WarmlyYours Snow Melting & Slab Heating - Manual (Page 7)

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5.3 INSTALLATION UNDER ASPHALT
1. Ensure that paving contractor has a solid base of 4” to 8” (102 mm to 203 mm) of
crushed rock aggregate tamped down and ready to receive the asphalt.
2. It is extremely important that the paving installer does NOT use any heavy
equipment, machinery, or vehicles over the exposed Heating Cable. Any tracked
mechanical spreaders or dump trucks must be prohibited from running over
exposed Heating Cable.
3. During this process of laying asphalt, installing the heating product, and
laying more asphalt, it is the responsibility of the electrician to use a 500 VDC
megohmmeter and a multi-meter to continuously check the Heating Cables that
are being worked on top of, to ensure they have not been damaged.
4a. The paving installer should lay down the binder / base coat of asphalt and roller it
smooth. The paving installer must decide if this binder coat of asphalt is allowed
to cool before finishing with the top coat of asphalt. This should be coordinated
with the installer of the Heating Cable or Mats. When working on top of hot
asphalt, please consider pre-making “wire mesh heating Mats”. This means
rolling out the reinforcing wire mesh (provided by electrician) and pre-attaching
the Heating Cable to it using wire ties (like rebar wire ties) that will not melt from
the hot asphalt. These “wire mesh heating Mats” could be left in the yard next
to the driveway while the first binder coat is poured. While the asphalt is still hot,
two people could carry / drag each “wire mesh heating mat” over the hot asphalt,
have it flipped over so that it is wire-side-down / mesh-side-up, and then staked
down to the hot binder coat (stakes provided by electrician).
4b. If the paving installer decides to let the binder / base coat of asphalt cool prior
to finishing with the top coat, then wire mesh is only needed for free-form type
Heating Cable installations. WarmlyYours Snow Melting Mats may be staked
down to the binder coat without using any wire mesh (stakes may only pierce the
black plastic mesh, and should never make direct contact with the Heating Cable
itself). Again, it’s recommended that the Snow Melting Mat be laid down so it
is wire-side-down / mesh-side-up, to help protect it from damage by shovels.
When installing free-form type Heating Cable, stake wire mesh down to the
binder / base coat first, and then attach the Heating Cable to it using wire ties.
This means it is wire-side-up / mesh-side-down, so extra care must be taken by
the paving installer to avoid damaging the Heating Cables with shovels or rakes
used to spread the top coat of asphalt.
5. Once the heater cables are in place, the electrician must route the cold lead(s),
(20 ft (6.1m) provided per each Mat / Cable) through rigid metal conduit(s) to get
back to an accessible weatherproof junction box(s). The electrician may supply
junction boxes which can be accessed from above, so the rest of the box is
buried to avoid damage by lawn mowers and/or vehicles. Care must be taken by
the electrician so that none of the heated section of Cable enters the conduit(s).
If a slab-mounted snow sensor will be used, this is the best time for placement.
It should be located in an open area, away from trees or bushes, so that snow
will easily fall directly on it. Separate conduit should be used to protect the low
voltage sensor wire and must NOT be shared with any high voltage cold lead
from the Heating Cables / Mats.
6 . Once the Heating Cables and conduits are in place, and are attached by the
above methods listed, the final top coat of asphalt may be poured. At least
2” (51mm) of material must cover the Heating Cable. The paving installer will
be required to spread this around evenly with shovels and rakes. Shovels
should be duct taped so the blade ends are less sharp. Again, the topping coat
should be spread manually to avoid use of heavy machinery. The only time it is
acceptable to use a mechanical asphalt spreader would be when it can straddle
tire track coverage used for longer sloped driveways. Tire track coverage allows
the spreader machine to be used without it ever making any direct contact with
the Heating Cables.
7. Once the top coat of asphalt is spread over the Heating Cables evenly with at
least 2” (51 mm) thick coverage, it may be rolled over with the steam roller to
finish / flatten the driveway. Again, each Heating Cable / Mat must be tested
with a multi-meter and 500 VDC megohmmeter to verify that they have not been
damaged, and to ensure they will be ready for activation (final test) after the
asphalt has cured. These values should be recorded on the warranty card on
page 22.