



It depends on the component, but you should replace the heat tape system and can probably reuse the snow retention.
Heat Tape is commonly damaged or past its lifespan when reroofing. Some lower end constant wattage cables only last 3-4 years, these should absolutely be replaced. Higher end self-regulating heat cables can last 20-30 years. A cable installed within the past 0-7 years is a great candidate for re-install, older cables will require additional evaluation. To determine whether or not a self-regulating cable can be reused, the cable should be assed for any visible damage to the exterior insulation and have a megameter test conducted to determine if there are any internal damages. Re-installing damaged or old heat tape can result in fire hazards. Use brand new clips or attachments for the heat tape system as old clips can lose their bit. Re-roofing is the best time to install new high end self-regulating heat tape as these systems typically last the lifetime of the roof.
Snow Retention entirely depends on the type installed. S-5! or TRA Sun and Snow systems, for instance, are often built and designed for the lifetime of the roof (metal roofs). These systems can absolutely be re-installed (unless there is some kind of underlying damage to the system of course). If these systems were installed with penetrating fasteners, these fasteners should be replaced if the retention itself will be reused. Glue on or adhesive based snow retention systems should not be reused. "Z style" (often called "Hardy Rib Snow Rail") should not be reused.
Yes. TRA Snow & Sun individual brackets are both designed and engineered for installation on top of and under asphalt shingles, wood shakes, and tile roofs. During a reroof or new construction, the brackets are integrated seamlessly into the roofing workflow: the long flat metal strap is fastened directly to the roof deck or underlayment, and the subsequent course of shingles is laid right over, leaving only the durable, power coated braked face exposed to catch the snow. While these individual brackets can also be retrofitted under the existing shingles, it is more challenging and if not done right, can lead to leaking problems down the line. It's best to install this system as a new rood is being installed.