Does anyone know if pex underneath a wood floor will cause it to warp over time? Seems like heat would cause damage, but I don't know. I know pex in concrete is probably the common application, but from a basement I could tack underneath the wood subfloor, thanks.
pex under wood flooring
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I don't personally know anything about it but I've looked into a little.
Google "retrofit radiant floor heat"
Google "retrofit radiant floor heat"
I've had under floor radiant since 2002 and see no detrimental effects. I've also had in floor under laminate for about 4 years with no problems.
Depends on a couple things. A floating floor is much less susceptible to shrinkage issues. An engineered floor that is a laminate of hardwood with plywood underneath is also more stable.
Full thickness plank hard or soft wood is most likely to have an issue. Flooring people can deal with this better than I can advise, other than the initial moisture content is extremely critical. As is the operating temp of the floor. A Warm Board type system or staple up, operating at higher temps is going to be more likely to have issues.
I would only use a floating floor over any radiant system.
Full thickness plank hard or soft wood is most likely to have an issue. Flooring people can deal with this better than I can advise, other than the initial moisture content is extremely critical. As is the operating temp of the floor. A Warm Board type system or staple up, operating at higher temps is going to be more likely to have issues.
I would only use a floating floor over any radiant system.
I want a slab foundation, the wife wants a basement to store crap, washing machine, etc. Most homes in Michigan have basements, but one flood is enough to make you not want one. When I lived out west during military tours most of our homes didn't have basements. I got used to living without one and then I come to a place that has them and I hate the idea of a flood again. Would much rather build a home with a slab and pex.
Karl_northwind
Minister of Fire
I have Uponor joist trak under 3/4" subfloor and 3/4" maple. it works just fine. the Radiant panel association and hardwood flooring assn. say to keep the water temps as low as possible. I have been keeping my place heated with 95 degree water for 5 years. The issues I've seen (elsewhere as a contractor) have been systems installed by people who don't know what they're doing. trying to heat an old farmhouse with 150 degree water under the floor with thin plates, melting the glue under the glue-down tile and generally causing a mess.
having built a house, I love having a basement. If I were doing it again, I probably wouldn't. I could have built a nice attached garage and workshop for what the basement+insulation+additional floor framing+reclaimed hardwood cost me. hindsight and all that.
I'm just starting some experiments with in-floor and will report back.
having built a house, I love having a basement. If I were doing it again, I probably wouldn't. I could have built a nice attached garage and workshop for what the basement+insulation+additional floor framing+reclaimed hardwood cost me. hindsight and all that.
I'm just starting some experiments with in-floor and will report back.
Bad LP
Minister of Fire
My gpycrete is under Santos Mahogany (engineered) and we limited the supply temp to 95 or so to prevent damage. Pump is Taco mixing block. No complaints and no temp swings. I think the design temp is 0F but I'd have to look at the display to confirm
maple1
Minister of Fire
Our kitchen has 3/4" T&G board subfloor, with 3/4" Pine T&G on top of that for the finished floor. It's about 20 years old now, and the pine is really getting ragged. Mostly from doggie claws, I think. Anyway, getting heat in the floor is something I've had in the back of my mind for when it comes time to replace the pine. Too much work for me to do something staple up, and I don't really want to raise the level of the floor much at all. Not really knowing what products are out there for this, would it be possible to do something like replace the 3/4" pine with 3/4" subfloor with 1/2" pex in it, then do thinner laminate right over that? The more I think about it, the more the 'don't bother' thing sets in. But warm floors would be nice.
Bad LP
Minister of Fire
Warmboard has a newer product (thinner than the original product) that might work great for you. I just looked it up last weekend for a friend doing a major remodel of his mud room, kitchen, laundry, and dining area but forget the letter designation they are using. Quick search will give you the data sheets. They are using tile over it. If the tile selections 10 years ago had the options out there now my whole first floor would be tile.
You come into my house with wet or dirty shoes and walk on my wooden floors I'm getting upset. Entry, kitchen, hall, bath and laundry have at it. Don't drop anything in the kitchen as there is no hope in saving it.
