Copyright Goodheart-Willcox Co., Inc. 266 Hydronic Heating: Systems and Applications consult system manufacturers for the proper controls and peripheral devices that accompany this type of system. Most manufacturers of snow and ice melt systems provide information on such design criteria as type and size of piping to use, as well as the proper spacing of the tubing and correct zoning techniques. 12.8.3 Snow and Ice Melt Installation Although there are similarities between the installation of a snow and ice melt system to that of a radiant flooring system, there are differences that must be adhered to. Because the system is located outdoors, the installation criteria dif- fer as outlined in the following steps: 1. Remove existing walkway or driveway surface materials. 2. Be sure the earth grade is firmly packed—use sand or gravel as a base. 3. Install a minimum of R-5 insulation onto the finished grade. 4. Use rebar or woven wire fabric to strengthen the concrete base. 5. Staple the tubing to the insulation or use clips or ties to fasten the tubing to the rebar or wire fabric, Figure 12-52. 6. It is recommended that the tubing be placed 2″–3″ below the concrete surface for a faster response time. 7. If using interlocking pavers for a finished surface (such as for a sidewalk), encase the tubing in a 1 1/2″ sand bed. Pavers can then be installed over the sand bed. 8. If tubing is to be installed under an asphalt finish, it should be encased in a 3″ layer of stone dust or sand media and compacted. Note: Flush the tubing with cold water during asphalt installation and keep doing so until the asphalt has cooled. When designed and installed properly, snow and ice melt systems can provide years of trouble-free service. These systems can reassure homeowners and busi- ness owners that their sidewalks and driveways will remain free of snow and ice, making a safe and secure environment for their families, employees, and customers. City of Holland Figure 12-52. Just as with slab-type radiant floor systems, the tubing for snow melt systems must be securely fastened to the woven wire fabric.