Large road snowmelt project (questions)

Rob Blair

I am currently looking at a project for a road leading to a coal mine in southwestern PA.  Road is 3000' x 25'.  They want to do asphalt.  Man in charge talks about Vail, CO and how their streets are heated.

How are they constructed?  Are they concrete? 

Of course it would nice to have efficiency with this project, but overall I do not think that is a huge concern.  Bottom dollar gas prices.

Any information would be appreciated.

Thanks,



Rob Blair

Mark Eatherton

Don't do what they did in Vail....

The Vail system was originally tube in sand covered with pavers. They used a bubble foil bubble insulation that failed miserably, and caused shifting, and possibly settling of the sand, and subsequent moving of the pavers, and exposure of the tubing at certain points. Large sections had to be dug up and redone. I think it ended up in litigation.



The installation was performed by R&H Mechanical from up there in the Vail Valley. I understand that it is a district heating system, with the physical plant being centrally located, and distribution run from there to points of use.



Matt Carr with Dahl Denver would probably be an excellent resource because I am fairly certain that he provided the majority of the materials used, and is quite close with R&H. Matt can be reached at 303-744-3423.



Personally, nothing beats good old tube in concrete, with or without insulation below. Insulation below could be a real issue for you if they are running large pieces of equipment on it. Also, based on my recent experiences up in the mountains, horizontal movement (think continental drift) could cause issues with the tubing. My suggestion would be to allow for this movement by doing the deep whoopty do with the tubing similar to what is used for sawed expansion joints.



Sounds like an interesting project for sure. Hope they've got a deep/strong pocket book...



ME

Rob Blair

I figured I would here from you Mark

I figured that it would not have insulation.  I have my tubing manufacturer doing a budget design currently.  Thinking about 3-4 separate boiler stations, lodged in a small shed.   May do tubing embedded in stone dust then approximately 8 inches of asphalt.  I haven't talked with them about concrete yet.



Thanks,



rob

meplumber

Snowmelt.

We did a huge area of parking lot and pedestrian entrance on the north side of a hospital.



The engineer had originally spec'd foam insulation under the asphalt, but the civil guy was concerned about shifting of the asphalt due to the steep grade in a couple of areas.



We wound up tying the tubing to wire mesh and then the asphalt contractor laid the first lift "cold". I don't remember the temp. We ran cooling water through the pex during the entire asphalt set. There is no insulation under the snowmelt, most of it is sitting directly on ledge.



The system has been in operation for 10 years and they love it.



I cannot speak to efficiency. The facility was sitting on a large amount of excess steam capacity due to mechanical system upgrades and they actually welcomed the increased load to decrease short cycling.



Let us know how it works out.



Good Luck.

Rob Blair

Where was this job located?

PS:  Looked the jobsite over today.  Pretty steep.  They figure by next year they will have +- 500 vehicles a day using this.

Looking at doing 7 remote boiler stations, with each section being 500 feet long.

Thanks,

Rob