thermal comfort
indoor environmental quality
residential heating design

General Solutions

For consumers or general interest
For the architect, engineer, contractor, wholesaler and manufacturer
For those interested in the business side of the industry

can't find what you're looking for - post your question online


How important is thermal comfort?

Have some fun! Play with Dr. Marsh and Caroline Raines Comfort Calculator. Place your cursor over the grey sliders to experiment with different values. (If the graphic does not appear you will need to download a free flash program from macromedia - click here) - Thermal Comfort Calculator Courtesy of www.squ1.com.


Be sure to check out our new student design validation software tools for radiant cooling and heating systems.


Discussion on the Thermal Comfort Modeler

What do the terms mean? (For a detailed overview on comfort click here)

Predicted Mean Vote(PMV) is a scale used by your interior environmental design professional (Environmental Ergonomists) to predict comfort. Ideal range is between -0.5 and +0.5 (Neutral).

Percentage of People Dissatisfied (PPD): If 85% of the occupants are satisfied (or 15% dissatisfied) with their interior environments, then the Building/HVAC system is generally considered acceptable. Some things like floor surface temperature, and stratification can influence comfort more than other metrics. Statistically over 50% of home owners are dissatisfied for one reason or another – but you can see why by using the comfort calculator.

Air Temperature is what an ordinary thermometer would measure. Did you notice what happened when you raised or lowered the air temperature. Temperature stratification also plays a role in local discomfort.

Radiant Temperature: At rest the human body exchanges between 50% and 60% of its heat via radiation. Notice the sensitivity of radiant on comfort. Also note the temperature you are controlling is not the surface temperature of a radiant floor for example but the Mean Radiant Temperature of the space. Learn more about radiant systems.

Relative Humidity is how dry or clammy you would feel. Think what happens to air after you have had a shower or if the air has been dehumidified by an air conditioner. (Learn More)

Air Velocity is how fast the air is moving through the room. Air can move naturally through convection or is forced by fans. What is the relationship between air temperature and air velocity - play with the indicators and find out. (
Learn More)

Activity Rate describes what you are doing ...afternoon nap, or playing tennis perhaps? (Learn More)

Clothing Level describes what you might be wearing while doing an activity.


Home | Seminars | Solutions | Heating Cafe | Contribute | Online Help | Bean's Blog | About Us | Glossary
Privacy Policy | Legal | Contact Us | Site Map |
Carlson-Holohan Award| Send Us Your Comments

Copyright © 2009 Healthy Heating. All rights reserved.
Site developed by WebworX.ca 
Donate using PayPal, Credit Cards Accepted  
Healthy Heating accepts Visa, Mastercard, Amex and Discover.