I am about to lay a Loose Wire underfloor heating system, should I use primer?

The need to use primer when installing a loose wire underfloor heating system depends on whether a backer board is being used.

If the heating element is laid directly onto a plywood or concrete subfloor, primer should be used. If an insulation board is used, there is no need to use the primer as these boards are already primed.

The primer should be left to dry for 2-3 hours, until tacky, before laying the heating element .