New Home Construction with Wood Studs Framing Heating Cooling System Air Duct Works Plumbing and Electrical Ceiling Light Cans

ANSI 380 and What It Means For You!

There are some industry changes coming down the pipe stemming from RESNET’s adoption of the ANSI 380 Standard for Testing of Airtightness. If you’re looking for some light reading before bed, I encourage you to read the entire document. If you’d rather not, here is our two cents on what you can expect from the new standards.

Why the changes?

 The new standards are intended to establish national consistency for testing the air tightness of enclosures, HVAC distribution systems, and the airflow of mechanical ventilation systems.

Who will it impact?

This change will mainly impact the testing procedures of home energy raters, energy auditors and code officials but there is fall out that will impact builders.

What should I expect as a builder?

The good news is not much with one big exception:

When should I expect these changes to go into effect?

All homes permitted on or after July 1st, 2018 will be subject to the new ANSI 380 standards.

Don’t know if your strategy will be affected by these changes?

We do! You can expect SEM to reach out individually if you’ll be impacted.

Common Fresh Air Ventilation Strategies

To help you make educated decisions and find the right path forward, we’ve itemized out the three main fresh air ventilation strategies below with a brief break down of their pros/cons.  We also encourage you to contact your HVAC contractor to discuss these strategies as well.

01. Supply Only Ventilation - Brings air into the home

A dedicated duct supplies fresh air to the return side of the HVAC system​. Key to this strategy passing under the new ANSI 380 standards is that it has a mechanical damper installed on the fresh air duct to provide a proper airseal.

Pros for Supply Only Ventilation

Cons for Supply Only Ventilation

02. Exhaust Only Ventilation - Removes air from of the home

A bath exhaust is put on a smart switch programmed to automatically exhaust air at a set interval

Pros for Exhaust Only Ventilation

Cons for Exhaust Only Ventilation

03. Balanced Ventilation - Equal exchange of air into and out of the home

Using either a Energy Recovery Ventilator (ERV) or a Heat Recovery Ventilator (HRV), the balanced ventilation strategy provides a 1 to 1 exchange of air into and out of the home. An ERV is preferable in our climate zones due to the fact that it can remove moisture from incoming air in addition to exchanging heat.

Pros for Balanced Ventilation

Cons for Balanced Ventilation


Taylor Fearrington, Builder Services

Contact Taylor Fearrington at 919-454-6412

Or Request a Free Consultation