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WarmWire • 35 Square Foot Radiant Floor Heating Cable (120V)

SKU# 120035WB-CST

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WarmWire is an affordable alternative to floor heating mats.

The constant diameter of their radiant heating cables makes securement into uncoupling membrane quick and easy!

  • Compatible for install into CableStrap or Floor Membrane at
    2 ½, 3, or 3 ½ inch spacing
  • Total design freedom allows for installation around turns & obstructions such as a toilet  or kitchen island
  • Covered by a 25-year manufacturer warranty whether installed with CableStrap or another manufacturers’ membranes
  • Approved for shower installation where permitted by the local authority having jurisdiction (AHJ)

WarmWire works wonderfully under natural stone, tile, laminate, engineered woods, carpet, vinyl, linoleum, & solid hardwood
(if you use sleepers).

Installation Demo

Instructions + Video

Instructions + Video

Instruction Manual
Install Steps

Step 1:

Plan your layout and determine the cable direction. Measure

about 3" in. inches from the wall, and place strap parallel to

the wall. Under toe kick spaces, install the strap 1.5"in. inches

to 2" in. inches away from the vanity.


Step 2:

Cut the strap to length for each side of area

to be heated. 




Step 3:

Secure the strap to the subfloor using double-sided

tape, glue, or fasteners.





Step 4:

Fill in each section back and forth with cable,

spacing the wire 2.5" or 3" in. inches

apart. For additional areas, cut and attach the

straps accordingly and begin weaving the 

wire into that area.




If cables are running greater than 3' or 4'ft. feet across a room, be sure to add another

strap to thread through in the center of the area to be heated.

Skill Level Running Cable more difficult + more time than MATS. Installation only by qualified persons. Electrician recommended for wiring. Read More
GFCI / GFEP Protection Required for each circuit. Built-in to all SunTouch SunStats.
Power Supply & Wiring
Mats or WireSupply WireBreaker
VACtotal amps(AWG*)qtytyperating
120up to 12 amps141single pole15 or 20 A
120up to 15 amps121single pole
20 A
240up to 12 amps141double pole15 or 20 A
240up to 15 amps121double pole20 A

* Recommended only. Follow local codes for wire gauge size.

Maximum Circuit Load 15 Amps
Maximum Circuit Overload Protection 20 A Breaker.
Electrical Box Size Extra-deep single-gang box for 1 or 2 leads, Or 4" square deep box for 3 cables (extra room needed for Wire, wire nuts, control)
Full Length End-to-End ground wire Yes.
Wire Construction Blue Flexible Polyurethane WaterProof Jacket surrounding 2 ETFE insulated copper heating wires, metal jacket & ground wire drain
Repair Information Yes, Wire can be repaired. Repair kits and assistance available.
Shower Installation Yes, can be installed in a tiled shower. UL listed, verify local code.
Layout Flexibilty No - example in manual. We provide Layout Maps only for MATS
Expected Floor Temperature This is dependent on many factors. A well-insulated floor can ensure better performance.
Insulation Recommended Yes; under slabs or framed floors. Cork or similar on top of Concrete Subfloor as thermal break
Indoor/Outdoor? INTERIOR floor heating application only. Embedded in mortar or self leveler only
Acceptable Sub-Floors on TOP of Sub Floor (Plywood, backer board, concrete)
Distance from Toilet Install 4 - 6 inches away; can be under front of toilet. Approx 20" from wall
Trowel Size recommended Minimum 3/8" x 1/4". Dependent on tile size - verify with tile/mortar manufacturer
Trowel type Recommended Heavy Duty Plastic PRO-Trowel
Cut Warning Never cut the heating elements to shorten
Minimum Install Temperature 50° Degrees F / 10° Degrees C


UPC 840213195199
Voltage 120 VAC
Cable Length 137 ' ft. feet
Cable Length (inches) 1644" in. inch
Cable Length (meters) 41.8m meter metre
Wattage per SF 12
Heating Power Output per Hour (BTU) 41 BTU per Sq Ft/Hour @ 3" in. inch spacing
Heating Power Output Total 1435 BTU total
Manufacturer Watts Radiant
Power Lead Type Armored, NEC color code, Single point connection at 1 corner of mat. No return wire like inferior products
Power Lead Length 10 Feet
Power Lead Wire Gauge 18 AWG
Thickness .110" - .132" (nominal) Shorter cables are thinner.
Spacing of Heating Wire 2.5" - 3" - 3.5" on center
Minimum Bend Radius 1/2" 0.50 inch
Resistance Value 29-37
EMF (Electro Magnetic Field) Yes. Verified by Independent Testing Laboratory as ultra low.
Thermostat Control Required? SunStat Floor sensing thermostat
Conduit Required? Conduit is not required for Power Leads
More Details

More Details

What's In The Box WarmWire Spool in Easy to dispense box. Detailed Installation Manual. Installation video online.
Brand Name WarmWire
Warranty 25 year warranty backed by USA Manufacturer since 1873
Why Helps

WarmWire = Zero EMF

Electromagnetic fields (EMF) are generated by all electrical devices, and the possible dangers of exposure to EMF are still the subject of debate and scientific research. Out of concern for their customers' safety, SunTouch created the first EMF-canceling electric radiant floor heating system in 1993, and to this day they only manufacture and sell floor heating systems that use their patented EMF-canceling design. We provide this EMF information because it is important to some people, not to frighten you or exaggerate any risk like others do. We simply aim to inform you and leave the choice up to you after explaining what we know. Read More Here.

Heated Area Size Covered 35
Amp Draw 3.5
Total Watts 420 watts
Custom Size Options None. Standard lengths only. No customization
Safety Listing UL (Underwriters Laboratory) Listed for U.S. and Canada under UL 1673 and CAN/CSA C22.2 No. 130-03, File No. E185866
Cable strap or guides 1 recommended (1 for every 40 - 50 sq ft)
BTUs/SF/Hr 1 49
BTUs/SF/Hr 2 41
BTUs/SF/Hr 3 35
Spacing between runs 1 2.5
Spacing between runs 2 3
Spacing between runs 3 3.5
Watts Per SF 1 14.4
Watts Per SF 2 12
Watts Per SF 3 10.3
Heated SF 1 29
Heated SF 2 35
Heated SF 3 42
Acceptable Floor Coverings Natural Stone,Tile, Laminate, Engineered Woods, Carpet, Vinyl, Linoleum, Solid Hardwood (if you use sleepers)

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Write Your Own Review

  • 100% worth the investment

    My husband and dad installed the WarmWire system with the HeatMatrix membrane in our new master bathroom and it was not only easy, but now we have a very comfortable bath experience.

    I would recommend piecing out the parts versus buying a kit.

    Posted on February 8, 2018 by Megan

  • worked as expected

    I gave my dimensions to Warm Your Floor and described the application of in a basement on a slab. They adjusted the spacing and it fit perfectly.

    Posted on April 9, 2017 by Ken

  • Excellent

    Installed and powered up and everything is working good. Used the Ditra mat for heating cable and the installation was extra easy and straight forward.

    Posted on May 19, 2016 by RonE

  • Floor works great!! Excellent product.

    Floor works great!! Excellent product.

    Posted on April 18, 2016 by Paul P

View All Reviews

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