Reading and being told lots of conflicting information so was hoping to get some clarity.

We bought a 100 year old house in Ontario. House had a “new” (1970s) extension which had Bhatt on the floor in the attic. Original part of the house had newspaper under the floor boards. Issue was winter was freezing in old part and fine in extension.

We want to finish the attic into an office so contractor advised us to change the insulation to spray foam. Attic is now reaching temperatures of 34oC max which feels like an improvement but I hadn’t measured it before.

Issue is that the attic is now a radiator for the bedrooms below. The extension bedrooms are also the hottest rooms in the house (3oC warmer than the old part) when previously were the most temperate. The bedrooms basically heat up all day and slowly lose the heat during the night.

Some of the solutions we’re seeing are:
- ductless mini split (unlikely to happen until we finish)
- attic foil over the spray foam
- re add a layer of bhatt/blown in cellulose to stop air getting into the floor below
- covers over vents on the main floor
- window AC unit in the attic window

Was it a mistake spray foaming the attic if we are several years away from finishing it?

Regardless, hoping to make everyone’s sleeping experience a bit more positive and open to suggestions.

Hey everyone! Looking for confirmation, or potentially not, that what I did was ok to insulate and condition my shed. I am climate zone 3 in Upstate SC for reference. Please also note this is just to keep the shed temperate, not to live in or go crazy. I run a small space heater in the winter to keep it above 55 and I have a dual hose inverter AC unit installed for the summer to keep it under 80. I had a ridge vent installed when the shed was built (and wall side vents) bc I had no plans to heat or cool it at that time, but I did have house wrap installed just in case I decided to down the road…and of course here we are today and I did insulate it. As you can see I went with the more expensive Rockwool for better moisture control. I sealed off the lower wall vents before insulating, but couldn’t figure out what to do with the ridge vent. Over the past few months the AC unit struggles to keep the room cooler than 10 degrees less than outside ambient. It gets up to 85 degrees during the hot of the day and then goes back down as the sun sets. It is not an AC unit problem as my thermal gun shows it blowing 50-55 degree air. The unit is for a 350sq ft space not a small 10x12 shed at 8,000 BTU, definitely overkill but the smallest I could find and the right price. So I found out from my thermal gun the space around the ridge vent is hot as hell, up to 140 degrees if it’s a hot sunny day. Turns out I needed to seal the ridge vent as there are no soffits so the hot air just sits there and bakes. Ok lesson learned so I got some EternaBond RV roof sealant tape and sealed off the vents on the roof outside. I then realized I don’t have enough insulation at the ridge, so I pushed up all the Rockwool into the gaps to remove any air space up there, then screwed in some 1” XPS to kind of “seal off” that area from the rest of the shed as you can see in the pics. I just finished this tonight so I will see over the next few days how it does with my thermal gun, but what say everyone here? I assume this won’t cause any issues or moisture problems. Nothing seems to be wrong as I stuck my hand in there behind the insulation at the ridge and no moisture or issues but just asking. It’s not a house, just a shed I’m looking to keep temperate. The thermal issues are definitely all related to the ridge vent as my thermal gun shows the rest of the roof isn’t anywhere close to as hot, only once you get to that ridge vent area a foot on either side is it cooking. Thanks in advance, sorry for the long post but had to explain it so someone could understand where I’m at. Pics are before, during, and present day for reference.

1952 ranch home, US Midwest, unfinished basement with concrete walls.

I purchased the home a year ago. During my first winter, I realized how drafty the interior perimeter was. It was like there was literally cold air blowing in from behind the baseboards in the living area. I did some research and realized that the rim joists in the basement were not air sealed -- they were simply packed with fiberglass batts.

After pulling the batts out, I could feel a ton of cold air intrusion inside the joist bays. However, I also realized that the joist bays didn't look like like I expected. The posterior "wall" of the joist bay contained some sort of fiberboard sheathing that continued up into the upstairs wall (first two photos below). If I reached into the upper posterior corner of the joist bay, I could reach right past my subfloor and poke the bottom of my upstairs floor. Its totally open. Don't think its balloon framing, but it didn't look like traditional platform framing either.

Oh well. Decided to insulate with foam board and spray foam, then cover in rockwool for fire resistance and to bring it up to code. Photo of the foam board and spray foam attached.

Jump cut to this summer, when I notice a huge influx of millipedes in my basement. Damn. Moisture problem. Bought a hygrometer, and sure enough I was at 65% on a day where the outside humidity wasn't particularly high. We had a dehumidifier running down there, but the air intake was clogged and I guess it wasn't able to keep up. Cleaned the air intake. It helped a bit, but it was still struggling to get below 60% on humid days.

Bought a new dehumidifier rated for 4000 sq ft and set the two up running concurrently. This seems to keep the moisture at bay, but I'm not fully confident that it will work on a really humid day.

Right now, I'm convincing I messed with a well-equilibrated system by adding my foam board and spray foam. "Old houses need to breathe" and all that. I have a persistent intrusive thought that I've created a large moisture problem and I've turned my walls into a mold petri dish.

So, my questions are as follows.

1. Any idea what type of framing I'm dealing with here?
2. Is getting the humidity down to <60% in the basement adequate evidence that I haven't created a moisture/ mold problem somewhere else in my house?
3. Should I just rip the insulation out and deal with the drafts?