Why HVAC Experts Care About Insulation—And How AC Maintenance Protects Your Savings

Why do heating and air conditioning companies write so much about insulation? Isn’t it outside of their business model? Most AC technicians do not install insulation, so why share this information?

1. Insulation creates a thermal barrier to hold conditioned air (heated, cooled, filtered, dehumidified air) inside. If the conditioned air leaks out, it costs YOU money, but US reputation.
2. Insulation either makes the system work properly or makes it work much harder than necessary.
3. Insulation directly affects human comfort.

Since insulation affects our product and labor, we try to make homeowners as informed as possible.

Beyond the Unit: How Proper Insulation and AC Maintenance Lower Your Energy Bills

Imagine your home as a container holding water instead of air. The water would try to escape through every weakness, gap, and opening it could find; the outside of the home is called a building envelope, so the analog is very appropriate. In addition, a network of pipes runs around, under, and above your envelope to circulate the water (air).  Now, consider the strength of your container to keep the water (conditioned air) inside.

The Walls

Few construction methods fully address the building envelope/container model. Here are the strengths and weaknesses of walls as they relate to thermal barrier/building envelope.

• Stick framing leaves lots of very small gaps that allow air and thermal movement. Weather resistant barriers were introduced in the 1950s but became common building standards in the ‘80s and ‘90s. This barrier restricts moisture and air movement through stick wall structures.
• Wall insulation is graded by R-value (resistance). Four-inch walls will be rated R-11 to R-13, while six-inch wall construction will be rated R-19 to R-21. Anomalies that affect total insulation value are ductwork installed in outdoor walls.
• South-facing walls bear the most heat. Protecting these walls with tall shrubs or the shade of trees can reduce thermal gain.
• Approximately 25 to 35% of heat loss happens through the walls.

Since these walls are enclosed, there is very little that can be done to improve their insulation value unless spaces are remodeled or a room added to the space.

Windows and Doors

Glass conducts heat very well, so the R-value for windows is very low.

• Single-pane windows usually have a rating of R-1
• Double-pane and triple-pane windows have ratings of R-5 and R-8 respectively.
• Windows and doors create many opportunities for gaps. Caulking and weatherstripping can fill large gaps.
• Windows and doors also allow solar gain, heat from sunlight entering the home. Solar gain can add 100 from sunlight alone. Invest in good, insulated drapes or blinds.
• Approximately 25 to 40% of heat loss happens through windows and doors.

Ductwork

Duct material and installation various from home to home.

• Uninsulated ducts are made of joined pieces of sheet metal with lots of connectors and fasteners. The air inside is under pressure, so each gap allows conditioned air to escape.
• Often ducts run through unconditioned spaces, such as the attic, walls, crawlspaces, or garages.
• Approximately 20 to 30% of heat is loss happens through ductwork.

Since 50% or more of ducts are enclosed, there is little that can be done to improve seal ducts. Make sure that ductwork installed in attic spaces are completely covered in insulation. Improve duct insulation and sealing during remodels and home additions.

Attics

Most attics are the only space that can be accessed in order to add R-value, so it is mentioned the most often. Building code in this area call for a minimum of R-38, at least 12” of insulation for most products.

• Heat rises, so attic insulation is especially important during the heating cycle. However,
• Attic temperature during the summertime in Texas will range from 1300 to 1500 Fahrenheit during the day. Attic insulation slows the radiating of this heat into the house during the summer.
• Approximately 25% of heat loss happens through the attic.

Protect Your Investment with Professional AC Maintenance

Even the best insulation can’t keep your home comfortable if your cooling system is struggling to run efficiently. Scheduling regular AC maintenance ensures your system runs smoothly, lowers your monthly energy bills, and prevents costly unexpected breakdowns. Call  Northwind Air Conditioning and Heating right now at 713-683-9474 to book your AC maintenance appointment and keep your home cool all season long!