Outdoor Wood Furnace Info
All-Purpose OWF Discussions => General Outdoor Furnace Discussion => Topic started by: TheCrier on September 15, 2010, 05:28:50 PM
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Hello everyone,
Building a new 30' x 54' two story shop and studio.... and had my 1.5" pex lines insulated and backfilled today. I insulated with 1/2" rubber foam then sprayed with soy based 3lbs spray foam to R36. This evening I found this site and was reading here that the lines shouldn't be spray foamed and that it will eventually become saturated with ground water. I was assured by the company who sprays this all the time that it will NOT absorb water and he waterproof with this product all the time. The installer seemed to know what he was doing.
What's up. Waste of money?
(http://i298.photobucket.com/albums/mm259/bructer1/IMG_0215.jpg)
(http://i298.photobucket.com/albums/mm259/bructer1/IMG_0218.jpg)
(http://i298.photobucket.com/albums/mm259/bructer1/IMG_0214.jpg)
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i have no idea...i have questioned this method but most seem to say if you use the proper foam you should be good
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Seems like a good idea..I know spray insulation is not cheap..My only question is how long will it last in the ground before it starts breaking down and or the R value goes down..Id say they only way it takes on water if a area is missed or you have a pin hole somewhere or when it starts to break down over time..
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to have any chance at all it must be closed cell foam (and i have been told this is never going to take on water but i personally have my doubts) i do know the open cell foam will suck up water
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Up here in Alberta the spray foam application has been used for years in the oil and gas industry. I've seen excavated 12" high pressure gas line below water table in muskeg areas look like new after 10 years. That's what gave me the idea to spray my hydronic lines. The new soy/plastic application is far more superior than what was used before 2005. I paid $2300 for for about 300' of lines and my walls and ceiling of my 8'x 12' cold room. (two trips)
Mind you, that was my price.
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Here is the cold room sprayed out with 5.5 inches of the same product.
I will install 1/2" recycled rubber floor tiles to stop heat transfer from the in floor heat next to my cold room.
(http://i298.photobucket.com/albums/mm259/bructer1/IMG_0435.jpg)
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I will be spray foaming my lines in place. I'll also be somewhat wrapping them in plastic after the foam. My plan is to dig the trench, lay a continuous run of plastic sheeting in it, lay the PEX in, spray foam it in place but lifted off of the bottom a couple inches, and then wrap the final foamed product with the remaining plastic and back fill the trench. I don't think the foam will ever get water logged. The plastic is to keep clods of dirt from accidentally being sprayed in with the foam and causing a weak point in the foam.
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for what it is worth boys and girls here is all i can find on the two types of foam commonly used...open cell foam is used in walls in a home basically because it will "move" with the home and not break away from the studs it has a less R value than closed cell
it will uptake water but it will also drain and dry out if not under the water (not good for underground)
closed cell foam has a higher R value, it is considered a vapour barrier but should not be used where any movement occurs, it will not "move" with the studs of your home but will crack and seperate letting cold and moisture in
With that info i think i will go with a pipe with the closed cell foam inside a plastic tile. and i think i will also run that down another water tight plastic tile (non perforated) if i am gonnna spend the buck on the pipe i am gonna put another waterproof jacket around it
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and if you look further you will find info that says closed cell does move and wont crack...sheesh. how do those sales guys do it...i think they must all be lying or really (like me) just don't know
i'm still gonna put another tile around it!
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quote from a boat manufacturer
"Is this foam water resistant?
"Yes, but with the following caveat. The foams that we sell are considered closed-cell, which means that each cell that makes up the foam structure is completely closed off from surrounding cells which prevents it from acting like a sponge. It is completely safe for this foam to be in contact with water for hours/days/weeks and even months with no adverse effects. However, it should never be submerged in contact with water permanently. Over a period of years the water contact can begin to soften the foam and cause it to lose its closed-cell status. This foam is designed primarily to be used as an insurance policy in case of damage/holes that could cause a vessel to lose buoyancy. Pinhole sized openings would essentially have no effect on the foam since the amount of exposure is so minimal but you should always make repairs as soon as possible to keep the foam effectiveness as good as possible. This will be the case will all after market closed-cell polyurethane foams and even manufacturer installed foams."
would you consider underground being submerged or not..i guess that is the question?
Thats it I'm done..there is too much info and i may go all the way over the insanity line if i keep looking
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willie, i'm not sure
I mean unless you have soil that is practically a muck and full of water year around I dont know. I dug a couple trenches today and the ground here is usually fairly dry, of course in the winter/spring its wet but I wouldnt' call it submerged by any means.
If i were going to do the spray foam lines I sure wouldn't hire someone to do it. I would just order a tiger foam closed cell kit and do it myself. they sell a kit thats around 600 dollars and it does a great job.
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Hey Willie, investigate soy based insul spray. Soy veggie oil mixed with some kind of plastic chemical concoction. Very minimal flex but in my opinion no need to wrap it in anything else, although I suppose it wouldn't hurt.
Last night we got 3" of heavy snow and I ran straight out to my freshly buried lines, then straight to my gauges.
A .3 diiffernce in temperature from my boiler to the heat exchanger at my furnace.
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thats good...... where in the world do you live getting 3"of snow already?
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thats good...... where in the world do you live getting 3"of snow already?
I'm in Bragg Creek Alberta, on the side of Banded Peak mountain. Suppose to snow again tonight but won't stay.
