The federal rating system, explained without the acronyms.
ERS stands for EnerGuide Rating System. It is Natural Resources Canada's standard method for rating how much energy a house uses, and it is the only rating in Canada that government and utility programmes treat as evidence.
Three things have to be true for a rating to count. It has to be produced by a registered energy advisor who has passed NRCan's examinations. That advisor has to be affiliated with a licensed Service Organization — the licence, not the individual, is what issues the label. And it has to be modelled in HOT2000 from measured inputs, not estimated.
EnerSolution holds that licence. Our Organization Licence Number is 9E, and it is the reason a file we produce is accepted where an ordinary home inspection is not.
What the rating gives you is a number in gigajoules per year for the whole house, comparable to any other rated house in the country, plus a modelled breakdown of where the energy goes. It is the closest thing Canadian housing has to a fuel consumption figure for a car, and it is increasingly what a buyer asks for.
An EnerGuide rating and label issued under a licensed Service Organization.
Anyone who has been told they need "an ERS", "an EnerGuide", or "a pre-retrofit evaluation" and wants to know what is actually being asked for.