This is what I used under my laminate floors. It's 5/16 tubing in 1/2 inch plywood panels. If you choose the right thickness laminate it's just a fraction thicker than a 3/4 inch floor. I know what you mean about doggie damage. The reason we chose Brazilian cherry isn't because we liked it but because it resisted the toenails on Molly the chocolate lab. Molly's in heaven now but the floor is still with us.
(broken link removed to http://www.viega.us/xchg/en-us/hs.xsl/7119.htm)
(broken link removed to http://www.viega.us/xchg/en-us/hs.xsl/7119.htm)
Controlling humidity has a lot to do with the movement of solid wood flooring. If you are in an area that sees wide humidity change, consider adding appropriate equipment to keep it stable.
A troubleshooter from NOFA told me of a home built on the coast of Maine. They installed some wood flooring brought in from Utah.
They wood took on so much moisture it actually pushed the sill plates and walls out an inch or so.
Wood with high moisture content that drys can "panelize" where large sections move together and you get large gapping at random locations.
The engineered products are much more stable, look for brands that use hardwood for the core layers. The soft core engineered or laminates can damage easily from dropped objects. It's worth a little extra $$ to get top quality flooring.
Radiant and wood flooring work fine together, as mentioned above, low temperatures, outdoor reset controls and watch the humidity. A good flooring contractor has a moisture meter in his toolbox and allows the solid wood to acclimate to the jobsite before installing.
Karl_northwind
Minister of Fire
I've got staple up pex and 3/4" solid beech flooring nailed down on top. No problems been there for 5 years now. I run the water at 140.
Just have to watch where the flooring nails are going. My nails were slightly longer than the thickness of the subfloor and the hardwood tounge. You can imagine where this is going...... Thought I was doing so good and then a year later I had a leak. The nail finally rusted out and the PEX started to pee out a little stream of water. Easy to fix but still a good thing to avoid. Had the location of the PEX marked on the floor so I could see it as I installed but forgot to mark the turns at the ends!
Just have to watch where the flooring nails are going. My nails were slightly longer than the thickness of the subfloor and the hardwood tounge. You can imagine where this is going...... Thought I was doing so good and then a year later I had a leak. The nail finally rusted out and the PEX started to pee out a little stream of water. Easy to fix but still a good thing to avoid. Had the location of the PEX marked on the floor so I could see it as I installed but forgot to mark the turns at the ends!
I retrofit Thermofin C plates under 3/4 osb subfloor with narrow oak strip and tile above.
No warping or noise whatsoever in three years of operation.
Swelling and shrinkage is present with seasonal changes in humidity, but that was present with electric baseboard heat as well.
Low water temperature is key.
Industry recommendations were that water temperature should not exceed 145°F, and surface temperature should not exceed 85 degrees.
I took an angle grinder with cutoff disk to the flooring nails sticking through the subfloor. Kids: "Why is Dada shooting sparks across the basement."
seems like you should let hardwood acclimate before installing from what I have read to avoid the . Not sure if anyone has done that with new installations.
I have 300 sq ft of Maple floor with 1/2" lex tube stapled underneath it. It gets dry in the winter and shrinks up a bit. I have not seen any problems in 3 or 4 yrs . I keep the water temp @ 158-175 degrees but not for long at higher heat. I have noticed it squeaks a little bit. I ran the tubes every 8" . Some of the tubes are an inch down from the OSB and some are stapled right up to the bottom of the OSB. No problems but maybe I should take a look and take off some of the fiberglass insulation.
My personal cut off for any type of "under the floor" system is when design heat loss gets over 13-14 btu/sq ft. Above that there are too many ???? for me to be comfortable with it. A new well insulated house can hit those numbers pretty easy but an older house with higher heat loss is not a good candidate for any under floor system in my book.
Look for an underlayment type product that goes on top of the subfloor like Viega Climate Panel or Warmboard.
I have Viega under the birch flooring in my living room and it heats beautifully with no problems at all regarding warping or gapping. Humidity plays a huge role in that also.
