Airflow specification and documentation

[MacLaddy]

Hello:

I have a few buildings I need to evaluate for proper fresh and total air changes per hour. Is there a common or codified "place" that I can look for the original engineered numbers? There are general room by room CFM balance for each grill on the drawings, but nothing that speaks to how much fresh air is being provided. Is there a document I'm missing that is typically included?

Thank you,
Mac

 

[EnergyProfessional]

The original construction documents should show that. also documents from retrofits since original construction.

You may be able to get that from the JHA, but i assume they purge data after some years. Obviously the owner should have that documentation.

 

[GT-EGR]

This isn’t a direct answer to your question, but I’ve found the outside air fraction very elusive over the years. If you are looking for code, you’d need the install year, that ventilation code, and you’d also need the original floor plan it was based upon to find the initial design targets.

That being said, if you are trying to evaluate the ventilation and total airflow - you should recalculate to the current layout and code (or better than depending on what your client goal is) and then get a test and balance contractor to take the real outside air and total airflow measurements associated with the unit. Then compare the two.

 

[MacLaddy]

Thank you both for the responses. I was able to get what I needed from that.