Install Instructions

IOM-WR-SH 1528 14 of 24
SPECIAL APPLICATIONS
STEP 3.9
Expansion Joints: 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 cable 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 Coverings
STEP 4.1
Before beginning work, inspect the cable for damage and secure any cable that may have
come loose.
To avoid burying any possible damage that may have occurred since the cable was laid,
the following tests should be performed:
Use a digital multi-meter to measure the resistance between the conductors of the cable
power leads again (see Step 2.3). Your electrician should perform an insulation resistance test
on the cable. A megohmeter (e.g. Megger
®
) adjusted to a minimum 1000 VDC should give a
measured value at least 20 megohm (MΩ). (see Step 1.4)
STEP 3.10
Wet Locations
Acceptance of this application must be verified by the local inspector or authority having
jurisdiction (AHJ).
• Never make a field splice to cables installed in a wet location.
•
Never begin the cable in a wet location. The connection between the power lead and the
heating cable must be fully embedded in concrete and located at least 1' (305 mm) away
from the wet area.
•
SlabHeat controls must be located at least 4' (13.1 m) away from shower openings. Controls
cannot be exposed to water or touched by a person while in a shower area.
Expansion Joint
Gravel
Heating Cable
Protected to prevent
concrete encasement
Sand
Concrete