The Radiant Edge HotSlot™ Roof Ice Melt System


The Patent-Pending HotSlot is at the top of its class for energy efficiency and lowest in-place cost. It provides affordable protection for projects on a limited budget. It helps prevent ice formations at eaves and damage to structures and gutter systems. HotSlot’s one-piece, one-size-fits-all eave ice melt system is ideal for virtually all existing composition shingle and most metal roofs. Its commercial quality, baked-on finish provides years of excellent weather and UV resistance.

Regardless of roof slope or fascia angles, HotSlot’s smart design simplifies everything.

Click here to Learn the many Ways HotSlot Beats the Competition

It fits around most existing gutters and the heating system can be extended to gutters and downspouts. The heavy, highly conductive aluminum alloy eliminates the waviness (“oil-canning”) common with competing lightweight sheet metal systems. There are no unsightly fascia fasteners and the heater cable and slot are completely hidden from view. All these features ensure a rich, elegant, architectural finish.

The UL-rated heating system uses self-regulating heater cable technology that distributes heat only where and when it is needed. The hidden slot adheres to the NEC’s Section 426 allowing cable insertion, inspection, and replacement in the unlikely event of damage or failure. Systems may be operated manually or with an automatic controller. HotSlot’s engineered profile strictly follows the 4 Rules of Thermodynamics, ensuring the most energy-efficient design possible.

For commercial needs and heavy snow environments where maximum performance is desired, we recommend our more robust Radiant Edge PRO or Radiant Edge LT.

HotSlot, the workhorse that provides the economy and performance you need. Protecting your property with an advanced roof ice melt system has never been easier or more affordable.

Click Here For HotSlot’s QuickStart Install Guide

HotSlot at 5 degrees-346x257

HotSlot performing at 5°F.

HS Al-4-800

At the heart of HotSlot is a self-regulating heater which is surrounded with a massive, highly conductive aluminum alloy. Shown here with the Medium Bronze factory finish.


HotSlot is EASY. It’s installed directly onto most existing shingle and metal roofs with little or no preparation needed. There is no clamping, no drilling, nor special bending needed. The pre-drilled 8’ lengths are easy to handle and install. With composition shingle roofs, the top flange tucks under upper shingles, With metal roofing, HotSlot is simply inserted under the roofing panel. Matching waterproof screws effortlessly secure the system in place.

The heater cable is then inserted into a tight slot in the rear of the drip edge. This no-air-gap slot provides superior heat conduction from the cable to the massive panel and integral drip edge. Combine HotSlot with the Radiant Edge Valley for complete protection. Control options include manual operation and our 4CDC digital controller.

HotSlot is easily installed onto composition shingle roofs.



  • For prevention of eave ice formations
  • 50% of the heater output of the Radiant Edge PRO
  • Suitable for composition shingle and metal roofs
  • Slopes 2/12 and greater


  • Ten (10) year warranty on the HotSlot Panel
  • Ten (10) year warranty on the heater cable
  • See warranty for complete details

Power Output

  • 12 watts/foot

Self-Regulating Heat Cable Provided:

  • UL Listed, CSA Certified, and FM Approved
  • 1 run per panel
  • Model S1 for 110 Volt system
  • Model S2 for 208, 240, and 277 Volt systems

Panel Finish

  • High-grade factory baked-on paint finish
  • Dark Bronze finish
  • Medium Bronze finish

Panel Lengths

  • Standard is 8′
  • System is available in 4′ increments

Supplied Components

  • HotSlot Panel pre-bored with 0.22″ holes at 22.5″ O.C., 5 holes per 8′ length
  • 5′ Power Lead
  • Industrial quality self-regulating heater cable (1 LF of 12 watt/foot cable per foot of Panel


  • S1 or S2 Self-regulating heater cable for gutters, and downspouts
  • Matching pre-painted ultra low-profile waterproof screws with T-25 Torx drive
  • Power connection and splice kits
  • 4CDC 4- 30A circuit digital ambient temperature controller

Click Here For a Printable PDF Data Sheet

Click Here For HotSlot’s QuickStart Install Guide

Click Here For Use with Composition Shingle Roofing Detail #320

Click Here For Use with Existing Metal Roofing Detail #340

Click Here For Additional Technical Info and Downloads

Learn How The System Works

Learn How to Get Your Radiant Edge System

Learn How the System Is Controlled

Learn What Snow Classification Your Project Is In[/vc_column_text][/vc_column][/vc_row]