Snowmelt systems and heated driveways in northern Utah

A boiler heats a mix of water and antifreeze, and pumps push it through tubing buried under the surface. The surface warms to just above freezing, and snow melts as it lands.

The parts are:

• The boiler. A dedicated boiler, or the house boiler through a heat exchanger.
• The antifreeze mix. Propylene glycol keeps the tubing from freezing when the system is off.
• The tubing. PEX loops set in concrete, under asphalt, or in the sand bed under pavers.
• The manifold. It feeds the loops and sits in a box or in the mechanical room.
• The controls. A sensor reads temperature and moisture and starts the system when snow falls.
• Insulation and drainage. Insulation under the slab sends the heat up. Drains carry the meltwater away before it can refreeze.

Not without replacing the surface. The tubing has to sit under or inside the concrete, asphalt, or pavers, so an existing driveway has to come out first.

That makes timing the main question.

• New construction. The tubing goes in before the first pour. This is the simplest case.
• Driveway replacement. If the concrete is cracked or settling and due to be replaced, that is the time to add snowmelt.
• Pavers. Pavers can be lifted, the tubing set in the bed below, and the pavers laid again.
• Small areas. Steps, a front walk, or a short ramp can be rebuilt with tubing even when the driveway stays.

Call us while the project is still on paper. We need to agree on tubing depth, insulation, and drains with the concrete or paver crew before they start.

Heat the places where ice causes trouble. You do not have to heat everything.

• Full coverage. The whole surface stays clear. It needs the largest boiler and uses the most fuel.
• Tire tracks. Two heated strips carry the car up the driveway. Snow stays between and beside them.
• Steep sections. Heating only the slope keeps cars from sliding where it matters.
• Shaded and north-facing areas. These spots hold ice long after the rest has cleared.
• Walks, steps, and entries. These are small areas that prevent the most falls.

The heated area sets the size of the boiler, so this choice drives the rest of the design. Plan where the meltwater goes as well. Water that runs off a heated strip onto cold pavement refreezes there.

Snowmelt is built together with the concrete or paver crew, in this order.

1. Design. We size the system from the heated area, the elevation, the winter temperatures, and how fast you want the surface cleared.
2. Base and insulation. The base is compacted, and insulation goes down where the design calls for it.
3. Tubing. We fasten the loops to the mesh or reinforcing steel at an even spacing and run them to the manifold.
4. Pressure test. The tubing stays under pressure during the pour, so any damage shows on the gauge right away.
5. Surface. The crew pours the concrete or lays the pavers.
6. Mechanical work. We install the boiler, pumps, and heat exchanger, and fill the system with antifreeze.
7. Controls. We mount the snow sensor, set the controls, and test the system.

We give free estimates. Two kinds of cost matter: what it takes to build and what it takes to run.

The cost to build depends on:

• Heated area. More area means more tubing, more antifreeze, and a larger boiler.
• The boiler. A dedicated boiler adds cost. Sharing the house boiler needs spare capacity and a heat exchanger.
• The surface. Concrete, asphalt, and pavers are built differently.
• Distance. A long run from the mechanical room to the driveway adds piping.
• Controls. An automatic sensor costs more than a manual switch.
• Demolition. Removing an old driveway is its own job.

The cost to run depends on the fuel, the heated area, the controls, and the winter. The concrete or paver work is priced by that trade. Financing is available.

Have it checked every fall, before the first storm. Enbridge Gas tells customers to have natural gas appliances inspected annually by a qualified, licensed heating contractor, and a snowmelt boiler is one of them.

A fall service covers:

• The antifreeze. We test its freeze protection and its condition. Old antifreeze turns acidic and attacks metal parts.
• The boiler. We test combustion and clean the burner and heat exchanger.
• Pressure. A system that has lost pressure over the summer has a leak to find.
• Pumps and valves. They sit idle for months and can stick.
• The snow sensor. We clean it and test that it starts the system.

Run the system once before you need it. Finding a failed pump in October is far better than finding it in a storm.

It does when it is designed for the site. The Park City weather station sits at about 6,900 feet, and its normal January low is 15.6°F. Two things follow from that.

First, gas boilers put out less heat at high elevation. We size the boiler from the manufacturer's high-elevation ratings, not the number on the box.

Second, cold and wind pull heat off the surface. A system sized for a mild valley winter will fall behind in a mountain storm.

Controls make up much of the difference. A system that idles keeps the slab warm between storms and starts melting sooner. A system that starts cold needs time to warm the slab first.

Even a well-designed system can fall behind during the heaviest snowfall. It catches up and clears the surface after the snow eases.