Reposted from i.e., the Center for Energy and Environment's Innovation Exchange blog -- http://mncee.org/Innovation-Exchange/ie/

 

Even though the walls of an apartment look solid, air buoyancy and pressure differences between interior spaces cause air to move between rooms and even to other units in the building. And as it travels within a building, air pollutants such as secondhand smoke (SHS) can find their way from one unit to another. Stack, wind, and exhaust fan effects are all interior air driving forces that affect the migration of SHS within a multifamily apartment building.

In winter, for instance, the heated air inside the building has a lower density than the colder outside air. Think about a hot air balloon: warm air rises. Because of its buoyancy, the warm indoor air tends to rise and escape out of the top of the building. This air movement draws cold outside air in through the lower part of the building. Watch the Winter Stack Effect animation below to see how as the interior air rises, SHS migrates with it from lower to upper apartment units.



In summer, the opposite airflow occurs. The conditioned indoor air is cooler and denser, and therefore tends to flow towards the lower half of the building. Warm outside air is drawn into the upper half of the building. As you can see in the Summer Stack Effect visualization below, the interior air movement entrains SHS from higher to lower units.



Whatever the temperature, when air flows from a high pressure area to a lower pressure area, it creates wind. And when wind impinges on a building, the interior air tends to flow from the windward side to the leeward side, i.e. from high pressure to low pressure. Our Wind Effect animation shows how air carries SHS as wind pushes it from one unit to an adjoining unit.



In addition to the weather, mechanical factors can affect indoor air movement. In the next animation, you can watch as an exhaust fan sucks air out of a room, mechanically lowering its pressure. This create a pressure difference between the room and its surrounding areas. Since air flows from high pressure to low pressure spaces, air from the adjoining rooms is drawn into the room where the exhaust fan is running. Our final visualization shows how the Exhaust Fan Effect can entrain SHS from an adjoining unit below.



We hope that our animations will improve your understanding of the air driving forces in buildings and how they affect secondhand smoke transfer between apartments. Feel free to link to or embed these videos from this blog post, our resource page, or our YouTube site.

The motion graphics animations were designed and produced by Huma Saqib.

Related posts:
> 1,000 Words: Combi System Animations

Indoor Air Quality and Energy Efficiency: Part 1

Views: 342

Comment

You need to be a member of Home Energy Pros Forum to add comments!

Join Home Energy Pros Forum

Latest Activity

Reginald posted a discussion

For Sale Minneapolis Blower Door Test Equipment With DG 1000 New $1800

The Minneapolis Blower Door has long been recognized as one of the best designed and supported…See More
5 hours ago
Chuck Kurnik is now a member of Home Energy Pros Forum
9 hours ago
Rob replied to Tray Biasiolli's discussion Two-stage furnace, control at furnace or thermostat?
"I installed/configured a couple Honeywell VisionPro 8k models recently in a commercial facility. It…"
10 hours ago
Ryan T De La Rosa posted a blog post

Updating Guest Bathroom With Energy Efficient Options

Undergoing a renovation in search of energy efficiency would chill some people to the bone. Not us,…See More
12 hours ago
Jim Gunshinan's blog post was featured
12 hours ago
Mick Lane replied to Tray Biasiolli's discussion Two-stage furnace, control at furnace or thermostat?
"I was playing with a 2 stage carrier furnace last week.  The staging is not bad on the…"
14 hours ago
Veronica Pembleton posted a blog post
18 hours ago
Geoff Aldridge liked Eric Sperline's discussion Floor insulation attachment
22 hours ago
Jim Gunshinan posted a blog post
yesterday
John Proctor replied to Tray Biasiolli's discussion Two-stage furnace, control at furnace or thermostat?
"Ted -- The startup losses on modern furnaces are much smaller than the old days. I would suggest a…"
yesterday
Profile IconVeronica Pembleton, Thom Phillips and jeff greenberg joined Home Energy Pros Forum
yesterday
Barbara Smith's video was featured

RESEARCH RESULTS: Improving installation/maintenance practices

We conducted research on residential heating and cooling systems in Minnesota homes to help improve installation and maintenance practices for furnaces, air ... Seventhwave
yesterday
Jim Gunshinan's blog post was featured

Using God Talk—or Not—to Help the Planet?

I am always impressed with the work of Susan Shelton and the Shelton Group. So an email message…See More
yesterday
Jenna Bader's event was featured
Thumbnail

Zero Net Energy Virtual Conference, Jan. 25 & 26, 2018 at Online Webinar via Zoom, Facebook Live, and YouTube Live

January 25, 2018 to January 26, 2018
Devoted to the All-Electric, Solar-Powered Building TypeA FREE On-Line Conference using Zoom: …See More
yesterday
jeff greenberg replied to mark avila's discussion Aeroseal Homeseal Pro unit for sale?
"Mark: My client has one for sale. very lightly used but huge discount.   Where are you…"
Sunday
Jenna Bader posted events
Friday
Sean Lintow Sr replied to mark avila's discussion Aeroseal Homeseal Pro unit for sale?
"As I recall you have to be a Aeroseal listed "distributor" aka installer to get the…"
Friday
Paul Raymer posted an event

Radon Protections in New Homes at On line

January 30, 2018 from 1pm to 2pm
Radon-resistant construction is becoming a focal point in the high performance building industry.…See More
Thursday
mark avila posted a discussion

Aeroseal Homeseal Pro unit for sale?

Hello,We may be in the market to purchase a used machine should someone have one for sale.Cordially,See More
Thursday
Robert Zockoff liked Tray Biasiolli's discussion Two-stage furnace, control at furnace or thermostat?
Thursday

Photos

  • Add Photos
  • View All

© 2018   Created by Home Performance Coalition (HPC)   Powered by

Badges  |  Report an Issue  |  Terms of Service