SunTouch Mats Specifications and Installation Procedure
By SunTouch® A division of Watts Water Technologies, Inc.
Smile when you take off your shoes.
Overview 
SunTouch mats come in many different sizes and can be shaped and combined to warm almost any room.
- Fully grounded power leads and heating elements
- Twin-wire design engineered for ultra-low EMF levels
- REET tested for use in living areas
- GFCI protected controls
- Compatible with tile, stone, and masonry flooring
- Available in 120V and 240V systems
SunTouch is a safe and efficient electric floor warming system designed for interior applications only. It is intended for installation below tile, stone, and masonry flooring materials in residential and light commercial applications.
The SunTouch Mat
The heating wire is woven into a durable orange mesh mat available in 1 ft, 2 ft, and 3 ft widths for both 120 VAC and 240 VAC systems.
Mats range from 10 sq. ft. to 160 sq. ft. depending on size and voltage.
Multiple mats can be wired together in parallel to cover larger spaces, however all mats must use the same voltage.
Example: To heat an 80 sq. ft. area you may combine:
- Two 1' x 40' mats
- One 2' x 20' mat and one 1' x 40' mat
Never combine 120V and 240V mats together.
Heating Wire Construction
Enlarged cutaway view of the heating wire.
SunTouch heating wire features reinforced Aramid fibers and ETFE insulation with braided twin-wire shielding to reduce EMF exposure to ultra-low levels.
SunTouch systems have been tested according to ASTM C627 and rated for moderate commercial and residential applications.
Important: Never install SunTouch directly below vinyl, carpet, or wood flooring unless fully embedded in approved mortar materials.
Items Required for Installation
Main Components:
- SunTouch heating mat
- Floor sensing thermostat
- GFCI breaker
- SunStat relay (if required)
Additional Tools & Materials:
- SunTouch installation kit
- LoudMouth monitor
- Digital ohmmeter (multimeter)
- Thin-set mortar or self-leveling mortar
- Tile installation tools
- Electrical wiring and electrical box
- Stapler or hot glue gun
- Insulation if required
Read Before Installing SunTouch
- Never install under carpet, vinyl, or wood without mortar encapsulation
- Never cut or shorten the heating wire
- Never overlap heating mats
- Never install mats in walls
- Never install mats under cabinets or built-ins
- Always fully embed heating wire in mortar
- Always record resistance readings before, during, and after installation
- Always follow NEC and local electrical codes
- Always use copper conductors only
- Always seek professional assistance when needed
Inspect the Mat and Sensor
Throughout installation, resistance readings must be taken using a quality digital ohmmeter.
Readings should be taken:
- Before installation
- After fastening the mat to the floor
- After flooring installation is complete
The LoudMouth™ monitor helps continuously monitor the mat during installation and alerts installers immediately if wire damage occurs.
LoudMouth™ Installation Monitor
The LoudMouth monitor continuously checks the heating wire throughout the installation process. If the wire becomes damaged or cut, an audible alarm sounds immediately.
Using the LoudMouth helps prevent damaged wire from being buried beneath mortar and tile.
Mat and Sensor Resistance Log
Record all resistance readings to maintain warranty coverage.
| Measurement Stage | Required Readings |
| Before Installation | Black to White, Black to Green, White to Green, Sensor Wire |
| After Mat is Fastened | Black to White, Black to Green, White to Green, Sensor Wire |
| After Flooring Installation | Black to White, Black to Green, White to Green, Sensor Wire |
Retain all resistance logs for warranty purposes.
Checking for Breaks and Short Circuits
Checking for breaks:
- Measure resistance between black and white leads
- Reading should match nameplate specifications
- Infinite resistance indicates a break or open line
Checking for short circuits:
- Measure resistance between black and green leads
- Reading should show infinite resistance
- Any measurable resistance may indicate wire damage
Phase 1: Electrical Rough-In
Step 1.1: Install GFCI Protection
All SunTouch systems must be protected by a GFCI device either through the thermostat or a dedicated breaker.
Typical amperage requirements:
- 120V systems: 0.1 amps per sq. ft.
- 240V systems: 0.05 amps per sq. ft.
