DIY Blown-In Attic Insulation

We field questions every day from homeowners about how to improve the efficiency of their homes and lower their energy bills with insulation. Obviously, there are a ton of places to insulate but one of the most important and also accessible is the attic. A typical home will lose a lot of heat through the attic in winter while gaining quite a bit in summer. So with that in mind, let’s dig into why blown-in attic insulation is a great idea.

Why insulate your attic in the first place? 

Insulating your attic is a no-brainer. It is one of the easiest ways to improve the performance of your home and lower your energy bills. Due to the “stack effect,” a house can lose a lot of heat (or cold) through the attic. A typical example: in the winter, cold air enters the bottom sections of a home and warm air rises through air leaks into the attic. Not only does this air transfer cause heat loss but it also creates moisture issues with vapor drive. A properly sealed, insulated and vented attic can prevent all this. 

To determine if your already somewhat insulated attic needs more, you can do a few checks and follow some rules of thumb. Looking across your attic, if the insulation is level with or below the attic floor joists, you probably need to add more insulation. Either read the R-value printed on the batts of your existing insulation or use a measuring tape/ruler to measure the depth of the insulation (inches). You will want to record your measurement so you can determine how much more insulation you need to achieve the recommended levels. EnergyStar provides the below guidelines on coverage.

Air sealing is critical 

An attic has lots of places where air can leak. As discussed, getting these areas sealed up is step one. There are tons of online resources for learning about air sealing. Regardless of method make sure you address any penetrations – plumbing and chimney chases, partitions of interior walls, etc. Expert tip: if you have existing insulation in your attic, look for areas where dirt has accumulated on the insulation. That’s often where air sealing is needed! Note: attics typically require ventilation; do not seal the vents.

A quick note on recessed lighting

One important consideration when insulating an attic is how to deal with recessed can lighting. Nowadays there are 2 types of recessed can lights: IC rated and non-IC rated. (IC = Insulation Contact. IC-rated fixtures are designed to be installed in areas where they will be in direct contact with insulation. This is important as non-IC-rated recessed lighting in contact with insulation creates a fire hazard. Pay mind to any recessed can lights and their rating. Obviously, life (and insulation) will be easier with IC-rated lights!

The best blown-in attic insulation

We highly, highly recommend using blown-in insulation for your attic application. Unlike batts, blown-in was developed to be high-performance insulation installed with a blowing machine (for very small projects, hand stuffing will work). The material is forcefully blown into a cavity enabling it to wrap around and get behind common obstructions. This creates exceptional coverage and performance, i.e. R-value,  which is critical for properly insulating your attic. Our blown-in attic insulation has an R-Value per inch of 4.3 vs our batts which are 3.6. Also, the sound absorption is a bit better (95%).

Our blown-in insulation when paired with our recommended blower can be blown into an attic very efficiently. See our coverage chart to determine the proper amount of insulation to use.  A very important note here is to understand the density required to achieve the desired R-value.  As the wool opens it is easy to under-insulate.  To avoid any issue just reach out to us and we will be happy to help.