Off topic - but any thoughts on this?

[netmouse]

You might have some insight to my insulation problem, given you are all about heating a house. My old Victorian 2-story house has little insulation and has air flow / negative stacking issues. But I am hearing things that do not sound great about insulating a home.

Someone said insulation blown into an attic will shift with air currents in your attic and pile up in places (and be less in other places). I know if you air seal the floor, that protects the heat in the house, but attics still have air currents and this problem sounds logical. And "stuff" will flow through the house by air currents (that are never 100% gone) - meaning fiberglass glass fibers/formaldehyde or cellulose dust/chemicals. And, especially in walls, the blown in stuff will settle over time and become less effective.

Concerns about fiberglass. The newer blow in style sounds like it would be looser and make the floating fibers worse. I've also heard air convection causes air flow through fiberglass, and it is something you can't compact like cellulose to tighten it. You can air seal an attic that may help some. Formaldehyde also is common.

Concerns about cellulose. Chemicals (borate and some have also ammonia-something). I read of an apartment complex suing due to ammonia smell. I have heard the application of the chemicals might not be even and that means places could form mold, not be fire protected, if it gets humid / wet it can get soggy and no longer insulates. Someone also said fiberglass can get mold.

I am more game for something in my attic as that is easier to remove should mold or something happen. Walls would be a costlier problem to remove anything.

Anyone have any thoughts? I may be hearing a lot of competitor propaganda.

 

[Dakotas Dad]

We have blown in cellulose. It's been up there 15 years. It appears to all still be where I put it. (as of last week).

There are some people who are "concerned" about everything..

Considering millions of homes have it, if there was any real problem it would be all over the evening news like shark attacks in Florida.

Lawsuits are no way to judge anything. I can sue YOU right now for the fact that I have a cold. Means nothing.

My guess is the easiest to remove later would be fiberglass bats. Wouldn't want to do it, but it could be done. Of course blown in could be sucked back out I guess..

There are about a dozen "if's" in your statements above.. most of which are pretty far fetched.. Has your attic gotten wet before? If not, why is it an issue with choosing insulation? If a storm tears your roof off/open and your insulation gets wet.. I doubt it will make a difference in the long run..

EDIT: BTW, anyone who tells you insulating your home is bad, is an idiot. There is a cost/return point. And you can build a home "too tight" but I doubt you could easily cause a problem in an existing home.

 

[branchburner]

https://www.hearth.com/econtent/index.php/forums/viewthread/59204/

 

[billb3]

Insulation is for retaining heat.
Barriers are for stopping breezes.

You need both.
Don't ask either to do a job it can't do.

 

[Highbeam]

So what's your question?

Any material used for insulation will have pros and cons. None of the common materials are bad and none are superior in all aspects. You really can't go wrong with cellulose or fiberglass if it is installed properly. You also can't go wrong by implementing all of the air sealing techniques.

Neither FG or cellulose do well if wet. All are easy to remove. I would actually prefer to remove blown in insulation with a big huge vacuum than to handle those batts.

If you have a specific decision like between blown in FG or blown in cellulose then ask that.

 

[moosetrek]

Not sure how much air flow you'd need to move the insulation arond the attic, but it would be a lot! More than I would expect to see unless you have big open windows or holes up there. If it worries you, seal the air leaks first, then add insulation. Pretty sure it won't get through drywall or plaster, or caulk and foam at the cracks. If your furnace system is properly sealed, it won't get passed around the house, all in all I think if you seal your cracks and insulate you'll be fine. You could, I guess, look at foam-in-place but that may be pretty expensive. I'd just insulate, seal, and not wory about it - probably worse stuff floating in the air of most homes than insulation.

 

[fishingpol]

I had air sealing done last fall through an energy program. Air sealing was done in the basement for any penetration to the first floor. I have soffit vents and installed a ridge vent a few years ago for air flow on the underside of the roof. As far as air currents within the house, I would expect the attic space to be reasonably sealed from the lower floors and walls of the house. The only air currents in my house that I can tell is when the stove is going and warm air is rising up the stairs and cold air exchanging downward. I'm sure there is some degree of air movement to the basement from outside in little cracks, but a combustion test was done before and after to make sure the job was not too tight.

One needs to make sure all old knob and tube wiring is replaced before insulating. I've noticed no odor from the cellulose insulation. House is much warmer and holds the heat better.

 

[moosetrek]

At least the old homes had open stud cavities - makes pulling new wiring a LOT easier. But yes, you definitely don't want 90-year old K&T wiring buried in insulation.

 

[benjamin]

Insulation is for retaining heat.
Barriers are for stopping breezes.

You need both.
Don't ask either to do a job it can't do.

It's usually not easy to install an air barrier in an old 2 story house. Dense pack cellulose is a good alternative, foam might be as well but I'm not familiar with it for walls. For the exposed attic floor spray foam, or expanding foam in a can, or caulk should be used before the big mess is made.

All of the concerns are legitimate. Cellulose will make a house dusty. Maybe only until it's vacuumed out, or maybe it will always be dustier. Most cellulose contains both boron and ammonium sulphate which will release ammonia if wet. Insulation getting wet is definitely something you want to avoid. Also the book says insulation should not be applied around live knob and tube wiring.

Insulation will only blow around if you have an eave that is exceptionally exposed and open, this happens sometimes but it's usually just one small corner of a ceiling that suddenly gets condensation, or feels cold. If that's a problem then feel free to live with the whole ceiling cold.

 

[netmouse]

Thanks everyone. Info from anyone who can comment helps me a great deal. I did have the tube & knob electric wiring rewired last Fall (about 1/2 the house still had that). I knew it had to be done, besides insulation via the state energy program, but also when one insurance company would not insure my house because of it (my current insurer just had a fee, I think about $40, for an "old house"). And I hear it can be a sticking point today in ability to actually sell a house. It may become like lead and other bad bad bad things.

 

[flyingcow]

My 1st thought. Blown in insulation. have it in my ceiling, no problems. getting ready to do more up there next year. Been 15yrs, a little settles, but not much. just want to increase R value. BUT, if you have enough air currents to blow it around and settle elsewhere.....you got problems i don't want. No matter what type of product you use, if it's that damn windy in your attic, find the holes. And if it's that windy, F/G or cellulose will loose R-value from the rain that blows in also. I'm sure you don't have that much of a wind/current problem, but it's worth looking into. Any water issues need to be addressed before install of insulation.

If you got the time, rip out the interior walls and spray foam or install foam in between the studs. Very drastic and time consuming, but it will work the best. i am considering doing this in my house. I did the typical R-19 in the wall(F/G) and wished i would have foamed in between wall studs. F/G looses R-value over time.

Good Luck