I have a 100+ year, balloon framed house with no insulation in the walls. The exterior is stucco; the interior is plaster and lathe. In a couple of tests there were no fire stops from the top of the second floor wall to the basement.
I have no desire to drill through the stucco and will have to blow the insulation through the interior walls. Is it possible to fill the whole cavity from a second floor hole? Is it imperative to remove all of the knob and tube wiring? Most has been removed, but still have some running around to baseboard outlets.
Final question. As I am planning on doing this myself, I will be getting the blower from my insulation supplier. I noticed the delivery tube is probably 3-4 inches in diameter. Doing some internet research on this subject, I found some articles and pictures showing a 2 inch delivery tube. My thoughts are that a 2 inch tube would be easier to insert into the cavity and drop it down and that a hole for a 2 inch tube would be much nicer than one for a 3 or 4 inch tube. Can you reduce a larger tube down to 2 inches? Or is this specific to the equipment?
Replies
Someone posted an answer to a similar question earlier, but their reply about knob & tube was that it should all be removed. The rest of your questions, I'm not sure of answers, but someone else will undoubtedly reply before too long. You might try to use search to find similar threads that were answered in the past. Key word "cellulose" would probably do it. "Balloon framing" might also be a good search word. (I tell you this because I didn't know how to do searches until recently and thought maybe you might not....)
It's been a long time since I had anything to do with the installation of blown cellulose, but my recollection is that it has to be packed in pretty tight. I don't think just letting it free fall from the top floor is sufficient.
In a pinch we have done as you are suggesting and frankly I consider it a failure. Cellulose is meant to be packed in in order to really work well and to give it enough material for it not to settle a great deal.
You can drill the inside with a pair of 1" holes upstairs and downstairs and do a traditional installation. It is dusty so covering anything that matters is important if you are going to install it in the interior.
A number of people here consider knob and tube a problem with cellulose. I have blown insulation in probably 50 house over the last 20 years and never worried about it. All of them are still standing and I have never heard a complaint or issue. DanT
Thanks everyone for your replies.
DanT - I now understand the necessity to blow cellulose to the proper density, but is it possible to drop a hose all the way down from the second floor in the wall cavity to the first floor and effectively fill. As you can tell, I'm trying to avoid drilling on the first floor not to mention the mess created by the installation of the insulation.
Always looking for a better way, but doing it correctly is most important.