Any and I do mean ANY solid wood flooring will move whether is is a heated floor or not. It's the nature of the beast. The engineered wood floors are better in this regard.
We are helping a young guy work through this very issue with his system as we speak.
(issue being btu/sq ft) Only his problem is in the opposite direction.
He's a well driller by trade and he put down 4 200' loops to serve a 4ton ground source heat pump which he purchased over the counter at a local supply house.
The company that sold him his system said "sure you can heat that no problem".
Problem is, the heat loss of the house is 81,000 btus and the heat pump will do 46,000 on a good day. Add to that a system that will only transmit about 15-20,000 (near as I can figure) and you have a very cold house for wifey and 3 kids.. WAF is very low on this one...
A water to water geo will put out 120* fluid temps which are fine for a gyp or concrete floor system.
For under floor system you are typically going to need 150*+ and in his particular situation you would need an honest 180-190* water temp. The poor kid invested thousands of dollars in his DIY system and it will not heat his house below 45* ambient outdoor temps.
Look for an underlayment type product that goes on top of the subfloor like Viega Climate Panel or Warmboard.
I have Viega under the birch flooring in my living room and it heats beautifully with no problems at all regarding warping or gapping. Humidity plays a huge role in that also.
Any and I do mean ANY solid wood flooring will move whether is is a heated floor or not. It's the nature of the beast. The engineered wood floors are better in this regard.
We are helping a young guy work through this very issue with his system as we speak.
(issue being btu/sq ft) Only his problem is in the opposite direction.
He's a well driller by trade and he put down 4 200' loops to serve a 4ton ground source heat pump which he purchased over the counter at a local supply house.
The company that sold him his system said "sure you can heat that no problem".
Problem is, the heat loss of the house is 81,000 btus and the heat pump will do 46,000 on a good day. Add to that a system that will only transmit about 15-20,000 (near as I can figure) and you have a very cold house for wifey and 3 kids.. WAF is very low on this one...
A water to water geo will put out 120* fluid temps which are fine for a gyp or concrete floor system.
For under floor system you are typically going to need 150*+ and in his particular situation you would need an honest 180-190* water temp. The poor kid invested thousands of dollars in his DIY system and it will not heat his house below 45* ambient outdoor temps.
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maple1
Minister of Fire
IMO Geo ain't always what it's cracked up to be.
In the above example, not only is it not heating his house - but I suspect the electricity cost for pumping out of those 4 holes 24/7 would also be a hit. If they're closed loops, might not be as bad - but those pumping out of wells then dumping back into another one, well, pumping water out of wells uses some juice. I think almost everyone I know who has put a Geo system in has had unexpected suprises to their power bills.
In the above example, not only is it not heating his house - but I suspect the electricity cost for pumping out of those 4 holes 24/7 would also be a hit. If they're closed loops, might not be as bad - but those pumping out of wells then dumping back into another one, well, pumping water out of wells uses some juice. I think almost everyone I know who has put a Geo system in has had unexpected suprises to their power bills.
Karl_northwind
Minister of Fire
I remodeled my house 3 yrs ago. The dinning room living room area has laminate with thin foam under. I had lots of spare 1/2 in plywood so I ripped it into 8 in strips, nailed it down with 1/2 gaps and placed 3/8 pex down. I bought 2 huge rolls of aluminum foil on ebay for $10 and placed the foil down on the plywood, pressed the pex into the grooves and placed foil on top. Then I installed the laminate. Works great, no cold or hot spots and recovers quickly
The rest of the house has staple up 1/2 with home-made aluminum plates. The plates were made from aluminum paper backed flashing with the groove pressed in from a die and log splitter.
I keep the house at 70* but if I run the pellet stove I have to set it at 75* for the same comfort level because of air movement
leaddog
The rest of the house has staple up 1/2 with home-made aluminum plates. The plates were made from aluminum paper backed flashing with the groove pressed in from a die and log splitter.
I keep the house at 70* but if I run the pellet stove I have to set it at 75* for the same comfort level because of air movement
leaddog
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