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Posted: Mon Aug 25, 2008 2:38 pm
Both Wrought Iron and Copper were used. Wrought Iron appears to last longer and heat a little better because of the larger surface area. Most of the Eichler Homes in CA are copper. Whatever the material, it's not a very "eternal" way to heat - in time, the material will oxidize and fail.
Posted: Mon Aug 25, 2008 2:47 pm
Wrought Iron appears to last longer and heat a little better because of the larger surface area. Most of the Eichler Homes in CA are copper. Whatever the material, it's not a very "eternal" way to heat - in time, the material will oxidize and fail.
You don't know what you are talking about. Wrought Iron pipes rust and decay. Copper pipe will not, as you say, oxidize and fail. Look at all the houses built with copper pipe for water lines. Copper pipe is standard and still used today.
Posted: Mon Aug 25, 2008 4:35 pm
Such a kind response.
Wrought Iron was used in most early Usonians such as the Jacobs and even the Unitarian church in Madison. Copper was used later on, but because of the thin wall section has exhibited a tendency to leak over time - it starts with small pinholes, which then become larger over time. Both materials oxidize, and will require replacement. There are three mechanical contractors in Palo Alto that do nothing but run around fixing Eichler homes with copper radiant heating.
I thought the purpose of this website was to provide information, not insult others.
Posted: Mon Aug 25, 2008 4:55 pm
All the 3 houses in Canton, Ohio used cast iron. And all were built after the Pleasantville usonians. The success or failure of the pipes had to do with installation and not much with the materials used. The pipes contact or lack of contact with or embedded in cement seem to have been the reason of failure-- than pipes were to be installedi in the gravel as specified by Wright.
On a major repair of the Rubin usonian we discovered that the floor was one monolithic pour. Footers and 4 in. mat poured at same time of construction ( at least in the area were the system leaked) We found the pipes 20 or so ft away in excellent/clean/non- corroded condition. Were the pipes were in cement it failed--- elsewhere in gravel, the pipes were fine.
Posted: Mon Aug 25, 2008 5:32 pm
Agreed, copper and concrete do not mix. The copper reacts with the other chemicals in the concrete and it should be sleeved or coated for such an application. Other grades of copper should also be considered. Additionally, the vibration of the pipes during use can cause vibrations and wear pin holes in the surface over time because it is a relatively soft metal. Essentially, you're likely doomed if you have this condition -- PEX tubing is the way to go now. The heated slab in my parents' 1980's home sprung a leak at least 10 years ago...
Posted: Mon Aug 25, 2008 6:58 pm
Outside â€“ I fail to be polite when someone distorts the facts.
Every Wright Usonian house drawing, whether W.I. or copper, Iâ€™ve seen they always specify the pipes be imbedded in gravel and not in the concrete. I visited Zimmerman on several occasions. That house used steel and the steel literally decayed. I saw the photos. Furthermore, John Payneâ€™s house in NJ had steel pipes that decayed. There used to be an entire photo essay on FLWBC describing how he had to replace his entire floor/slab.
I suspect that the decay of W.I. pipes depends on the water table of the house itself. As an example when you dig down into the ground far enough it fills up with water. If the house is on the top of a hill or slope it may not fill up but drain away. W.I. pipes submerged in water will decay over 50+ years. Copper does not.
I am not sure about what to say about DTC's expereince. Perhaps the Canton houses all have good water tables.
Posted: Mon Aug 25, 2008 7:42 pm
Also the type of gravel used is important. It was reported that Mr. Weltzheimer made a substitute using a slag (instead of gravel, specified by Wright) the slag was like a gravel but it was not stone, but an end product of the iron ore process. It was by no means ph neutral but tested very acidic.
end result --- the slag may have shortened the life of the cast iron pipes and the gravity heat system?
Posted: Mon Aug 25, 2008 8:25 pm
I just pulled the Haynes gravity heat working drawings. Wright states to use "Type K Copper Tubing." I found this on the net about type K.
There are three series (plus DWV):
K, having the heaviest walls, typically used for underground burial.
L, used for most purposes.
M, with the lightest walls, used for drainage and other low-pressure applications. (Some plumbing codes do not permit M.)
Posted: Mon Aug 25, 2008 8:26 pm
One Usonian drawn in 1950 shows the 2" W.I. (wrought iron) at the top of the crushed rock ballast, apparently contacting the underside of the slab.
The specification reads as follows:
ALL BEARING SHALL BE ON SOLID GROUND FREE FROM LOOSE AND DELETERIOUS MATTER. ANY FILL REQUIRED BENEATH FLOOR AREAS SHALL BE OF THOROUGHLY COMPACTED EARTH -- PUDDLED AND TAMPED -- OR OF CLEAN BROKEN STONE. ALL FLOOR AREAS OF BUILDING TO HAVE A MINIMUM OF 5 1/2" BROKEN STONE (OR CLEAN GRAVEL) FILL BENEATH FLOOR SLAB -- PLACED IN TWO LAYERS: ONE TO BOTTOM LEVEL OF HEATING COILS, TWO TO FILL IN AROUND COILS.
"Expertise" as a daily matter (are any of us really
experts, in anything ?) involves re-research (not mere memory) and specifics (examples, including ones that don't necessarily support one's preferences and biases).
