Which is better attic insulation - blown in or rolls?

Question

I have a brick ranch house, built about 60 years ago. The crawl space above the ceiling and under the roof is not that high to be working in...it can be done though.

The current insulation, which is of a loose type, (I have no idea on what type it is) has shrunk to about a 1/2 inch in thickness.

Which is better, economically? Which is better to put in, considering the small working space? I have approx. 1600 sq. ft. to insulate.

Answer 1

blown works - to a point. but how can you ensure even coverage in all the corners,etc. Unfortunately, getting in there and sweating and itching from 8" fibreglass batts is still the best and most consistent way. Lay one set fitted between the joists, then another laid at right angles crosswise over that. 16 inches of insulation, and you know that is what you have, not ten inches of cellulose here, but maybe only 2" in a corner or just along a joist where the air currents didn't carry the fluffy crap properly. A pain in the butt job, but worth doing right. Just don't lift your head too high or you'll get puncture wounds from the roofing nails sticking down into the attic space... and fibreglass is 2x the expense...

Answer 2

This Site Might Help You.

RE:
Which is better attic insulation - blown in or rolls?
I have a brick ranch house, built about 60 years ago. The crawl space above the ceiling and under the roof is not that high to be working in...it can be done though.

The current insulation, which is of a loose type, (I have no idea on what type it is) has shrunk to about a 1/2 inch in...

Answer 3

Oakridge National Laboratory created a chart listing the approximate R-value per inch for the various types of insulation. Aging was factored into the lab’s figures.

Once you determine the existing R-value, you can tell what you need to get to bring the R-value up to your region.

You could get the extra R-value in just one layer of R-30 batts. This, however, would leave the joists exposed and structural lumber has proven to be a key source of heat loss. You get a better insulation job by using two layers of R-15 batts. The first layer goes directly on top of the existing insulation, inside the joists. The second layer is placed horizontally across the joists. The second layer encloses the joists, making the insulation more effective.

A more efficient method would be to use blown-in Fiberglass or cellulose. Both would fill all the gaps and enclose the joists completely. Blown-in cellulose gives slightly more bang for the buck because it seals out drafts as well as insulates.

Whenever you use blown or loose-fill insulation, it is important to install attic ventilation channels (rafter baffles) to keep the soffit vents from being accidentally blocked. It’s also a good idea to increase soffit and roof or ridge venting whenever you add insulation.

Answer 4

Rolled Insulation

Answer 5

For the best answers, search on this site https://shorturl.im/av6A8

Insulation also come as "Batts" which are 4 foot by 16 or 24" wide . of various R factor ratings(meaning each batt is a certain thickness depending on how high an R value you buy. As most people or builders do not have an insulation blower in their back yard buying batts is the way to go as you can insulate the house yourself using batts. Measure the depth of the cavity and the width of the cavity and you know how much room there is. Attic is either 2x6 or 2x8 or 2x10 depending on the age of the structure. When you get a bundle of batt insulation it is many batts compressed by machine and wrapped in plastic. It would be best if you could carry the whole bundle up to the attic before you cut the plastic. If you cannot get it up there because the attic hole is too small, then open it in an empty carport or garage. Use a razor knife and gut it like a fish.(you only got to cut through the plastic). Then you will have to transport individual batts up the attic. Each batt is meant to fill a cavity by itself as the air pockets within the glass fibers is what is the insulator, not the glass fiber itself. It is meant to be fluffy.. More insulation on top will only be a benefit to your heating and cooling in the summer.

Answer 6

Insulation Rolls

Answer 7

I disagree with those who say Blown is the best in my experience the only ones who say that are contractors using it. We've had awful experiences with blown insulation's.
Roll type is far more work - no doubt and some Ara's can't be gotten into as well. But the blown stuff tends to drift and pile in one place. It also tends to settle after time.
We retro-blew insulation into the attic of a 1950's ranch house and it was a total waste of money. We are now planning to DIY it with roll type.

Answer 8

Blown in is by far the least expensive and perfectly fine to use when properly installed. It comes in many types of material with different "R" values per inch of depth ("R" is a standard measurement of insulating properties). So you should get quotes based on the same total installed "R" value.
Depending on your location this is a big factor in cost. Homes in the Northeast require an R-30 or more while down south it may be as little as R-19 (33% less depth).
The previous answers regarding baffles are correct. The insulation must have open space above it for air to circulate and evaporate any moisture that may work it's way thru from inside the house. If the insulation is packed tight to the underside of the roof it will lead to moisture condensation on the wood then to mold and rot.
Just as important is venting along the top of the roof to provide a convection current from the low eave vents to high vents.
- Hope this helps, good luck with your project.

Answer 9

What's better depends on your situation.  If you don't crawl in there anyway and install a vapor barrier, are you going to have rotting ceilings falling down on your head in five years?  If you need to be up there anyway, batts may be better than blown-in for half a joist height or so because you know you won't have any gaps.

Second the comment about soffit baffles.  You'll need air circulation to keep the insulation dry.

Answer 10

The blown in kind is more economical. It can get into all the cracks and crevices. I had a house down in florida and I had a fire some years ago. When we restored the place, we did the blown insulation. What a savings on our electric bill !!