Pex in a hot asphalt pour......anyone done it?

hot_rod

Back in nthe day we would back concrete trucks right over the rubber tube, when we did long driveways. Did funny things to the pressure gauge, but we never had a problem.

I'm not sure the current version allows trucks to be put on top, check with the Watts team first.

hot rod

Mad Dog_2

This DAMNED HOUSE!!!! continued

Ok, here goes: Finally getting around to the LAST vestige of the OLD house
(The original driveway circa 1960) Potholes and overall conditions are atrocious. Jimmy The Gent Burke and I attended Siggy's seminar about 2 years ago. He spoke of the future.....driveways that could be multi-use...he mentioned a solar driveway......
Cut to the chase: I AM doing this one way or another.
ME is working closely with me as a pet-research project. (I AM going to owe this man several steak dinners and bottles of Beaujolies from the many times he has come to my aid).

big QUESTION: has anyone poured asphalt directly onto PEX (water running thru it of course)?

I know what "They" saY blah blah. Me thinks the pex could handle it w/ out any actual melting of the tubing IF and only if we keep cold water ruuning thru during pour.

I think of me burning off pro-pex fittings with torch.....
8 0 0 - 1 0 00 degrees...and it STILL takes a while

We know what the manufacturer'd say....JUst want real life experience and advice. Thanks > mad dog

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Perry_3

I think it would create

the most interesting crack lines in the asphault in a couple of years... I am sure that the owners will be really impressed at that point.

Perry

Scram Bulleggs

Oil?

What would the petroleum do to the PEX over time?

Mad Dog!!!!!!!!

Crack lines?

From what exactly. This is MY house, so if it fails and just have the wife to deal with. Mad Dog

Troy_3

Asphalt on pex




Yes-I've done it a few times. The first time I was so nervous I put a piece in a wheel barrow and filled it with water and filled the wheel barrow with asphalt. After 10 minutes I pulled it out and No problem at all. The barrier was still intact. I have always run cold water through the lines while it is going down just as a precaution. The biggest **** is that the binder must be hand tamped. You obviously can't drive over the tubes with a roller until there is some support. Asphalt seems to really melt well. It soaks up solar energy real nice.

Mad Dog!!!!!!!!

Isn't PEX derived from a Petroleum type process?

Mad Dog

Mad Dog!!!!!!!!

This is exactly what I was hoping to hear

Eatherton and I had the gut feeling that this would be the best way to do it. I'm not even worried about losing the barrier because I will use a FP HX on it anyway. As long as tubing is not melted open. I was thinkinmg of burting the tubing in a slab THEN asphalt over that, but I think we will lose much of the heat transfer of the aspah;t when the heavy sun is out. What has to be hand-tamped? Mad Dog

Mad Dog!!!!!!!!

BTW

This will be used as solar only. Snowmelt is a luxury to me. Mad Dog

Troy_3

asphalt

Normally the asphalt is dropped from a truck to a spreader and then rolled. With tube in the way that process is out. Every asphalt I have done has been placed from truck to wheel barrow to tubes and then hand tamped. This is a flat plate on a pole that is rammed up and down to compact the asphalt tightly around the tubes. This is what they call binder. The binder is a larger aggregate mix of asphalt. Once the binder has been tamped good by hand and cooled, they run a roller over it. Then the topcoat can be spread normally and rolled.

Gordy

Asphalt operations


Hey Mad Dog, If the pex can handle the heat is one aspect the other would be the rolling of the asphalt,the paver, backing trucks upto the paver. Seems if you have an asphalt company in mind get in touch with them, and discuss what you want to do.

How much asphalt do you intend on laying? Usually drivways get 2" that basiclly translates to a 3" to 4" mat that gets rolled to a 2" finished product depends on the size of the roller they use. That will leave an 1 1/2" cover over pex.

Personally I'm a concrete kinda guy, but asphalt is the ticket for what you are trying to achieve. If I were to do asphalt I would go for a 4' finish product. I see how cars when parked in the same spot will actually leave divots in the driveway with a customary 2" mat. Alot of that is subbase being properly preped.

