
P

peterwdrake

It is all black pipe in the slab.

PerryHolzman

A long shot - but have to ask.

What is the layout of the black iron pipe. It was rare; but some people thought ahead and essentially did either pipes that went completely though the slab edges with external to the slab connections between pipes, and I've seen one person sketch out that they were going to do large radius U-bends with long straight legs, with the ends again outside of the slab edge.

On the rare chance you have one of these designs you could likely either identify the leaking pipe and abandon it; or cut the connecting pipes off and run pex tubing down the existing pipes.

Next comment is that I understand that you like your slab heat; and you may not feel that you have the height to give up on a ceiling radiant system.

Yes, it is possible to cut deep groves into your slab and insert pex tubing, and then fill the grooves with a mortar mix.

You would likely need to cover the entire floor to hide the new work. Might I suggest a Terrazzo floor. They are not cheap. But look great and are very durable, and come in many different colors and mixes (you can even do patterns like you see in airports and other commercial buildings).

https://www.homeflooringpros.com/terrazzo-flooring/

I wish you the best with this,

Perry

kcopp

Bummer.
I know you said you didn't want radiators... how about cast iron baseboard? Low profile and the heat output is super nice.
Just a thought...

BillyO

low profile panel radiators similar to hydronics alternative style also an option

peterwdrake

These are all great replies - thanks. I have actually "seen" the pipes. 20 years ago, when we had our first leak, the utility company sent over a person with an infrared camera. We heated up the pipes and they glowed like neon in the slab. They do not run outside the slab. There are also several loops in each of the 2 zones, with a return manual for the larger zone. I'm told it would be next to impossible to run pex through all that, would still require some digging into the floor, and would not be as efficient as the iron was. Our first choice would be cutting grooves then putting cement or terrazo over it. The ceiling is intriguing, but as I asked before, is there a danger of the cold slab becoming clammy in the winter?

hot_rod

I would also suggest radiant ceiling as the least intrusive hydronic option. You will not have the warm floor feeling anymore if that is a key desire?
Grooving concrete is a messy, expensive option, I doubt that is viable.

If there is a piping path, panel radiators near those glass areas is an option. We see more options for low temperature panel rads with some fan convection.

Looks like you need an entire boiler room upgrade also is the boiler 1953 vintage also? if so, adding heat to the forced air may pencil out the least expensive option.

Depends on comfort, how long you plan on living there, resell options, $$ etc. Tough choice, but that system certainly has provided a long, comfortable service.

peterwdrake

I did look at the terrazo link and the stuff is beautiful and totally out of our price range. I had never heard of radiant ceilings before yesterday. They seem counterintuitive, but so many people are recommending them. We have to check them out. Fortunately, we have a few months to decide, and pick a bank to knock over to obtain the funding.

hot_rod

Think of radiant heat energy like the sun. As soon as you have a line of sight the energy travels at 186,000 miles per second to any surface it sees. A a cold day steeping out of a shadow and into the sunlight, you feel that energy almost instantly.
So the energy travels exactly the same from top down or bottom up.
Years ago a lot of electric radiant ceilings were installed in areas with low electric rates, Montana, Minnesota are a few examples. It is a clean comfortable heating transfer with radiant whether it comes from the floor, ceiling or walls.
It will still gobble up a few inches of head space if you do a ceiling system, of course. And some trim detail around all the nice woodwork you have.

Looks like this, at a friends home.

peterwdrake

It does look like the way to go. Could you give us a BALLPARK of price per square foot? It's about 2000 square feet, about 60% of which has popcorn ceilings, the rest are smooth. Our 1953 boiler is gas fired and we have a 1953 RUUD water heater that still works great. Ceiling height is 8 feet now. Thanks.
P&K

EzzyT

@peterwdrake we don’t discuss pricing on the forum.
There is no ball park pricing per square foot it all comes down to the heatloss analysis which in then will a design be able to be drawn up.

peterwdrake

Oh, sorry.
P

peterwdrake

I checked with out utility company, PSE&G in NJ, and they do not do free home energy audits. Where do I find an independent auditor whose report I could use with various contractors in soliciting bids for a new system? We are in Montclair NJ, 07043. Thanks very much. P

EzzyT

As far as I know of there aren’t any independent companies that will do a free energy audit for your home one must pay for that and if there are good luck getting any time soon.
We do our own Heatloss analysis and designs which you’d have to pay for. Once the design has been completed we will offer you a quote to perform the work based on the design.
You do have the option to have other contractors bid on the work based on the design.

mattmia2

I'm curious about that water heater. Is it monel or copper having survived almost 70 years?

peterwdrake

OK, thanks. I certainly expect to pay for the audit; I just want to be able to use the audit when soliciting bids and not pay each contractor to do an audit/analysis. I would like to believe it's based on calculations/measurements and would be pure data useable by any contractor. I did find one company on the Residential Energy Services Network. P

PerryHolzman

Look on the internet for Energy Audits. A reality is that the best feature of this is the before and after air blower door test and recommendations on items installed in your house. They should also tell not just what you need to do, but for air leakage issues how to fix it yourself if you are up to the work.

The one I had done when I purchased my 1954 house in 2001 did not include a detailed heating/cooling loss load suitable for a Heating & Air Conditioning contractor to use.

But we dropped the air leakage into my house from massively more than normal to what is considered energy efficient (and enough to ensure adequate air exchange - you don't want to get too tight either).

That cost me a case of caulk, a few cans of expanding foam, and several long days of work by myself. With that - I passed the post repairs air blower door test.

I also got some energy efficiency upgrade money with the house loan and changed the windows on two sides of the house (the largest windows). Technically, not cost effective; but, made a noticeable difference.

Over the years I have installed more modern lighting where appropriate (and ignored lighting that is rarely used), a highly efficient boiler, etc.

After you get your air leakage under control and other obvious issues... You can do your own heat loss for heating. Slantfin (radiators) has a program you can download. I estimate that it accurate to about 20% based on my personal experience with it.

I wish you the best,

Perry