A replacement garage for the Davenport House is currently being designed. It will include a 200 sf heated fitness room with extensive bookshelves. I am contemplating using radiant slab heating with Pex tubing and a small German boiler for heating system hot water and domestic hot water.
Questions
How reliable and what is the life expectancy of the Pex tubing and the system in general?
Who makes high quality energy efficient boilers for heating and domestic hot water?
Thank you?
Reliability of Radiant Slab Heating System
Reliability of Radiant Slab Heating System
Paul Harding FAIA Restoration Architect for FLW's 1901 E. Arthur Davenport House, 1941 Lloyd Lewis House, 1952 Glore House | www.harding.com | LinkedIn
Here is an abstract that might be of interest to you about the replacement at Jacobs 1 in 1984 (you might want to contact the owners about their system's life):
http://www.learningace.com/doc/1441606/ ... 010/jacobs
We are about to have our floors jackhammered later this week in order for a new hydronic geothermal system using water from an existing well to be installed. This is the boiler recommended to us by our contractor:
http://www.greendroplet.com/index.php/t ... 0-btu.html
http://www.learningace.com/doc/1441606/ ... 010/jacobs
We are about to have our floors jackhammered later this week in order for a new hydronic geothermal system using water from an existing well to be installed. This is the boiler recommended to us by our contractor:
http://www.greendroplet.com/index.php/t ... 0-btu.html
I have specified only a few radiant systems over the last 25 years, but each used Pex tubing (two beneath slabs, two beneath gypcrete on wood framing). I have heard of no problems from any of the clients with respect to the tubing. TIP: A series of photos with an overlaid tape measure at a clear datum point prior to cover up of the tubes is priceless for the future.
The later systems spec'd used Buderus boilers:
http://www.buderus.us/buderus-professionals/
The smaller wall hung units can be used in most smaller projects.
I have not combined the heating of the domestic and radiant water in the systems I have been involved with, as the temp needed for heating the slab could pose scalding issues at a tap. It may be possible with automated valves and separate temp settings...check with the manufacturer of the boiler.
Many loops are best for balance/control of the radiant heating.
The later systems spec'd used Buderus boilers:
http://www.buderus.us/buderus-professionals/
The smaller wall hung units can be used in most smaller projects.
I have not combined the heating of the domestic and radiant water in the systems I have been involved with, as the temp needed for heating the slab could pose scalding issues at a tap. It may be possible with automated valves and separate temp settings...check with the manufacturer of the boiler.
Many loops are best for balance/control of the radiant heating.
PEX and quality boilers.
Question:
How reliable and what is the life expectancy of the Pex tubing and the system in general?
Answer:
Wirsbo tubing is what I have used in the past they are the originators with 40 years of reliable service and over 15 billion feet of PEX (crosslinked polyethylene) tubing installed around the globe.
http://www.uponor-usa.com
Question:
Who makes high quality energy efficient boilers for heating and domestic hot water?
Answer:
There are many boilers to choose from. My suggestion is to select a reputable Boiler specific contractor that has installed the newer effecient boilers in existing systems. The contractor should also be the one that you will build a relationship going forward for annual service and troubleshooting concerns. I restored our previous personal residence a 1916 bungalow and converted/removed the archaic forced air system with a radiant system. The lower level, 1st, 2nd floors and domestic where heated from a single boiler Munchkin boiler with 5 zones including the domestic. I used the external Supestor tank for domestic hot water, aluminum heat transfer plates (joist track) for 1st story, lower level the existing concrete floor was removed with wirsbo & a new 4" concrete floor poured and Runtal Radiators at the 2nd story bedrooms.
The system has been live for 10 plus years and just annual service is performed on the Munchkin boiler, the house is currently leased to an Orthopedic resident at the local Hospital and they love the warm floors!
Last year I replaced the boiler in the McCartney house with a SlantFin Vsl-160 boiler. This style boiler is tankless. It has a 3-way valve that senses domestic hot water flow and switches the priority to domestic. It will remain in that mode as long as flow is sensed. The McCartney house is relatively small and part of the decision making for the wall hung unit was to maximize the space in the workspace where the floor mounted previously located. I looked at 2-3 tankless boilers and Slantfin was finally decided as #1. So we never run out of hot water at the shower, the boiler has a digital display to adjust the water temperature delivered to the fixtures as well as a separate display to adjust the temperature to the existing in-floor heat.
