During renovation and insulation upgrade work: is it absolutely necessary to comply with current standards?

This is a question many homeowners ask themselves every year: "If I replace the insulation in the attic of a house built in 1979, am I required to meet the new energy efficiency standards required by the Code today?"

The response obtained from the Régie du bâtiment du Québec (RBQ) provides crucial insight for all those considering minor work.

What the regulations actually say

The RBQ first clarifies that the majority of provisions in Chapter I – Building of the Construction Code do not apply to existing single-family homes. However, one important exception remains: Part 11 of the 2015 NBC (Quebec Amendment), concerning energy efficiency , is applicable to all small residential buildings.

• Building area of 600 m² or less; • Height of 3 stories or less; • Residential use (group C).

But here's the key point : According to the official interpretation of the RBQ, Part 11 does not apply to the renovation of an existing building. It applies only to:

• To the construction of new buildings; • To extensions; • And only to the enlarged portion when the extension does not exceed 50% of the initial area of the building.

Therefore, simply partially renovating a wall, attic or basement that requires removing insulation or repairing damage does NOT trigger the obligation to bring the insulation up to current standards.

In practical terms, what does this mean for a homeowner?

If your work is minor and localized (e.g., replacing insulation on a section of the building, spot repairing a wall, restoration after damage), you can put back in place:

• An insulation equivalent to the original one; • With the same RSI (or R) factor.

Therefore, you are not required to meet the minimum insulation values required by the currently applicable Code.

Beware of municipal exceptions

Some municipalities may adopt stricter rules than those of the RBQ. It is therefore always recommended to check with the local urban planning department.

Conclusion for the owners

If your work only involves a one-off replacement of insulation and does not constitute an extension of the building:

• You can replace the insulation with insulation of the same value as the original; • You are not legally obligated to meet the new insulation standards; • Energy efficiency standards do not apply to simple renovations.

This clarification from the RBQ finally provides a definitive answer to a question that thousands of owners and contractors in Quebec have been asking.