One thing to keep in mind would be to lay your pex longitudally to the drive, and maybe with some measurements of the tire tracks of the paver, and trucks you can avoid tracking on the pex. Dont know how big the drive is so maybe this wont be a big deal. Sometimes they can just get away with loading the paver hopper, and it will be enough to do a pass with out backing a truck in there.

One other thing Mat request surface for the Mix not a binder mix. If you look at some asphalt drives that look like they are gravel painted black that is a binder mix....Cheapest bidder. Surface has finer aggregates which will give you a smoother finish,and will last longer. Water is asphalts enemy. So a pourous surface will lend itself to trapping water more (Binder Mix).


Gordy

Paul Pollets

Question....

How would you know if the O2 barrier was compromised?

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

JJ_4

Petro-mat

Troy...on a resurface job at my facility they put down petro-mat (sp?). We have expansive clay soil (Colorado)and this was suggested by the contractor to help with cracking. We also have extreme temperature swings day to night.

Would this be good for Mad Dog between the binder layer and the top coat to minimize any future cracking since he is in Colorado also?

Uni R_2

Steel is real!

Matt, what about using ½" black iron?

Better transfer of heat, better resistance to high pressure loads (think of things like motorcycle kickstands on hot sunny summer days or the heavy truck that decides to use your driveway to turn around), easily tracable afterwards and immune to the hazards of the install.

In the old days it was bent and welded... not sure if it could just be twisted in. Might be worth considering under blacktop...

Josh_10

Just a thought.. Not trying to endorse this product but IPEX has 5 layer PEX with the O2 barrier sandwiched in the center. Perhaps this would be a good application for it?

Troy_3

Barrier

The evoh is on the exterior of the small sample piece that I tested in the wheel barrow. I pulled out the 3' piece of pex and the evoh appeared to still be intact. I can't tell about the tube in the drive. I am assuming it reacted similar to the sample since the drive tube had cold water running through it all during the asphalt placement.

Troy_3

Asphalt Pro-NOT

Sorry i'm not an asphalt pro. I only can tell you what i've experienced on past jobs. And i can think of three jobs that have been running from 3-5 seasons. I've never heard of this mat.

ScottMP

How about

Pex-Al-Pex ?/ Might be stronger, you won't burn off the oxygen barrier. You'll have a HX anyway for the glycol mix correct ??

I did snowmelt at my house and would love to reverse it for solar during the summer but it dos'nt get the sun enough

Nice project Dog, show us some pictures.

Scott



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

mikea23

mad dog

Mad dog
You are using solar I would'nt worry about the 02 barrier geting damaged. Even if the snow melt system was geting 02 into it you have no boiler to damage I think the only weak spot would be the circ and how often would it be on anyway,
So what if you need a new one every 7 years instead of every 8. I also wouldnt worry about petro base ashphalt cold poor ashphalt is also made this way and that works fine in snowmelt.

Mike A

Norton

I've done it

We did 6,000+ sq ft of snowmelt with wirsbo hepex at a hospital. The Paving guys did a "cold" lift. (Not sure what temp they considered cold.) We had 22,000+ ft of tubing and circulated tap water through the tubing throughout the paving process. It has been running for four years now with no failures, tubing or pavement.

Maine Doug_62

Would the

efficiency be improved and a little protection gained by using the aluminum plates I see on the Wall for joists? I would imagine that the more conductor in contact with sun heated asphalt would transfer heat to the pex??

[Deleted User]

Picture of Matts old driveway...

This is going to be a VERY interesting project :-)

ME

Mark_7

Driveway

Years back I think there was an article in fuel oil news of a radiant job under black top and they put the tubing in compacted grit than topped over that.

Gordy_2

Results

Yes Mark it will be. More interesting to me is the kinda Btuage Matt can get out of this reverse snowmelt type a system. I'm thinking of all the parking lots all over the world bakin in the sun that could be heating tons of water through a heat exchanger, for domestic use, pool heating. Charging "The Hole" for a ground source heat pump for in the winter.

