Loose-Fill Insulation

brownstones11

Does anyone know of a good-loose or blow-in insulation for the interior of an outside wall?

EdTheHeaterMan

yes

kcopp

Cellulose would work. It would be probably the most cost effective too.

psb75

Dense-pack cellulose.

The Steam Whisperer

I've used dense pack fiberglass...I have concerns about the long term flammability of cellulose and the issues of smoldering.... See here for example.
https://www.firefighternation.com/2011/11/28/fire-cellulose-insulation/#gref

I've also been told directly by 3 generation firefighter families about this very problem.

Jamie Hall

Loose fill blown in is also available in fiberglass -- which is at least itself non-combustible. I share @The Steam Whisperer 's concern about flammability, and add the remark that if one has older electrical wiring in the walls, one must be sure that it is protected with arc fault interrupting breakers of the correct rating (probably 15 amps) for the wire. This applies even with fiberglass, as you really don't want to risk the wire overheating -- and it wasn't intended to be surrounded by insulation.

There are times when a drive for energy efficiency needs to be sanely balanced with a concern about safety...

PC7060

I’ve used BIB (blown in blanket) on a historic job where spray foam wasn’t allowed. Essentially pumping in the same fiberglass that’s used in attics to get a dense pack with nice R value and good draft stopping capability. 

Not heavy so it doesn’t pump as well into closed walls.

This same house had blown in rock wool insulation in some of the original sections. Think the works was from the 1980 and the installer did a nice job from the few sections I had to clean out as part of the additions I did. 

PC7060

We did the attic floor with same system and then put subfloor down over it. Put a second layer of 2x6 framing perpendicular to the original trusses to get 11” of dense pack fiberglass (approx. R45). 

 

Sealed the 9” plenum duct and 2” lines for the Spacepak High Velocity system into chases and under floor so only the air handler and short section of plenum is in unconditioned space. 

psb75

Cellulose treated with borates has a Class One Fire Rating. That is the principal reason for the borates. However, they also inhibit (if not prevent outright) RODENTS and insects. I have yet to see any major infestation of rodents in cellulose. While the bulk of my career has been spent observing, handling and removing rodent infested FIBERGLASS. Rodents...love...fiberglass. Why? They can "structure" it, i.e. tunnel and nest in it. They can't in cellulose, and the borates irritate them--a lot.
Cellulose insulation is ground-up recycled newsprint. Borates are a derivative of borax and the element boron. Remember "20 Mule Team" laundry soap?

The Steam Whisperer

If you get a chance read up on the meaning of Class One Fire rating....it does not mean that the material can't smolder. Read the link too.

Jamie Hall

The Steam Whisperer said:

If you get a chance read up on the meaning of Class One Fire rating....it does not mean that the material can't smolder. Read the link too.

And please... go back and think about my comment on the electrical wiring.

To which I will add. No buried junction boxes. No buried splices. No knob and tube or independent rubber/fabric insulated wires (they're OK inside metal armor or conduit, provided you have arc fault breakers). And my personal quirk: derate the wiring one rank if it's going to be surrounded by insulation. That is, 14 gauge is 10 amps, 12 gauge is 15 amps, 10 gauge is 20 amps. That's not explicitly in Code -- or it wasn't; it might be now) but is just prudent.

The Steam Whisperer

There are numerous articles about the issue of electric wiring overheating..... this applies to any added insulation that encapsulates old wiring. I am in Chicago and everything here was run in conduit in my 1903 home and I have pulled all new higher temp rated wire in the old conduit and the several hundred feet of new conduit. I have dense pack fiberglass walls and a mix of old rockwool, r-25 fiberglass batts and dense packed fiberglass in my ceilings.

Jamie Hall

You're fine with the high temp wire.

The Steam Whisperer

I had all cloth covered wired, except in many junction boxes where the cloth had largely deteriorated and fell off... it was pretty scary.

Solid_Fuel_Man

Old wireing is scary enough w/o insulation. 

I wouldnt want or have any old wireing in my home. 

JUGHNE

IIRC, K & T wiring could be fused at 20 amp for 14 AWG because of the theory of being in free air. Any insulation at all is forbidden to cover it.

Actually most K & T wiring end up with 30 amp fuses or the "magic penny assistance".
And yes fires, especially if insulated with anything.
Being fewer surviving K&T systems, they either burned down or were rewired.

Even early Romex cable brought into ceiling light J-boxes have cooked conductor insulation. Because of oversized bulbs installed and then attic insulation covering the box.

The Steam Whisperer

Yep, I saw every kind of wiring I think there was ( short of in conduit, which I installed) in my old house...K &T, Cloth covered wire romex, rubber covered wire with cloth out shell romex and new romex. Romex..... not even as good as extension cord wire....