Step 1.2: Install SunStat Relay if Required
Systems exceeding thermostat amperage limits require a SunStat relay.
Step 1.3: Install Electrical Boxes
Install thermostat electrical boxes on interior walls approximately 60 inches above the floor.
Step 1.4: Bottom Plate Work
Drill openings for conduit and floor sensor routing directly below the thermostat location.
Step 1.5: Install Conduit and Floor Sensor
Install conduit as required by local code and route the thermostat floor sensor into the heated floor area.
Step 1.6: Rough-In Wiring
Install all electrical wiring according to NEC and local code requirements.
120 Volt Mat Amperage Requirements
| Mat Size | Coverage | Amp Draw |
| 1' x 10' | 10 sq. ft. | 1.0 |
| 1' x 20' | 20 sq. ft. | 2.0 |
| 2' x 20' | 40 sq. ft. | 4.0 |
| 2' x 40' | 80 sq. ft. | 8.0 |
| 3' x 15' | 45 sq. ft. | 4.5 |
240 Volt Mat Amperage Requirements
| Mat Size | Coverage | Amp Draw |
| 2' x 10' | 20 sq. ft. | 1.0 |
| 2' x 40' | 80 sq. ft. | 4.0 |
| 2' x 80' | 160 sq. ft. | 8.0 |
| 3' x 20' | 60 sq. ft. | 3.0 |
| 3' x 40' | 120 sq. ft. | 6.0 |
Phase 2: SunTouch Installation
Step 2.1: Select Installation Type
Approved installation methods:
- Thin-set mortar over framed floor
- Thin-set mortar over slab
- Thick-set mortar over metal lath
- Self-leveling mortar systems
Step 2.2: Floor Preparation
Subfloors must be clean, dry, structurally sound, and free of debris before installation begins.
Step 2.3: Review the Layout Plan
Carefully study the mat layout before installation. Never cut or shorten the heating wire.
Step 2.4: Mortar Applications
SunTouch may be installed using:
- Thin-set mortar beds
- Thick-set mortar beds
- Self-leveling mortar systems
For non-masonry floor coverings such as laminate or engineered wood, self-leveling mortar installations are recommended.
Step 2.5: Installing the Mat
Roll out the mat according to the installation plan and secure it using double-sided tape or staples.
- Keep mats 4"–6" from walls and fixtures
- Never allow heating wires closer than 2" to each other
- Never overlap mats
- Only cut the orange mesh, never the wire
Step 2.6: Shower Installations
- Never install mats in shower walls
- Controls must remain at least 4 feet away from shower openings
- Factory connections must remain embedded in mortar
- Only install beneath masonry surfaces
Step 2.7: Power Lead and Factory Connection Installation
Power leads and factory connections may require shallow recesses in the subfloor to maintain a flat tile surface.
Use hot glue to secure the leads and connections in position while avoiding damage to the heating wire.
Step 2.8: Thermostat Sensor Installation
The floor sensor should be positioned between heating wires approximately 6"–12" into the heated area.
Avoid placing sensors near heating ducts or other heat sources.
Step 2.9: Mat Turns and Fill-In Techniques
The orange mesh may be cut and rotated to navigate corners and obstacles while keeping the heating wire intact.
Phase 3: Final Floor Installation
Always continue resistance testing throughout the flooring installation process.
- Use latex-modified or epoxy-modified mortars
- Recommended trowel size: 3/8" x 1/4"
- Never strike the heating wire with a trowel
- Prevent nails or screws from penetrating heated areas
Phase 4: Final Wiring
Step 4.1: Install the Controls
Install the thermostat according to manufacturer instructions and connect all wiring in parallel.
- 120V systems: black-black, white-white, green-green
- 240V systems: black-black, blue-blue, green-green
All wiring must comply with NEC and local electrical codes.
Helpful Resources
- Shop SunTouch Floor Heating Systems
- Shop SunTouch Heating Mats
- EMF Electromagnetic Fields Information
- SunTouch Frequently Asked Questions
- How to Repair Damaged Heating Wire
- SunTouch Warranty Information
- SunTouch How to Video's
Important: We strongly recommend installation by a qualified electrician and professional tile contractor. Always follow TCNA, ANSI, NEC, and manufacturer installation guidelines.