Install Instructions

16
Expansion Joint
Gravel
Heating Cable
Protected to prevent
concrete encasement
Sand
Concrete
STEP 3.14
Expansion Joints: ProMelt heating cable must never be run through an expansion joint. Doing so may cause damage
to the cable with slab movement. It is recommended to lay the mat so these joints are avoided.
However, if it is necessary, a portion of the heating cable may be dropped into the grade below the expansion joint as
shown. Fill around the cable with at least 1 inch thick sand. The loop of heating cable should be long enough to allow
flexing, and must not be embedded into the concrete (the sand should protect against this) since this would not allow
the cable to flex with slab movement.
Phase 4: Finish Surfaces
STEP 4.1
Before beginning work, inspect the mat/cable for damage and secure any mat/cable that may have come loose.
To avoid burying any possible damage that may have occurred since the mat was laid, the following tests
should be performed:
Use a digital multi-meter to measure the resistance between the conductors of the mat/cable power leads again (see
Step 2.3). If possible, your electrician should perform an insulation resistance test on the mat/cable. A megohmeter
(e.g. Megger®) adjusted to a minimum 1000 VDC should give a measured value at least 20 megohm (MΩ).
CAUTION: Be prepared to install a marker plate or other identification indicating the presence of ProMelt in the slab.
This helps alert and avoid possible damage from future on-site. Install a marker plate where clearly visible in each
snow-melted area. A marker plate is placed flush in the wet concrete surface or soft asphalt surface. Other types of
surfaces should be made to allow the marker plate to be installed flush with the surface. Do not damage the heating
cable.