Multi-Family HVAC System

10 Replies

I am in the midst of putting an offer on a multifamily house. I am wondering what everyone is doing in regards to HVAC systems. I am going to gut the house and redo it all, but I want to add HVAC. 

Is everyone putting in an air handler for each unit? 

It seems extremely costly if I were to run separate ductwork and supply and returns for each unit... can someone walk me through how they're making this work.



Is it a duplex?  It is best to have a separate HVAC system for each unit but if the multi family unit is all on one utility meter then you might want to get one of those ones where you can control the system from 2 different units.  

Good luck

It's a quadplex with separate gas meters, separate electric meters, and separate water heaters, and only one forced heating system. 

- Is there a more cost effective way to distribute heat and a/c to the units individually?

- If it MUST stay as one utility meter and I do have separate zones for the heating then how do I make the tenants pay for that fairly? (it seems to me I would get complaints that people are using more and some are using less)


This is a question for your local building department. Building permit(s) are required for installations subject to building code(s) and the installation will need to comply with the minimum requirements.

If forced air it has to be separate to each unit. 

The cheapest way would be electric baseboard heat and window units not ideal though. 

With an airhandler/furnace for each unit with ductwork your looking at 20k+. 

What year is the house?  How big are the units?  Have you considered looking into ductless?

In PA there are court rulings regarding foreign utility loads being billed to a tenant; see link:

So probably best to just split it all now. 

In the City of Philadelphia, you will also have to have an extra electric meter to serve common areas, such as lighting and fire alarms.

Since you are doing a gut, now would be the time to get the ductwork for both supplies and returns into place. And you will have to locate the air handlers, compressors, furnace and gas lines appropriately too. What is the arrangement of these four units (all stacked above each other, two on one level and two on another level, etc)?

Although PGW is expensive for gas, it's still cheaper than electric heat. 

The unit breakdown is 1 on the first, 2 on the second, 1 on the third.

If I run 4 supplies and one central return it might start eating into a lot of unit space. 

I budgeted about 20k for the material and labor. 

You would need FOUR returns, one for each unit. 

I'm guessing you have a common area hallway that you will have to heat in winter; that you would probably do with electric baseboard. But since you originally said each unit had a gas meter, then was there a fifth gas meter for the central furnace?

This is a really old building. There is oil for the one furnace now to heat the building. This building was abandoned but I assume the landlord included heat in the rent amount because it wasn't split up. As for the gas meters in the basement they are currently running just ranges and dryers no heat.

My goal is to convert to all gas and have individual units for each. If I must run ductless mini splits then they are heat pumps anyway on electric.

So the hot water heaters are electric?

Remember that heat pumps need a back up fuel when they are unable to extract adequate heat when outside temps drop too far.  Electric heat as back up gets expensive. 

Free eBook from BiggerPockets!

Ultimate Beginner's Guide Book Cover

Join BiggerPockets and get The Ultimate Beginner's Guide to Real Estate Investing for FREE - read by more than 100,000 people - AND get exclusive real estate investing tips, tricks and techniques delivered straight to your inbox twice weekly!

  • Actionable advice for getting started,
  • Discover the 10 Most Lucrative Real Estate Niches,
  • Learn how to get started with or without money,
  • Explore Real-Life Strategies for Building Wealth,
  • And a LOT more.

Lock We hate spam just as much as you

Create Lasting Wealth Through Real Estate

Join the millions of people achieving financial freedom through the power of real estate investing

Start here