Understanding Insulation and R-Value | Ask This Old House

Summary

In this video, Tommy uses a dollhouse and an infrared camera to demonstrate how insulation works and its importance in managing heat loss. He explains the concept of R-value, which measures the resistance to heat transfer in insulation. Through the infrared camera, viewers can see where heat escapes in a house, such as through windows and roofs. Tommy also provides practical advice on measuring existing insulation in your attic and determining how much more insulation is needed based on your region's climate. The video is an engaging and informative guide to improving home insulation efficiency.

Takeaways

• 😀 The video demonstrates the use of an infrared camera to detect heat loss in a dollhouse, with heat represented by orange colors and cooler temperatures by blue.
• 😀 Windows show the most significant heat loss, with the left side of the dollhouse having the most heat escaping, while the right side remains well-insulated.
• 😀 Insulation helps reduce heat loss, and the effectiveness is measured by the 'R value,' which represents the resistance to heat transfer.
• 😀 R values vary depending on the region you live in: warmer climates require R30 for the roof, central regions need R38, and cold areas near Canada need R49.
• 😀 The largest heat loss in a house occurs through the roof, which is why adding insulation in the attic is crucial.
• 😀 To assess your attic's current insulation, measure the height of the insulation using a tape measure from the insulation's top to the top of the ceiling joists.
• 😀 Fiberglass batt insulation has an R-value of approximately 3.5 per inch, meaning a 3.5-inch batt has an R13 value.
• 😀 If you live in a colder region, you may need to add more insulation to your attic to meet the necessary R-value for that climate.
• 😀 Properly adding insulation to your home can significantly reduce energy costs by preventing heat from escaping.
• 😀 The video emphasizes the importance of understanding your home's current insulation and how much additional insulation you might need to achieve optimal energy efficiency.
• 😀 The use of an infrared camera allows for a visual representation of where insulation improvements should be made in the home.

Q & A

What is the purpose of using an infrared camera in the dollhouse?

The infrared camera is used to visually demonstrate heat loss in the dollhouse, showing which areas are losing the most heat, with warmer areas represented by orange and cooler areas by blue.

What do the orange and blue colors on the infrared camera represent?

The orange colors indicate warmer temperatures, where heat is present, and the blue colors indicate cooler areas, where heat is not escaping.

What does the term 'R value' refer to in insulation?

R value refers to the resistance of heat transfer through insulation. It measures how effectively the insulation prevents heat from escaping.

What factors should be considered when deciding how much insulation to add?

When adding insulation, you need to consider both the location of the insulation (e.g., attic or walls) and the region you live in, as climate plays a role in the amount of insulation required.

What is the primary area of heat loss in a house, and where should more insulation be added?

The primary area of heat loss is through the roof, so more insulation is typically added to the attic to prevent heat escape.

How do climate regions affect the required R value for insulation?

In warmer climates, the R value for the roof is typically R30, while in the middle of the country it's R38, and in colder regions, like near Canada, it is R49.

How do you measure the amount of insulation already in your attic?

To measure the insulation in your attic, use a tape measure to measure the height of the insulation from the top of the plaster or wallboard to determine its thickness.

What is the R value of fiberglass batt insulation with a height of 3.5 inches?

The R value of a fiberglass batt insulation with a height of 3.5 inches is R13, as the R value is calculated at 3.5 per inch.

Why is it harder to add insulation to walls compared to the attic?

It is harder to add insulation to walls because it requires more work and possibly structural changes, while the attic is more accessible and easier to insulate.

How can you use infrared technology to identify areas that need more insulation?

By using an infrared camera, you can see where heat is escaping, such as through poorly insulated walls or windows. These areas will appear as bright (orange) spots on the camera, indicating a need for additional insulation.