Good Luck!
http://www.slantfin.com/index.php/produ ... ciency-vsl
How reliable and what is the life expectancy of the Pex tubing and the system in general?
Answer:
Wirsbo tubing is what I have used in the past they are the originators with 40 years of reliable service and over 15 billion feet of PEX (crosslinked polyethylene) tubing installed around the globe.
http://www.uponor-usa.com
Question:
Who makes high quality energy efficient boilers for heating and domestic hot water?
Answer:
There are many boilers to choose from. My suggestion is to select a reputable Boiler specific contractor that has installed the newer effecient boilers in existing systems. The contractor should also be the one that you will build a relationship going forward for annual service and troubleshooting concerns. I restored our previous personal residence a 1916 bungalow and converted/removed the archaic forced air system with a radiant system. The lower level, 1st, 2nd floors and domestic where heated from a single boiler Munchkin boiler with 5 zones including the domestic. I used the external Supestor tank for domestic hot water, aluminum heat transfer plates (joist track) for 1st story, lower level the existing concrete floor was removed with wirsbo & a new 4" concrete floor poured and Runtal Radiators at the 2nd story bedrooms.
The system has been live for 10 plus years and just annual service is performed on the Munchkin boiler, the house is currently leased to an Orthopedic resident at the local Hospital and they love the warm floors!
Last year I replaced the boiler in the McCartney house with a SlantFin Vsl-160 boiler. This style boiler is tankless. It has a 3-way valve that senses domestic hot water flow and switches the priority to domestic. It will remain in that mode as long as flow is sensed. The McCartney house is relatively small and part of the decision making for the wall hung unit was to maximize the space in the workspace where the floor mounted previously located. I looked at 2-3 tankless boilers and Slantfin was finally decided as #1. So we never run out of hot water at the shower, the boiler has a digital display to adjust the water temperature delivered to the fixtures as well as a separate display to adjust the temperature to the existing in-floor heat.
Good Luck!
http://www.slantfin.com/index.php/produ ... ciency-vsl
McCartney - Meyers
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outside in
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40 years? I don't understand why one would install a radiant heating system even with this "promise". All materials oxidize, even PEX. The Eichler Homes in Palo Alto all used copper piping and its my understanding that there are 3 mechanical contractors that are in business solely to fix Eichler radiant systems. Most problems stem from pin-hole leaks created from oxidizing pipe.
The long term solution to radiant piping has never really been thought out. Existing systems will all inevitably fail, requiring replacement of the slab, etc. which is a very costly process. If one desired to install a truly long lasting system, I would recommend that 2 inch piping be installed with radiused corners, allowing a plastic pipe to be thread through the 2 inch pipe. Similar to electrical conduit, the plastic pipe could be removed and reinstalled when it needed replacement. Certainly more costly than that recommended by manufacturers, but much cheaper in the long run as slab removal would not be necessary.
The long term solution to radiant piping has never really been thought out. Existing systems will all inevitably fail, requiring replacement of the slab, etc. which is a very costly process. If one desired to install a truly long lasting system, I would recommend that 2 inch piping be installed with radiused corners, allowing a plastic pipe to be thread through the 2 inch pipe. Similar to electrical conduit, the plastic pipe could be removed and reinstalled when it needed replacement. Certainly more costly than that recommended by manufacturers, but much cheaper in the long run as slab removal would not be necessary.
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Roderick Grant
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- Joined: Wed Mar 29, 2006 7:48 am
Where does forced air stand as an alternative? The two houses in Southern Minnesota where I grew up had F/A, and it worked perfectly well in both instances. The newer house had a slab on grade with F/A and the floor wasn't at all cold, nor the heating bills high. The one big advantage is that the vents don't ever need to be replaced.
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Paul Ringstrom
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- Joined: Sat Sep 17, 2005 4:53 pm
- Location: Mason City, IA
Paul,
Do you have experience using Airfloor? Any idea of cost? We have our floor totally excavated right now. I'm going to have my husband look at this.
