How To Install Insulation | Do It Yourself

Still Have Insulation Questions?

You Can Contact Itchy For The Answers!

Recent Articles

Should I Add Additional
 Insulation To My Walls?

Should I Insulate
 The Wall Plates?

Blowing Insulation Over 
Recessed Lights

Ventilated Attic 
Access Covers

Insulating An Attic 
With No Access Hole

Adding Additional Attic 
Insulation Over Fiberglass Batts

Skylight Covers To
 Reduce Air Infiltration

Do I need a vapor barrier?

Insulating Over Knob and
Tube Wiring

Vapor Barriers On
Basement Concrete Walls

Insulating The Ridge Of
Cathedral Ceilings

Adding Insulation 
Over Vermiculite

Recent Posts

Hi Itchy,

I have determined that my attic is under-insulated. Our town allows for a a free energy inspection of your home, they pay the inspector, to give advice as to how to make your home more efficient.

The inspector told me I need more insulation in my attic. Not surprised, this house has always been cold. But, he did say I have to be very careful as the existing insulation, which is clearly not enough, is some stuff called vermaculite. I guess this stuff has asbestos in it. I have a respirator, Osha approved for working around asbestos, and except for anticipating having to shove some insulation in the corners and around attic baffles so I don't block soffit vents, and probably on my stomach on plywood, it should be a matter of rolling the insulation out. Before I get around this stuff, I wanted to ask someone that would know, their opinion about working around this vermaculite stuff.

Thanks in advance for your opinion.

Rick

I have ran into vermiculite insulation many times during my insulating career. It is a flaky mineral that looks similar to mica.... read more

Hello,

We are in the process of insulating a cathedral ceiling in our remodeled house. We had to pony up to all the existing rafters with 2 x 8's as they were too small (house was built in the 60's with rough sawn fir... good tough stuff, but 2 x 4's don't allow much airflow, with proper R value insulation!) We put in the "rafter buddies" in every space from the very peak to the soffits. (We just had the roof redone so there are many vents, and we just redid the soffits with the alum kind instead of the vents in solid material that was there before!)

My question: how do you insulate at the very peak? Insulation is square, the peak is not... do you just stuff more in that triangular gap? Like I said, we have put the foam rafter vents in the entire length from the big peak beam to soffit. I just don't know how much to stuff in that space. Fill it up with scrap? If so, does it matter what direction the scrap goes in? I would think the gap needs to be filled, but want to make sure its done properly before my other half puts the vapor barrier up!!

Thanks!!

Jo-Ann

Normally with vaulted or cathedral ceilings you would start insulating from the top and work your way down. The batt of insulation is butted against the ridge beam (peak). Because of the angle you will have a small triangular area that could use more insulation where the batt meets the beam... read more

I am insulating my garage and need to know if I need to apply a vapor barrier between the concrete walls and the wool batting. The walls are poured concrete and have been framed out. I received a supply of wool batting but although the manufacturer says it resists the moisture, I live on Orcas Island in Washington and moisture is out life out here. I will also be putting it in the ceiling. So I wanted to be sure about the layering before getting started. I am doing it myself to cut costs so I would appreciate any free advice you pass along to me. Thank you so much.

K.M.
Orcas Island, WA

Vapor barriers - to add on or not. Everyone has an opinion on this one and that includes me. My experience tells me that unless you live in a desert climate you need a vapor barrier. Many builders don't add vapor barriers to garage walls as they are not considered a living space. The purpose of the vapor barrier on concrete garage walls is to prevent warm air from condensing on the cooler garage concrete walls. If that happens moisture can run down the garage concrete walls and you may experience dry rot, mildew or mold...read more

Hey Itchy

My old home has knob and tube wiring in the attic floor. There is no insulation over it and I'm am losing a lot of heat. What's the best way to insulate over knob and tube wiring?

Marcus B.
Northern Michigan

Adding insulation over knob and tube wiring can be dangerous and you have several issues to consider. While I've insulated over knob and tube wiring a in the past (only because the owner insisted) I wouldn't recommend it. They actually had plywood boxes built to completely cover the old but but live wiring and we were able to insulate over it. You would never want to directly cover it with insulation though and I'll tell you why... read more