The Electric Floor Heating industry uses many terms that may not make sense to those unfamiliar with the industry. While contractors may be more familiar with certain terms and know them like the back of their hand, homeowners may be unfamiliar. Below we’ve compiled a quick list of industry terms to help homeowners understand the industry a little better.
UNCOUPLING MEMBRANE – a product, typically in a sheet format, that is installed in between the subfloor and the flooring material. Because the uncoupling membrane separates the two layers of the flooring construction, any lateral movement in the subfloor below, such as expansion/contraction of the plywood subfloor, will not transfer to the tile layer above the uncoupling membrane. By absorbing this lateral movement, the uncoupling membrane reduces the risk of tile and grout cracking.
LOW PROFILE – thin or low height. With electric floor heating systems, low profile products such as Nuheat Mats are desired because its installation does not significantly increase the thickness or height of the finished floor.
COLD SPOTS – cold/unheated areas of the floor that are expected to be heated. Cold spots are caused by the installer not placing the heating wires of the floor heating system in the desired area or spacing the heating wires too far apart. Cold spots are a result of the installer not ensuring proper and even coverage when installing the floor heating system.
HOT SPOTS – overheated areas of the floor. Opposite from cold spots, hot spots are caused by the installer placing the heating wires of the floor heating system too close together or overlapping the heating wire. Hot spots can cause premature deterioration of the heating wire and is caused by improper installation techniques.
COLD LEAD – the portion of the floor heating system that connects to the thermostat. The cold lead is run up behind the drywall usually in plastic/metal conduit and connects to the junction box where the thermostat is located. The cold lead portion does not produce any heat thereby making it safe to be run behind the drywall. The cold lead is sometimes run along the subfloor in order to reach the thermostat location. The best cold leads are durable yet thin and flexible to allow installers to run the cold lead along the subfloor without affecting the overall buildup/height of the floor.
SPLICE CONNECTION -the connection point between the cold lead and heating wire/portion of the floor heating system.
FLOOR COVERING – also known as flooring surface.
SUBFLOOR – the flat surface on which all other layers rest. Subfloor is the bottom-most layer of the flooring assembly and is attached to the joists that form the house’s structure/frame. Typically made of plywood or OSB and ranging in thickness from 19/32” to 1 1/8” thick, the subfloor is the structural part of the floor on which everything lays. In concrete slab applications, the concrete slab IS the subfloor.
SUBSTRATE – the surface/layer on which the floor covering is installed on. The substrate could be the subfloor but tile is often not set directly onto the subfloor due to risk of subfloor movement which could cause the tile layer to crack.
THINSET – an adhesive primarily made up of cement and sand and commonly used to attach tile or stone to the substrate.
SELF-LEVELER (also known as “self levelling compound”) – a cementitious compound similar to thinset but with a runny consistency. Self-leveler is typically used to create a flat and smooth surface with a compressive strength similar to or higher than that of traditional concrete prior to installing interior floor coverings.
ROBINSON FLOOR TEST RATING – a test used to measure the ability of a flooring or substrate material/product to handle dynamic loads and weights.
Robinson Floor Test: http://www.tileusa.com/Articles/HerestoyouMrRobinson_Griese09.pdf