We are all looking for ways to make our homes more comfortable and lower our utility bills. I get lots of calls and emails asking me about various products that are sold at the local big box improvement stores and by local home improvement contractors. Because of the need created by home owners and the ingenuity and marketing budget of manufacturers, there is a LOT of misinformation out there.
One of the products that’s making a big push right now is radiant barriers. A radiant barrier is a reflective material that is used to reflect the radiant heat created by the sun and reduce its ability to be transferred into your home. They are most commonly installed in the attic. Common brand names are eShield, Relectix, Enerflex, EcoFoil, etc. Here is an article written by the Dept of Energy.
Here is what you need to know:
- Radiant barriers are NOT a substitute for proper air sealing and insulation, they are a compliment.
- In our climate, radiant barriers do very little to reduce your heating costs.
- In most cases, radiant barriers are only going to reduce your cooling costs by 5% - 10%, NOT 40% as many will tell you.
- Unless you have HVAC equipment in your attic, installing a radiant barrier is a waste of money. (You can just add a few more inches of insulation at time of install for less.)
- Radiant barriers must be properly installed over 80% of the surface area to be effective.
- In our climate, radiant barriers should be installed below the roof deck NOT on top of the insulation (dust accumulation greatly reduces its effectiveness).
Don’t be fooled by a good salesman. Science trumps sales pitches every time. There are instances where radiant barriers are a good application, but you need someone other than the salesman to figure that out. The best way to find out what your home needs is to have an energy audit.
Until next time….“Don’t throw money at your problems, throw knowledge, it’s a lot cheaper.”