Posted: Mon Aug 25, 2008 10:16 pm
Ok, we've all determined that cast iron, wrought iron and copper have been used in the past - and there seems to be a lot of discussion regarding the way in which the pipes were placed, i.e. in contact with concrete, gravel, etc. But yet no one has addressed the issue of oxidation of the pipes - heated water carries oxygen, and oxygen will combine with iron, steel or copper and oxidize - simple science. In time, wall thicknesses will be reduced and the pipes will leak. I continue to be perplexed by this attitude that persists in this website that if Wright specified it, it must be good - radiant heating is, at best, a temporary source of heat. In time, it will degrade and rot. Hardly a sound approach to construction.
Posted: Mon Aug 25, 2008 10:28 pm
"radiant heating is, at best, a temporary source of heat. In time, it will degrade and rot."
Not sure who that is speaking, but it's becoming clearer (to me) that Wright had virtually no carved-in-stone rules. Rather, he seems to have been happier continually revising, rethinking and (especially) inventing and re-inventing. Whether it was the naming of rooms (kitchens, for instance), detailing of firepaces, or which typewriter face should represent Wright to the outside world, all and everything was in flux.
Can any insiders verify or refute this impression ?
Is anybody casting PEX in a concrete slab these days, or is it meant only to be used in a "dry" installation -- clips, tracks, etc, beneath a wood floor ?
Posted: Mon Aug 25, 2008 11:05 pm
But yet no one has addressed the issue of oxidation of the pipes - heated water carries oxygen, and oxygen will combine with iron, steel or copper and oxidize - simple science. In time, wall thicknesses will be reduced and the pipes will leak.
In my past PEX research I found that PEX was modified to include an aluminum liner. Air bubbles in the line would weaken the PEX. The new aluminum liner prevents this.
As for copper, houses have used this material for both hot and cold water for years. It is still standard in the industry. So, I assume no issues past or present with pipes oxidizing.
I donâ€™t know about other materials and air bubbles.
Posted: Mon Aug 25, 2008 11:10 pm
Clogging ? Weren't we talking about pinholes and leakage ?
Posted: Tue Aug 26, 2008 5:26 am
outside in wrote:Ok, we've all determined that cast iron, wrought iron and copper have been used in the past - and there seems to be a lot of discussion regarding the way in which the pipes were placed, i.e. in contact with concrete, gravel, etc. But yet no one has addressed the issue of oxidation of the pipes - heated water carries oxygen, and oxygen will combine with iron, steel or copper and oxidize - simple science. In time, wall thicknesses will be reduced and the pipes will leak. I continue to be perplexed by this attitude that persists in this website that if Wright specified it, it must be good - radiant heating is, at best, a temporary source of heat. In time, it will degrade and rot. Hardly a sound approach to construction.
I could not agree more. It only makes sense to use products WITHIN assemblies be it a floor/slab, walls, ceilings, or roof that are solid, proven AND advanced technology, this extends the life of the built work in a manner that is consistent with historic preservation standards. On Davenport within the historic walls we used the finest state-of-the-art technology that is available provided that it had demonstrated track record as opposed to products that are new and unproven. We live in a different time and technology from FLW's time. The key to using these strategies is working with a competent restoration architect as opposed to a wanna be architectural consultant.
Posted: Tue Aug 26, 2008 9:46 am
Aggressive water is water that can cause corrosion in copper pipes. It is a real and growing problem in many parts of the country. Leaks are developing in new homes that are less than 2 years old in some cases. These leaks can cause high water bills and structural damage. Homeowners or municipal water systems that obtain their water from wells are susceptible. Rarely, does surface water (that obtained from rivers, lakes, etc.) become aggressive.
The causes and mechanisms that are responsible for the corrosion are not always the same. Water that is slightly acidic is sometimes to blame. High levels of dissolved minerals and carbon dioxide also can cause problems. High levels of chloride or sulfate can be serious.
Poor workmanship can lead to corrosion. Plumbers who use excessive amounts of flux when soldering and/or leave excess flux on copper pipe and fittings are to blame as well. Flux is an acid that is brushed on copper pipes and fittings that allows solder to bond more easily to copper. Municipal waters works usually have chemists who regularly test the quality of the water being drawn from wells, rivers, lakes, and aquifers. These chemists are responsible for maintaining water quality. Not only do these individuals treat water to make it safe to drink, they sometimes alter the water chemistry to make it less aggressive. Some municipal water works add corrosion inhibitors to the water.
Believe it or not, these chemists try to adjust the acidity and hardness of the water so that it actually coats the inside of your pipes with a thin scale of calcium carbonate. This scale can protect copper pipes from corrosion by insulating' the copper from the aggressive water. This may be the reason why the pipes in your parents house are not suffering from corrosion. New copper is very susceptible to corrosion, as the protective scale has yet to form.
Water chemistry can change. Those parts of the country that are experiencing growth may find out that their municipal water works are either drilling new wells, or sinking existing wells deeper. In either case, aggressive water may be mixed or injected into a previously non-corrosive water system.
http://www.toolbase.org/Technology-Inve ... ipe-lining