Lots of people have mentioned the extra benifit gained by their snowmelt system doing this. Maybe its time to think outside the box, with the extra benifit being the snow melt in the winter if you choose.

Widen that driveway to the left Mad Dog, save yourself some yard work, and gain some more collector surface. A man can never have enough driveway.

Gordy

Mad Dog_2

I have been thinking of the parking lots

for the past few years as well. Hey, ALOT of peolpe I know think I am nuts for even Trying this. We'll prove them wrong. Mad Dog

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Mad Dog_2

Just what I had in mind Gordy

You can't see it, but the asphalt takes a right in the back yard. We will be restoring that area back to grass, so it is even swap. About 20 feet into the driveway, it will make a sharp left to the bushes. This is where I will keep the garbage cans (finally away from the house). The wife argued that it was wrong to take away the grass and that we didn't NEED a wider driveway....she didn't grow up in a house with a long skinny drive! Besides...I convinced her that we live on a street that - at certain times of the day is a speedway. Now the kiddies will have their own place to skate and play hockey and B- Ball. Mad Dog

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Gordy_2

No Parking

Wait, and see You will be parking in the street. All the kids on the block will be hanging at the smooth drive.

Lay this one on the Mrs. some sunny day. Honey would you mind parking in the street your cutting down on my Btu production, you can park in the drive at sunset.

That will get the deer in the head lights look for sure, or maybe some blackend head lights.

Gordy_2

No Parking

Wait, and see You will be parking in the street. All the kids on the block will be hanging at the smooth drive.

Lay this one on the Mrs. some sunny day. Honey would you mind parking in the street your cutting down on my Btu production, you can park in the drive at sunset.

That will get the deer in the head lights look for sure, or maybe some blackend head lights.

Keep us posted I have about 2600 sq.ft. of parking lot that will need asphalt soon looks about like your driveway now.

Gordy

Mad Dog!!!!!!!!

tHAT SOUNDS LIKE THE WAY

My paving contractor would like to do it. However, this will be for solar use and I am concerned about the tubing and its surrounding material being able to "grab" most of the btus thru the asphalt. Jimmy The Gent Burke has a few out there (solar) where the tubing is buried in 2" of concrete refine (recycled and finely crushed concerete)then 2" of black top. He extracting 130-140 on a good sunny day. My only concern with only 2" of base is weight bearing capacity. My contractor expressed concern about that too. Poured concrete base is gonna cost me more AND I am concerned that unless I pull it high during the lift, like 1" below top of sub slab, that it will be too far down to grab the btus that the asphalt is absorbing. I don't know how deep down the heat will migrate. I know hot (the aspahlt) goes to cold (the ground below)in theory, but we are talking solar here and cycles of the sun, i.e., by the time the heat penetrates in to the sub slab w/ tubing, the sun may be going down. Mad Dog

Darin Cook_5

Dog

When we toured the HTP factory, one of their parking areas had onix under the asphalt. It seems to be working for them. I was told they circulated cold water threw it during the "pour".









Darin

Donny

pre wethead

While still searching for somthing I liked to do that I could get paid for, I worked for a blacktop co, based on the picture of your drive, you have a very unstable base under your existing drive. I would recommend you ask your contractor to remove the proposed footprint of the new drive to a minimum of -10" put down fabric to keep dirt / mud from "pumping up" into stone sub-base then, a min of 6" of 2" compacted crusher run stone, followed by 2-1/2" of #2 binder topped by 1-1/2" fine ac top. Hope you will post construction pic's and results, once bldg. trades are in your blood you can't help stopping to look, see, ask, "what's it going to be"

Metro Man

colored concrete

How about having the concrete colored to a darker color. would imagine that a dark red would give decent heat absorption. Try NREL for different color testing on collector surfaces.

Never really liked asphalt for drives....... does the dippity do da 1st hot day a big truck pulls in.