Building Science 101
Using Building Science Principles
Hometrust takes a whole-house approach to home remodeling and improvements. Our visit to your home includes several steps of investigation and testing to properly diagnose and uncover potential issues in order to recommend energy efficient improvements that will work.
One of the most important building science principles that should guide home improvement decisions is the stack effect.
As seen in this figure, warm air rises in a home. This concept is not new. What is important to know is that the warm air that rises, if left unchecked, leaves the house through the gaps in the ceiling. What gaps you ask? That is what home performance is all about! Uncontrolled air leakage occurs when air moves through gaps or openings in walls, floors, ceilings, duct work, doors or windows and is often a major source of energy loss in homes.
As the warm air leaves the building, outside air is pulled in to replace the air that escapes. This is a physics phenomenon. The term stack effect comes from this dynamic that happens in the residential building, much like the characteristics of a chimney that while in use billows smoke at the top while the fire pulls oxygen in down at the base.
This pressure dynamic is what wreaks winter time havoc on energy bills and comfort and it also hampers summer indoor conditions as well.
The typical leakage points in a ceiling are fans, vents, light fixtures, plumbing holes, floors, walls, ceiling & the foundation. These are all things that are hiding in plain sight!
Stack Effect - Full View
The stack effect conveys your conditioned air out of the house when left to its own devices. Exfiltration points, as seen to the right, are opportunities to stop the conveyor belt and improve comfort and overall energy efficiency.
Attic Exfiltration Points
1. Plumbing vent bypass
Building Performance Institute
BGE Approved Energy Contractor
Pepco Approved Energy Contractor
Having your home evaluated by Hometrust is a great way to identify your next home improvement project.
Certifications earned through the Building Performance Institute demonstrate our ability to:
- Find air leakage points around your home.
- Show you steps to improve energy efficiency.
- Use science to guide improvements to comfort.
- Educate you how to tighten your building's shell.
- Learn about these opportunties before it is too late.
- Provide a unique perspective on your home's overall performance.
- Determine the root cause of any problems.
- Assess current insulation effectiveness.
- Measure air flow.
- Evaluate windows, doors, siding and roofing.
- Put you in complete control of the outcome.