A failed system in many Usonians would still need the concrete removed since it adds 5" to original floor height. In our case the original floor to ceiling was only 7 ft.
The positive seems to be that you can cool the floor eliminating the need for the wall units (which were as much as the entire new hydronic system in our case (assuming 5 zones).
Do you have experience using Airfloor? Any idea of cost? We have our floor totally excavated right now. I'm going to have my husband look at this.
A failed system in many Usonians would still need the concrete removed since it adds 5" to original floor height. In our case the original floor to ceiling was only 7 ft.
The positive seems to be that you can cool the floor eliminating the need for the wall units (which were as much as the entire new hydronic system in our case (assuming 5 zones).
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Paul Ringstrom
- Posts: 4777
- Joined: Sat Sep 17, 2005 4:53 pm
- Location: Mason City, IA
Many people may not be aware, but Wright used this product in the Olfelt House, which is where I first heard about in many years ago.
I find it interesting that this company and product have survived for sixty years! Someone must be using it successfully.
I have not used the product or know the cost, but Mr. Olfelt is happy with it.
I like the fact that you can run the AC thru the system so you don't have to add a separate duct system.
I find it interesting that this company and product have survived for sixty years! Someone must be using it successfully.
I have not used the product or know the cost, but Mr. Olfelt is happy with it.
I like the fact that you can run the AC thru the system so you don't have to add a separate duct system.
Former owner of the G. Curtis Yelland House (1910), by Wm. Drummond
My husband looked at the air floor site last night and commented on how air is not as good as a conductor as water. In our cold climate with stone walls and lots of glass, he worries that air will not provide the warmth of water.
As most commentary on hydronic systems suggests finding a knowledgeable competent installer, he is researching and will discuss with people he believes to be competent.
We definitely will NOT be using PEX for our drinking water only for hydronics which will be non-chlorinated well water.
As most commentary on hydronic systems suggests finding a knowledgeable competent installer, he is researching and will discuss with people he believes to be competent.
We definitely will NOT be using PEX for our drinking water only for hydronics which will be non-chlorinated well water.
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Roderick Grant
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- Joined: Wed Mar 29, 2006 7:48 am
Mod mom, I don't know how cold it gets in your neck of the woods, but it can't be as cold as Minnesota. Forced air, whether through ducts or the Airfloor system, is underrated.
Based on the images on the Airfloor site, it looks a lot like the ancient system that FLW encountered in Japan, where heated air is sent through hollow tiles that make up the floor.
Based on the images on the Airfloor site, it looks a lot like the ancient system that FLW encountered in Japan, where heated air is sent through hollow tiles that make up the floor.
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outside in
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- Joined: Sat Jul 29, 2006 9:02 pm
- Location: chicago
again, if I were working on a new house, and the owners requested radiant heat, I would explore the notion of installing 2 inch dia. piping, attached to the reinforcing mesh, with radiused corners. Send a mouse through the final assembly and pull PEX tubing back through the piping. The pex will heat the air in the pipe, which will transfer the energy to the face of the "conduit" piping, thereby transferring heat to the concrete slab.
Just because it hasn't been done before doesn't mean its not a good thing.
Just because it hasn't been done before doesn't mean its not a good thing.
Interestingly enough, the Taliesin drawings for our house indicated 2" diameter pipes (on wider centers) for the radiant heating. During construction, the local plumbing and heating contractor proposed the design to be smaller pipes on tighter centers, presumably with tighter radii at the bends, as the smaller pipe "was more economical and would more evenly distribute the heat". In the correspondence, Davison notes the proposed change as adding unnecessary complexity, but allows it.
I wish Davison would have argued more strongly against it...eventually (hopefully far into the future) when the system does fail enough to be problematic, it would have made fishing PEX much easier. I'm assuming PEX still can be fished, but given the tighter radii, it may require slab removal at the ends of the pipe runs to remove the 180 degree bends to enable manual weaving of the PEX into the straight runs.
Though I understand Airfloor is a tried technology, I would think air's ability to warm the mass of concrete over a wide expanse is much less efficient than the greater relative mass of heated water over the same area.