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Wow.... thats far north for sure.. If you have any big whitetails that need hunted just let me know!!! hahaa :thumbup:
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Deer around here are like rats. This is what was in my back yard this morning.... snapped this pic from my bedroom window buck nekid..... ^-^
(http://i298.photobucket.com/albums/mm259/bructer1/PA091040.jpg)
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Hey Willie, investigate soy based insul spray. Soy veggie oil mixed with some kind of plastic chemical concoction. Very minimal flex but in my opinion no need to wrap it in anything else, although I suppose it wouldn't hurt.
Last night we got 3" of heavy snow and I ran straight out to my freshly buried lines, then straight to my gauges.
A .3 diiffernce in temperature from my boiler to the heat exchanger at my furnace.
it's good to hear you are having great results with your pipes . I had good luck with mine 11 years ago but they have deteriated over the years and i will be replacing them this fall yet (i think) i am leaning toward the 6 inch tile witht two lines surrounded by foam..then i am gonna pu t that down another 8 inch non perfed tile. (i'm thinking here that not only will the second tile protect it more but the insulated line can now "move" a little if expansion and contraction with the heat makes it "grow" also i am thinking "dead air" around the lines has got to be better than damp soil and heat loss should be very minimul.
there is a farm show near me next week i am hoping to score a better deal on pipe there. there should be about 6 dealers at that show, i may be able to work them a bit and save a few dollars
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haha i figured you had moose after I looked up your location on google. there are some huge huge white tail in your province though!
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Hey Willie, investigate soy based insul spray. Soy veggie oil mixed with some kind of plastic chemical concoction. Very minimal flex but in my opinion no need to wrap it in anything else, although I suppose it wouldn't hurt.
Last night we got 3" of heavy snow and I ran straight out to my freshly buried lines, then straight to my gauges.
A .3 diiffernce in temperature from my boiler to the heat exchanger at my furnace.
it's good to hear you are having great results with your pipes . I had good luck with mine 11 years ago but they have deteriated over the years and i will be replacing them this fall yet (i think) i am leaning toward the 6 inch tile witht two lines surrounded by foam..then i am gonna pu t that down another 8 inch non perfed tile. (i'm thinking here that not only will the second tile protect it more but the insulated line can now "move" a little if expansion and contraction with the heat makes it "grow" also i am thinking "dead air" around the lines has got to be better than damp soil and heat loss should be very minimul.
there is a farm show near me next week i am hoping to score a better deal on pipe there. there should be about 6 dealers at that show, i may be able to work them a bit and save a few dollars
wille, go to www.urecon.com (http://www.urecon.com)
check out that pipe, it would do what you need without more pipe
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Hey Willie, investigate soy based insul spray. Soy veggie oil mixed with some kind of plastic chemical concoction. Very minimal flex but in my opinion no need to wrap it in anything else, although I suppose it wouldn't hurt.
Last night we got 3" of heavy snow and I ran straight out to my freshly buried lines, then straight to my gauges.
A .3 diiffernce in temperature from my boiler to the heat exchanger at my furnace.
it's good to hear you are having great results with your pipes . I had good luck with mine 11 years ago but they have deteriated over the years and i will be replacing them this fall yet (i think) i am leaning toward the 6 inch tile witht two lines surrounded by foam..then i am gonna pu t that down another 8 inch non perfed tile. (i'm thinking here that not only will the second tile protect it more but the insulated line can now "move" a little if expansion and contraction with the heat makes it "grow" also i am thinking "dead air" around the lines has got to be better than damp soil and heat loss should be very minimul.
there is a farm show near me next week i am hoping to score a better deal on pipe there. there should be about 6 dealers at that show, i may be able to work them a bit and save a few dollars
Thats why i wrapped my 1.5 inch pex with the 1/2 inch foam insulation first.....to allow for the small amount of expansion that is expected...... and for the possibility that the chemicals in the "green" foam would protect the pex from some sort of deterioration.
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thanks for the link scott
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thanks for the link scott
click on flexible systems or something.. They have test that pipe and at like 10 gallons a minute it can leave at 180 and reach an exchanger 150ft away at 179.5. The piping and vapor barrier qualities are nice
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Interesting discussion, I would question whether or not to put the plastic sheeting under your pipes. Seems like water would pool there instead of draining away. Maybe a bed of gravel instead? Just a thought.
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Willie, is that boat foam a pourable expanding foam or a spray foam? I've seen the pourable closed cell foam get a little wet eventually, but it stays buoyant for many years submerged in water, which means it's not completely water logged. Remember, this stuff is usually submerged in water 24/7 for several years. Not even waterproof boat hulls can handle that without a little TLC every now and then.
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it was from a boat palce but it is sprayed closed cell. from what i read jsut about everywhere they say it should last and it takes water on a bit becasue no closed cell foam is 100 percent closed...some cells burst when curing they say 3 to 4 percent could be open cell from this. They also say this smallamount should not effect the performance of the insulation
I guess each person has to decide for themselves. I am pretty sure i will go with it but like i said i will also run it inside another non perffed tile so i have 'dead air' around it instead of moist earth
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Likewise, that was my original idea as well, except I was going to use 3" electrical PVC conduit because it's a little cheaper than 4" drain tile. But, as someone on another forum quickly pointed out to me, the dead air around the PEX before you get to the insulation is something you have to heat and keep warm between the boiler and the house (i.e. HEAT LOSS). The goal is to move the heat as quickly as possible from the boiler to the house with as little loss as possible. I don't really think that the airspace inside of the drain tile would be a considerable heat loss, personally. But, it is something else you have to keep warm even if it's inside of the insulation.
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i would buy the dual lines allready inside the closed cell insulation and that is allready inside the 4 inch plastic tile then run this down another 6 inch tile (this is where the dead air would be) and i think there would be much less chance of moisture getting into the insulation inside the other tile and with this dead air around the insulated tile instead of moist earth..i think less heat loss?