GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Central vac in an airtight home

Airfix | Posted in Mechanicals on

Just thought I’d run by the use of a central vac in an air tight home by the experts on this website.

I’m assuming because a central vacuum system draws air in from inside the air control layer and expels it into the mechanical room which is also inside the air control layer there are no issues with having a central vac in an air tight home.

New Build
Climate Zone 6A
Pretty Good House
Exterior Foam
Target 1.0 ACH

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. Expert Member

    Are you sure it doesn't exhaust to the outside? I've only installed a couple of them, but they both did.

  2. user-2310254 | | #2


    Ideally you would locate the motor unit in any outdoor room or garage. One reason to have a central vac is the ability to exhaust vac air to the outdoors. I don't know how good your vacuum bag might be, but I suspect it fails to trap a lot of nasty material.

  3. Airfix | | #3

    You know I'm not sure where it vents. My contractor has it as a line item on my budget (I'm sure my wife had something to do with that). I thought I'd better try figure out the technical details.

  4. GBA Editor
    Martin Holladay | | #4

    Steve Mackay,
    I'm going to disagree with Steve Knapp on this one.

    If you install a central vacuum cleaner, the ideal location for the dust collection bag is in the basement (or, in your case, in the mechanical room) -- that is, inside the home's conditioned envelope.

    If, instead, the dust collection bag is located in the garage, the house will be depressurized every time you run the vacuum cleaner, raising the possibility that any atmospherically vented combustion appliances (like a gas water heater) will backdraft.

    Some people like the idea of locating the dust collection bag in the garage. If you do that, it's important to remember to crack a window every time you vacuum.

  5. user-5574861 | | #5


    Google recirculating central vac, I saw a couple of manufacturers at IBS this year but I can't remember the names. The dust collection bag and exhaust are inside the thermal envelope. They use a HEPA filter on the exhaust. My old school central vac has the dust collection bag in the basement, but it exhausts to the outside. On a separate note, I liked the hide a hose feature they offer now. The hose retracts back into the tubing for storage.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |