House Pencil Drawing

What is Building Science?

Are you constantly feeling sick, too cold, too hot, or too dry? Does your house seem drafty?

Using building science, the study of air, heat, and moisture movement, Southern Home Performance looks at your house as a whole with a lot of different parts that work together. Building science includes the analysis of HVAC systems for both physical impacts (heat distribution, air velocities, relative humidities, etc.) and how it effects the comfort level of the building’s occupants.

House Pencil Drawing

We consider all the building blocks that are involved in the stability of your home environment.

These include:

  • The building assemblies: what the structure is made out of…the wood, insulation, concrete
  • The mechanical systems: what makes the house function…the heating system, air conditioning system, ductwork, venting, fireplaces / chimneys, plumbing system, bathrooms, hot water heater, electric, and major appliances
  • The air you are breathing
  • Your personal lifestyle… how much time you spend in your house and what do you do when your home.

These building blocks must interact effectively to create a stable environment where there is a balance between the flow of air, heat, and moisture.

Air Movement

Air always flows from a high to a low-pressure area like water running downhill. Without an effective barrier, air outside a home at a higher pressure will attempt to enter the home. Similarly, inside air at high pressure with reference to the outside will tend to exit the house. Air needs an opening or hole to flow through and a driving force to move it. Leakage into and out of a home depends on the pressure difference and hole size. We need air flow through our buildings but not through our structures.

Unintended holes in the structure or the ductwork allow uncontrolled air leakage and rob a home of its efficiency and healthful environment. Improper air flow can led to adverse effects on the health and safety of the people in the building by promoting mold growth, spreading pollutants, and possibly creating backdrafting of combustion appliances, causing possible carbon dioxide poisoning. It can draw in moist air from outside, or force moist interior air out into the walls, ceilings, and other structural assemblies affecting the house’s structural integrity.

Girl Sitting in Front of Portable Fan

Uncontrolled air flow is any non-designed movement of air into, out of, or within a building. This can be caused either by wind, by the force of heated air rising within the building, or by out-of-control fans.

We’re not talking about your portable house fans but the fans within your HVAC system.

Boys Sitting in Front of Fire Playing Cards

A wood-burning fire utilizes the three types of heat transfer that exist in nature and are known to physics. These include convection, which is a transfer of heat through air currents. Conduction is a transfer of heat through solid objects such as the ground or the bricks in a fireplace wall. Radiation is the third form of common heat transfer, and can include radiation from the light of the fire and the oxidation of the fuel in the process of combustion.

Heat Movement

There are three ways that heat flows throughout your house – Convection, Conduction, and radiation.

  • Conduction refers to the direct contact of two surfaces. The heat will transfer from the warmer surface to the colder surface until a balance is achieved.
  • Convection refers to the fact that as air increases in temperature, it expands and rises to the top of the room. This forces down the cooler air so that it becomes heated, thus creating a convection current.
  • Radiation refers to the fact that all objects radiate heat. This heat travels through the air to objects that are colder.

Improper heat movement can adversely affect your health as well as the structure and energy efficiency of your home. Mold and mildew can grow where surfaces are left cold and condensation can form. Heat can also collect or escape in places where the wrong insulation is used or is improperly installed, causing your HVAC unit to be overworked.

Get Your Springtime Air Conditioning Service Scheduled Today


Customer Preferred. Kindly Referred.

Moisture Movement

Water is everywhere. Controlling where the water goes is key to avoiding major impacts on occupant health and safety, comfort, building durability and energy efficiency.

Too much moisture can lead to excess mold and bacteria growth as well as a breeding ground for unwanted guests such as dust mites and cockroaches. Both problems trigger asthma and allergic reactions.

Boy Looking Out Window on Rainy Day

Windows and especially mulled window joints and window corners often leak rainwater into the wall.

Kids Playing Video Games While Parents Relax on Couch

Get A More Comfortable & Healthier Home Environment

As you can see, air, heat, and  moisture play a large part on your health and the efficiency and durability of your mechanical systems. Whether you have specific concerns about your home or you want to ensure your home is performing efficiently, Southern Home Performance wants to help. Call us today for a Whole Home Assessment & Energy Audit. We want to help you by making your home a more comfortable and healthier place to live.

Ready to Get Started?

Don’t hesitate to give us a call to schedule an appointment with one of our technicians.


Related Services

Attic Encapsulation >>


Whole Home Assessments & Energy Audits >>

Look Into

Whole-House Dehumidifiers >>