logstor vs. thermopex vs. other

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warno

Minister of Fire
Jan 3, 2015
1,237
illinois
I have read through the underground lines thread here in the boiler room a couple times now. It seems everyone leans more towards the "foam in trench" method for underground piping.

I'm asking for reviews from people who have tried the other brands of piping such as logstor, thermopex, or any other brand.

I don't want to start a this is better than that debate, i'm just looking for personal experience with whatever method you chose.

If you could state your product of choice, distance piping is ran, method for back fill, and if you know your heat loss numbers to the ground.

Please and thank you in advance.
 
I have read through the underground lines thread here in the boiler room a couple times now. It seems everyone leans more towards the "foam in trench" method for underground piping.

I'm asking for reviews from people who have tried the other brands of piping such as logstor, thermopex, or any other brand.

I don't want to start a this is better than that debate, i'm just looking for personal experience with whatever method you chose.

If you could state your product of choice, distance piping is ran, method for back fill, and if you know your heat loss numbers to the ground.

Please and thank you in advance.

I used Microflex. Dual 1" pex lines inside a 5" diameter foam insulated pipe. Very pleased with it. Although it was hard to find.

Have two lengths, one from the furnace to the garage that is 25' and one from the furnace to the house that is 55'. It's buried one foot in the ground. Less than 5 degrees temp loss to the garage.

http://www.microflex.be/media/2617/mic_086412_lfl_RenEnergy_EN.pdf
 
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First winter with 70 ' of 32mm (1and1/4") Logstor from boiler shed (Econoburn 100 no storage this winter, will have 500 gals. next). Western New York (coldest winter I can remember) . I dug 4' deep trench with small backhoe (soil is clay) . Lined bottom of trench with sand, layed logstor , then backfilled with clay. Price was 17 bucks a foot. As far as the pipe itself , I have been happy with the product, it was like wrestling an anacoda getting it in place, but has a durable shell casing , and although I can't give heat loss numbers (check their website) I have been happy with the performance this winter. We have had record lows this year, and feb was the coldest month on record of any in this area and I have had no problem keeping the house at 70 or better. The foam in trench may be a cheaper option , but the logstor made for a quick and easy install by one man without having to hire outside foamers. Bruce
 
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No hard data for you but I had a Foamer setup to do my lines and I bailed a week before. I just could not get past not having a water proof barrier around the foam. I went with the 32mm logstor. I buried it 6' down in all sand a few feet parallel to my water line. It comes up into heated space on both ends so I can travel in the winter and not have to find someone to baby sit the boiler. :)

gg
 
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I have thermopex last 8 years buried 4' down. Very hard to flex but no complaints. No measurable heat loss going 55'. I rented a trencher.
 
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I found for short runs costs were about the same between foaming a trench and buying the commercial foamed product if your foamer has a minimum charge. My run was 50'; I had a local foam outfit without a minimum charge so I went with the foam, I lined the trench with plastic, put down 2" pink insulation board, , foamed, put the pex into the foam as it expanded, then foamed again over the top. then wrapped the plastic around it and buried it about 4' down. Can't say yet how well it works as I haven't finished the install of the rest of the system yet.
 
No hard data for you but I had a Foamer setup to do my lines and I bailed a week before. I just could not get past not having a water proof barrier around the foam. I went with the 32mm logstor. I buried it 6' down in all sand a few feet parallel to my water line. It comes up into heated space on both ends so I can travel in the winter and not have to find someone to baby sit the boiler. :)

gg

+1 on that.
 
I have 50 feet of thermopex. Of which approximately 12 feet is exposed in my garage. whenever the boiler is running if I put my hand on the exposed thermopex I do not feel any heat.
 
In all respects the Thermopex and Logstor are very comparable, but the Logstor has a couple of slight advantages that give it the edge in thermal efficiency. 1) the gas barrier designed to maintain the integrity of the foam over time and 2) the smooth casing exposes less surface area to heat loss. It’s harder to work with, but it's more thermally efficient than the Thermopex with undulations.



That said, I still went with the 1.25" Thermopex because it's what I could find locally and that saved me a $500
freight bill.

75' run, back filled with what came out of the trench buried 4' down. I have analog gauges on each side and can't see any temp delta.

Do some research about the requirements for closed cell foam to be called "closed cell" - 80% is what I found. And all producers I asked specifically stated not for continuous contact with water or will deteriorate.
 
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I used thermopex 3' down. I wanted to get it below frost line but sometimes when the water table is up it may be in ground water. I don't notice any temp difference in my 75' to 80' run. I just back filled with the clay I dug out. ideally I would have put some sand in the bottom of trench.
 
I used 1 1/4 thermopex for approx 200 ft run (100 each way) burried about 3-4 feet in fine sand and backfilled with the same. It was the least expensive option in my area--foamers were priced real high and using pvc pipe or other conduit with wrap wasn't cheaper plus more labor. Not really seeing any significant heat loss in the thermopex.
 
I used EZ15ob from Badger Insulated Pipe, I bought it mostly because it was cheap compared to the alternatives, most people here will not recommend it because if you get water infiltration into the tile you're done, and the line is basically garbage. I have 240 ft buried roughly 4ft down, I back filled it the first few inches by hand to make sure no sharp rocks or anything hit the pipe. The entire line is more-or-less on a slope downhill from my boiler in the shop to the house which is built into the hillside. Three years in the ground so far and no water infiltration yet (pretty sure if there was any it would run into the house). No real noticeable heat drop from one end to the other, but my analog dials are probably not too accurate so I can't say how much exactly.
 
thermopex (CB 1.25) I stuck it inside yet another pipe, wit power ! IMG_0891.JPG
 
then I ran some more foam in a 2 legged "t pattern" (I placed another 2" foam on top) .....works good .... this is where its the shallowest ie solid rock under the 12" of dirt/gravel at this point of my pipe err the last 14' of it anyway! IMG_0905.JPG
 
I'm finally to a point I'm ready to order my under ground lines. I found a thermo pex dealer near me (well about 1 hour away) so I'll be going to pick up my section of thermo pex soon. I called them today to ask about pricing the guy told me he will be driving to a town even closer to me ( about 30 min.) And he said he could bring it up to me. So I thought that was pretty nice.
 
We use logstor. It's well worth it, and the ID is similar to 1" copper rather than 1" pex which gives favorable hydraulic performance. I do like the foamed in place option, but the long term moisture issue concerns me.
karl
 
It seems the financial cross over point for the "off the shelf" vs "foam in trench" method is in the 40'-60' range depending on local foaming rates. From following foaming in trench here over the years local foaming contractor rates varies dramatically. But for our ~170' run the cost difference was very significant (less than $1000 for the 170' trench). Our underground system has been in place for 6 years with no measurable change in energy loss between the boiler barn and the house. We recently added a water and data line to the barn and nicked the foam of our boiler line. The scrap of closed cell foam was dry. But, like I said, if our run had been ~50' we'd have used Thermo Pex or Logstor. Just a data point on how our foam in trench is holding up.
 
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