Snow melt in three dimensions
High-end residences in ski resort communities can put snow-melt system designers and installers to the ultimate test. The challenges they pose are nothing new for Harris-Dudley Co., a fourth-generation family business that has served the Salt Lake City and Park City areas of Utah for more than 80 years.
Bob Dudley, president of Harris-Dudley Co., shared his insights on the snow-melt market in Utah and detailed a challenging project that showcased the strengths of his company: expert workmanship and creative problem solving. “Our great strength is our people,” he says. “Our versatility allows us to do all the aspects of the mechanical — plumbing, HVAC, snow melt and radiant — and we’ve gotten a lot of projects because of that fact.”
Educating builders and homeowners in the Salt Lake City Valley about the benefits of radiant heating and snow-melt systems can take some time, Dudley notes, but in the ski resort areas of Park City, the systems are viewed as a necessity. “We are talking ski-in, ski-out resort houses,” he says. “The realtors and architects let people know that in these areas, you have to have radiant heat and you have to have snow-melt systems. They extend the life of the driveway and help protect the property’s resale value.”
Dudley has found that preconstruction meetings can be essential, especially with high-end custom homes. “We’ve done some very complex projects for some very interesting people,” he said. “Sometimes those meetings are hard to get, but the homeowners might have unachievable expectations. The meetings allow us to determine their expectations, come to a common ground about what is realistic and make sure everyone is on the same page.”
Good things in small packages
For the Park City project, Harris-Dudley (www.harrisdudley.com) supplied the heating, cooling, humidification and snow-melt systems. During the design and bidding phase, the company typically identifies the areas that need snow melt. In this case, they included a driveway and decks comprised of concrete pavers as well as poured, stamped and colored concrete.
“The square footage is really the design basis for everything,” Dudley says. “It tells you how much tubing you’ll need in the driveway and decks, which tells you how many sets of manifolds or supplies and returns you’ll need. It also tells you the total amount of Btu you need, and from there you can determine the size of the boilers and how many you are using.”
There is one thing to remember in the bidding phase, Dudley notes. “We know that snow-melt systems almost always grow; they never shrink. You hope things don’t drastically change, but in the back of your mind you plan some escape routes in case they do.”
In this case, square footage was added to the snow-melt system for a total of 7,450 sq. ft. of driveway and deck space, but the toughest challenge was the removal of mechanical space from the architect’s plans. This left only a 7-ft.-by-10-ft. area in the garage for the equipment. The space was further restricted because the homeowners did not want to lose the scenic view from the garage window, which would have been blocked by floor-mounted boilers.
“Our mechanical space got taken away from us, but the advantage on this job was the fact that we could wall-mount 1.5 million Btu between three boilers,” Dudley says. “We were lucky that Viessmann had started to produce these very compact, higher-output, wall-mounted boilers because we used every available square inch.” The three Viessmann boilers were installed were two Vitodens 200 B2HA 150s and one Vitodens 200 B2HA 112.
Harris-Dudley finds it’s much easier and more efficient to prefabricate the piping rather than constructing it on site. “We have two guys dedicated to fabricating work in the shop,” Dudley says. “Our shop is fully stocked and you’re working under ideal conditions. It saves a ton of time and allows us to be more compact with our systems.”
The key to making the best use of available space is to think in three dimensions. “When you see some competitors’ jobs, you can see they are thinking in one single plane and their systems are very spread out,” he says. “With our systems, you’ll see piping stacked upon piping stacked upon piping, but it’s laid out so there’s nothing you can’t get to that needs to be serviced.”
That expertise was essential on this project. “The wall is jam-packed with systems, but you can still access them,” Dudley says.
The nearly 12,000 ft. of 3/4-in. ViegaPEX barrier tubing for the snow-melt system was installed near the end of construction. The company makes sure all lines will function perfectly before the concrete and pavers are installed. “By code, we pressure-test the tube system to 100 psi before the pour,” he says. “We keep air pressure on it during the pour, bumping it down per the manufacturer’s specifications. You have air on it, so you know that once the concrete is poured, then you’re good.”
A sensor that is level with the top of the slab detects temperature and moisture, and operates the system automatically. “In our area, the slab sensor is required by code,” Dudley notes. Placement of the sensor is crucial. “You don’t want it in an area where drips from the rain gutters are going to hit it, for example, and it’s also got to be in a spot where the snow is going to fall on it,” he says. “Typically we set them outside of the traffic area so a moving car doesn’t put a wet tire track over it and cause the system to kick on.”
The ultimate goal of a snow-melt system is to keep the driveway completely dry. “The reason you do that is so you don’t end up with ice in the expansion joints,” he says. “That’s why driveways last so much longer with a snow-melt system; you’re eliminating the freeze-thaw cycle on the concrete.”
Building on experience
Distinctive piping arrangements such as the one that allowed the company to squeeze the boilers into the tight quarters on this project have become the hallmark of a Harris-Dudley project. “Our piping is part of our brand,” Dudley says. “When you go out in the field, there might be variations on a theme, but you can tell it’s one of our jobs. Maybe the number of zones changes or, on the radiant side, maybe one project is a zone valve job vs. a pump job, but we’ve done these types of jobs over and over. We’ve figured out the best combinations of things for each job. We all know what the project is expected to look like.”
Systems also are designed with service requirements in mind. “When our service techs show up at the site, they don’t have to reinvent the wheel,” Dudley says. “They know how things function, they understand how our piping goes together, so there’s no big mystery in trying to track things down. And our service techs complete the feedback loop, reporting back to the fabricators, so if things need to be improved, we can stay on top of it.”
One area the company stresses is proper labeling of parts and systems. “The label maker is always on the job,” Dudley says. “You know which set of supplies and returns service each area of the snow-melt, and you know what zone activates which part of the house on the heating system. It’s the simple stuff that can make a big difference.”
The company’s versatility allows it to bid multiple scopes of work on projects, but it has other advantages as well. When mechanical rooms are tight, it can help when the plumber and HVAC installer are from the same company. “These guys have to work together. They see each other every day,” Dudley says. “There’s a lot more coordination and synergy. They watch out for each other.”
That type of coordination results in successful projects, Dudley notes. “All these jobs are team efforts,” he says. “Every one of the guys and gals in the field and in the office is an important part of the team. There might be five or six individuals out on a job, but every project is a team effort on behalf of the entire company.”
Have you worked on hydronic snow-melt projects? Tell us about your experiences in the comments section below!
Christopher K. King is an editor and writer who has covered the construction industry for more than 15 years. He previously served as associate editor of Plumbing & Mechanical, managing editor of the Air Conditioning, Heating & Refrigeration News, and editor of Roofing Contractor. He can be reached at firstname.lastname@example.org.