I have an old house, circa 1900.As you can imagine, the insulation is pretty much non-existent, except for the attic, and even that is piss poor.The plan is to get a blown-in insulation machine and get about 7 bags of blown-in insulation, then cut holes in the drywall on exterior-facing walls, blow the insulation into the stud cavities, and then patch the holes. I can't insulate all the walls, because there's still some knob-and tube wiring present in places. (Fortunately, I have a basement, and it's all been run through there, so locating it is no problem.) However, I can insulate about 1/3rd of the exterior-facing wall space.Am I going to get any real benefit from a partial insulation job, or would I be better off just saving my money and putting it toward insulating the attic?(I'm going to redo the attic insulation eventually, but that's going to be more time, money, and effort than I can spare right now.)
>>2880896It can't hurt but I've heard it's better to address the attic first (which makes sense since heat rises). Comfort-wise fix any drafty windows and doors too, because they might not be the biggest source of air, but you can feel them and it just sucks.
I have a 1940s house that is insulated with Kimsul crepe paper insulation. I have debated gutting it room by room to re insulate, since they drywall is looking rough anyway, but it doesn't seem like a good return on investment. Attic is decent with blown in rock wool>>2880896I dunno if that loosefill is the best stuff to use in walls, especially if there is any possibility of moisture intrusion. Might be worth hiring a pro to do the walls with expanding foam. I think they can do it with really tiny holes.
>>2880980>expanding foamI've read some horror stories about the foam, though apparently it's good under perfect conditions, but you can't trust the installers to do due diligence they just want to fill the walls up and gtfo. >any water intrusion becomes a 100x bigger problem>off gases for a long time and makes some people sick>pain in the ass to remove (say when fixing that water intrusion problem)
>>2880896why can't you blow insulation around the knob and tube?
>>2880896very little to no effect. you need to add a layer of wind breaker on the outside to get the true benefits of it, if not the cold draft just blow straight through it.i did that on my 1893 apartment in a wooden house. ripped out everything and layed out windbreaker tyvek and as much glasswool insulation as i could in every cavity i could. even spaced out two walls and lowered the ceiling, not just for insulation but for sound damping.the effects are out of this world, i needed 5kw to keep temperatures during winter before and i could hear my neighbours fart, now im at around 1-2kw and i hear nothing.
>>2880896I would save up, do a layer of exterior foam insulation (reference building code for the minimum you need to ensure no condensation - zone 5 is r7 minimum for reference) tape the insulation with flashing tape so you have an air barrier and then redo the siding and trim. You'll then have an even half ass insulation job instead of random hot/cold spots
>>2880896>there's still some knob-and tube wiring present in placesholy shit fix this firstI don't even think you can legally sell your house without getting rid of that shit
>>2881088it will cause the wire to overheat and start a fire
>>2881091>>2881094Thanks, fellas, I'll try a combo of these.
Make sure your walls don't have any water intrusion. Any at all. Hollow walls dry out pretty well but you put insulation in there and you'll give yourself a much more expensive problem.