I wish Davison would have argued more strongly against it...eventually (hopefully far into the future) when the system does fail enough to be problematic, it would have made fishing PEX much easier. I'm assuming PEX still can be fished, but given the tighter radii, it may require slab removal at the ends of the pipe runs to remove the 180 degree bends to enable manual weaving of the PEX into the straight runs.
Though I understand Airfloor is a tried technology, I would think air's ability to warm the mass of concrete over a wide expanse is much less efficient than the greater relative mass of heated water over the same area.
First off, I appreciate everyone sharing their knowledge and I am forwarding it to my husband. He will be discussing it with the heating contractor who he greatly respects.
Roderick-definitely not as cold as Minnesota but we've already reached 12 below this year and 20 below with the windchill. Remember there are a lot of stone walls that will be transferring the cold as well.
Our concern about air is partly experience with a cold floor. In our Noverre Musson (another apprentice) House w had a front "atrium" room that had a brick floor on slab that was 22 X 22 with garages on east and west side, glass on the south to the rest of the house and front door to the north with upper windows and insulated walls. There were high ceilings with a 6 X 12 skylight. Originally, the skylight could be removed and open to the elements but we replaced with it with a permanent energy efficient one in part to protect artwork. This room had it's own forced air HVAC system that we replaced with an energy efficient model. (I attached a link to some photos to provide a better understanding of this room). Despite the warmth from the forced air, when it was really cold, it was very uncomfortable to be in this room for an extended time. We want to make sure the Gunning House will be comfortable even on the coldest days.
Noverre Musson Atrium room: https://www.flickr.com/photos/125471081 ... 103895493/
As far as air-conditioning, the Gunning House remained comfortably cool all through last summer when there was nothing. Air from the creek flows up the ravine bringing cool breezes. We are toying with the idea of wiring for the zone wall air-con systems (mainly my idea to hold off on immediate installation because I prefer having windows open over the closed in house with air-conditioning). Once we put on a new white rubber membrane roof on our Noverre Musson House we hardly ever had to use AC instead opening up clerestory windows at night and closing up the house first thing in the am. We are thinking with our new white insulated roof on Gunning we might not need to add systems but will be ready if need arises.
Before we bought this house I got a guarantee from my husband that after restoration it would be warm. The Gunning children talk of loving the warmth of the floor when the temps were cold outside. I'm a little afraid of using forced air.
All that said, my husband is still researching and appreciates the information.
Roderick-definitely not as cold as Minnesota but we've already reached 12 below this year and 20 below with the windchill. Remember there are a lot of stone walls that will be transferring the cold as well.
Our concern about air is partly experience with a cold floor. In our Noverre Musson (another apprentice) House w had a front "atrium" room that had a brick floor on slab that was 22 X 22 with garages on east and west side, glass on the south to the rest of the house and front door to the north with upper windows and insulated walls. There were high ceilings with a 6 X 12 skylight. Originally, the skylight could be removed and open to the elements but we replaced with it with a permanent energy efficient one in part to protect artwork. This room had it's own forced air HVAC system that we replaced with an energy efficient model. (I attached a link to some photos to provide a better understanding of this room). Despite the warmth from the forced air, when it was really cold, it was very uncomfortable to be in this room for an extended time. We want to make sure the Gunning House will be comfortable even on the coldest days.
Noverre Musson Atrium room: https://www.flickr.com/photos/125471081 ... 103895493/
As far as air-conditioning, the Gunning House remained comfortably cool all through last summer when there was nothing. Air from the creek flows up the ravine bringing cool breezes. We are toying with the idea of wiring for the zone wall air-con systems (mainly my idea to hold off on immediate installation because I prefer having windows open over the closed in house with air-conditioning). Once we put on a new white rubber membrane roof on our Noverre Musson House we hardly ever had to use AC instead opening up clerestory windows at night and closing up the house first thing in the am. We are thinking with our new white insulated roof on Gunning we might not need to add systems but will be ready if need arises.
Before we bought this house I got a guarantee from my husband that after restoration it would be warm. The Gunning children talk of loving the warmth of the floor when the temps were cold outside. I'm a little afraid of using forced air.
All that said, my husband is still researching and appreciates the information.