All ResourcesHeated Flooring
Heated Floor Installation: SunTouch Systems
8 min readBy Sundry Pro Shop
Why Radiant Floor Heat?
Warm floors aren't a luxury — in Montana, they're a quality-of-life upgrade your clients will thank you for. Radiant floor heating is efficient, silent, and eliminates cold tile shock in bathrooms, kitchens, and entryways. And it's more affordable than most contractors think.
SunTouch System Options
WarmWire (Most Versatile)
•What it is: A continuous heating cable on a spool with spacing guides
•Coverage: 20–140 sq ft kits
•Best for: Irregular-shaped rooms, custom layouts, bathrooms
•Spacing: Adjustable 2.5" or 3" spacing for different heat output
•Catalog options: multiple kit sizes are represented; confirm the exact kit against the current SunTouch plan and instructions
HeatMatrix Mats (Fastest Install)
•What it is: Pre-spaced heating cable bonded to a peel-and-stick mesh mat
•Best for: Rectangular rooms, straightforward layouts
•Install time: 50% faster than WarmWire — just roll it out
•Cutting: Cut the mesh (never the cable!) to turn corners
Cosy Floor Kits (DIY-Friendly)
•What it is: Complete starter kits with mat, thermostat, and installation materials
•Best for: Small bathrooms and powder rooms
•Includes: Heating mat + SunStat thermostat
Planning Your Installation
Sizing the System
1.Measure the heated area — exclude areas under vanities, toilets, and fixed cabinetry
2.Select your product based on the area and room shape
3.Add a thermostat — one thermostat controls one zone (up to 150 sq ft for WarmWire, check mat specs for HeatMatrix)
4.Plan the lead wire route — the cold lead must reach the thermostat location
Electrical Requirements
•Dedicated circuit — most systems require a dedicated 20A GFCI-protected circuit
•Thermostat location — install in a dual-gang box at a convenient wall location, 60" above the floor
•Code compliance — all connections must be made by a licensed electrician per NEC Article 424
•Wire gauge — check the system specs; runs over 100 ft may need heavier gauge
⚠️ Always have a licensed electrician make the final connections. The heating cable installation is the flooring installer's job; the electrical connection is not.
Step-by-Step Installation
Step 1: Prep the Subfloor
•Subfloor must be clean, flat, and structurally sound
•If using DITRA-HEAT, install the uncoupling mat first
•For traditional mortar-bed installations, apply a primer coat if needed
Step 2: Plan the Layout
•Sketch the cable/mat layout on paper first
•Keep cable 3" from walls, vanities, and fixtures
•Never overlap or cross heating cables
•Route the cold lead wire to the thermostat location through the subfloor or wall
Step 3: Install the Floor Sensor
•The floor sensor wire comes with your thermostat
•Route it from the thermostat box, through conduit in the wall, and into the floor
•Place the sensor between two heating cables, centered in the heated area
•The sensor must NOT touch or cross a heating cable
•Secure with hot glue or tape
Step 4: Install the Heating Cable/Mat
For WarmWire:
•Secure cable straps to the subfloor with screws or hot glue
•Weave the cable through the straps at your chosen spacing (2.5" or 3")
•Keep consistent spacing throughout
For HeatMatrix:
•Unroll the mat starting from the thermostat wall
•Peel and stick to the subfloor
•Cut the MESH (not the cable) to turn corners
•Press firmly for full adhesion
Step 5: Test Before You Cover
⚠️ This is the most important step.
•Ohm test: Use a multimeter to test cable resistance. Compare to the specification on the product label. It should be within 10%.
•Record the reading on the warranty card
•Test again after each subsequent step (after thinset, after tile)
•If the reading is open or zero, STOP — find and fix the damage before covering
Step 6: Embed in Thinset
•Apply modified thinset (Laticrete 254 Platinum or Uzin CX-20) over the cable/mat
•Use a ¼" × ¼" square-notch trowel
•Work carefully — do not nick or cut the cable with the trowel
•Fully encapsulate the cable — no air voids
•For self-leveling encapsulation, use Uzin NC 150F (fiber-reinforced)
Step 7: Install Tile
•Once the embedding coat has cured (24 hours), tile directly over it with modified thinset
•Normal tile installation from here — your substrate is the cured thinset over the heating system
Step 8: Final Electrical Connection
•Licensed electrician connects the cold lead and sensor wires to the thermostat
•Program the thermostat and test the system
•Do not energize the system until the thinset and grout have fully cured (typically 7–14 days)
Thermostat Options
SunStat Command
•Programmable 7-day thermostat
•Floor sensor + ambient air sensor
•Easy to program, large backlit display
SunStat Connect
•Wi-Fi enabled — control from your phone
•7-day programmable + smart home compatible
•Floor and ambient sensors included
The catalog also represents extra floor sensors. Confirm the exact sensor and installation method against current SunTouch instructions.
Common Mistakes
❌Cutting or nicking the heating cable (system failure)
❌Not testing ohms before, during, and after installation (no warranty)
❌Overlapping cables (hot spots, fire risk)
❌Placing cable under fixed objects (overheating)
❌Energizing before thinset/grout is fully cured (curing issues)
❌Forgetting the spare floor sensor (costly repair later)
Catalog Products to Review
•SunTouch WarmWire kits (20–140 sq ft)
•SunTouch HeatMatrix mats
•SunTouch Cosy Floor kits
•SunStat Command and Connect thermostats
•Extra floor sensors
•Laticrete 254 Platinum and Uzin CX-20 thinset for embedding
Stop by the Pro Desk — we'll size your system and get you everything you need for the job.
Continue planning this job
Use current manufacturer instructions as the authority, then confirm exact products, quantities, availability, and pickup timing with the Pro Desk.