Different energy programs have different standards/targets for airtightness. They are expressed in air changes per hour (ACH). For most programs there are different standards if the home is detached or attached. It is usually higher for an attached home because there will normally be penetrations and leaks between the adjacent units/houses

R-2000 , ENERGY STAR®, NetZero/NetZeroReady, and Novoclimat all have a minimum ACH requirement that needs to be met to obtain certification. Although ERS does not have a pass or fail ACH requirement, it is recommended that the builder aims for an ACH of 2.5 or less for detached homes and 3.0 or less for attached homes. If a new detached home is insulated and sealed as required by code, getting an ACH of 1.5 or less is easily attainable.

In the past it was common for insulators to ask if a builder wanted a "regular or code seal" or an "R-2000 seal." By now it should be obvious that if you seal your home to the requirements of the building code you should be obtaining an R-2000 seal. Therefore there is no longer any reason to ask, or be told which type of seal the client requires, as this is already dictated by the building codes.