Answer "How to Insulate an Attic"

Actually insulating anywhere is one of the easiest parts about building/remodeling any structure.
There are a couple of ways to insulate an attic and several different insulating materials to use. In purchasing your insulating material the thing you want to look at is the "R" factor. This is the rating scale used to determine how much heat/cool loss will occur through this material.

R-value

A materials resistance to heat flow is called its Resistance-value or better known as R-value. Having high R-value will ensure that your rooms are mores comfortable. insulation installed in the cavities of your home slows the flow of heat through walls, floors and ceilings. Therefore reducing you energy consumption.

The higher the R-value, the more effective the insulation. For example, heat flows through an R-8 wall twice as fast as through an R-16 wall. Different types of insulation have different R-values per inch, and have varying construction and insulation applications.
Fiberglass insulation usually has an R-value of approximately 3 per inch. Cellulose insulation is made from treated, recycled paper and is generally blown into finished walls, attic floors and other hard-to-reach enclosed cavities. Dense packed cellulose has an R-value of 3.8 per inch.
In my opinion the blown cellulose is not only the best insulator, but also the easiest to install by simply renting a insulation blowing machine, wearing a mask to keep from breathing the fibers and blow this cellulose fiber in the attic and other areas. A 10 inch layer is, in my opinion, a minimum for the attic which will give about a R30 rating. I personally prefer a 14 inch layer. About every 15 or 20 years you will need to check the depth in several places on a 10 inch layer because the dynamic shifting of the movement of the structure will cause packing and you may need to blow in another couple of inches to keep the R-value.
The other method, which I don't like is the fiberglass batts. These are a pain in the you know where to install. You have to hand fit and cut to cover every square inch of surface, taking particular care to cover under any wiring connector boxes, in the attic and staple the paper covering to the lathing or cross beams in the attic.
For every square inch of surface not covered you will lose a small percent of R-value. Each of these small areas add up and if there is enough it will add up to the equivalent of having a window open in the coldest or hottest day of the year. Remember heat rises and since the attic is the highest enclosed are in your house it retains most of the heat. If it is well insulated this heat stays in the living area where it belongs.


No, I'm not a professional installer. I've just insulated my own home when we were building it and learned a lot from some very informative companies. After insulating the house I lived in for 25 years, only once did I have any frozen water lines (an entrance hole for the waterline was missed) and during the "Ice Storm of the Century" during 2000-01 where it spanned over the two centuries for a 3 week period, the temperature inside that house with no heat from any source for 10 days never dropped below 50°, which tells me I did a pretty good job.


In most cases it is cheaper to have it done professionally. By the time you add up travel, material, and your labor you can spend hundreds more doing it yourself, depending on the size of the project~