What is R-Value?
June 18, 2020 4:13 pm
What is R-Value and why is it important to you?
The R in R-Value stands for resistance – thermal resistance. R-value is essentially insulation power. When we are talking in terms of construction and existing buildings, we are talking about how well a barrier, such as a ceiling, window, wall, or a layer of insulation, will resist the flow of heat transfer. Yes! They all have a bit of an R-Value! The higher the number of the R-Value, the better the prevention of heat transmission or loss.
For example, most heat is lost in-ceiling and attic spaces so higher numbers are used here. Lower values are usually used in walls as they do not account for as much heat transmitted.
Needs Vary Based On Climate
In the southern states, the standard use for ceiling and attic spaces would be insulation with an R-Value of 30. R-30 means 30 times the resistance compared to having no insulation at all. It gets colder in the mid-Northern states so the standard converts to R-38, and in the top Northern states they opt for R-49.
The higher the R-Value, the thicker the insulation is. You can go as high as you want if you allow for it in new construction or adding on. In existing structures, you are likely to be limited to what will fit, especially within the walls. Ceilings and attics have more room to work with.
How does it work?
Heat is transmitted through the walls and ceilings by conduction and radiation. Traditional insulation stops conductive loss with the pockets of air seated in between the layers. The individual fibers absorb and reradiate the heat. In order to get the full benefits of your insulation’s R-Value, it is important that it is installed correctly and not crammed into a smaller space than it’s intended for, split over wires, or folded around outlets. These mistakes will deduct from your R-Value as the insulation will not be performing as well as it could.
Cities here in the South Bay, such as Hermosa Beach and Manhattan Beach, we don’t have extreme weather but insulation is still important for keeping your home at a comfortable level by maintaining the temperature and keeping heating and/or air conditioning costs low.
