Building Sciene Series #3
2024-01-26
Source: Build Science 101 - Episode 3
Comfort and Health
Humidity should never get to elevated humidity levels (60% indoors)
Tuning of the building
- essential to understand the equations to reach the correct level of equipment example: 70k BTU vs 17k BTU of heating/cooling required for the house
BTU - British thermal unit 1 BTU ~ 1 Match worth of Energy 1 Ton = 12k BTU for a 1000sqft space
"Dilution is not the Solution to Indoor Pollution" - Joseph Lstiburek
Materials have different off-gassing periods. Some materials, such as Oil-based paints and spray-foam off-gases, quickly.
However, other products, such as Vinyl flooring, are off-gas for the product's lifetime.
Material carried into the house via the shoes can be just as important as the stuff coming on via the filter.
Always design an entryway where people can take off their shoes!
MERV higher = better filtration; at least 11 to 13 is recommended! MERV 15 is close to HEPA quality and is used in hospitals for filtration.
A high level of control and filtration don't need many operatable windows in a building with excellent airtightness. Always ask if this window really needs to be operable.
Summary:
Control:
- Build a really good envelope
- Size the equipment properly
- Install and Commission properly
Health:
- Things we build with
- Things we bring into the house
- Things that piggy-back on us when getting into the house
