Adding wall insulation to an existing home.

[David S.]

Does anyone know anything about adding insulation to exterior and/or interior walls of a mid 90's stick built home?

We added a bunch of blow-in insulation in the attic when we first moved in. Now we're convinced we need to do some or all of the walls as we have several rooms in our house that aren't keeping up with the HVAC, particularly on the second floor. Very cold in the winter and hot in the summer.

Based on a brief search, it seems injected foam insulation is the way to go.

Anyone have any experience with this or any other method?

[rd62]

Seems like a pretty new home to not have sufficient insulation in the walls, ceiling, and floor. I've seen the blown insulation in attics settle and loose some R value over the years and subsequently had to blow more but I'd have thought the walls would be good to go. HVAC system is good to go?

[miller_man]

Speaking a touch out of my lane, but have 20~ yrs exp. in/around houses/construction. Upstairs are almost ALWAYS hotter/colder. 2 things I've always heard in all my years - people always end up wanting single level homes for 2 reasons - no stairs and better climate control.

That said, I'm not aware of anyway of adding/changing insulation without opening up all the walls. Spray foam expands and no way to pump into a wall and not have problems. Think you can have a energy savings type evaluation done. Other than that, think a good hvac guy looking at your system and seeing what can be done is best bet.

[Snapshot]

Speaking a touch out of my lane, but have 20~ yrs exp. in/around houses/construction. Upstairs are almost ALWAYS hotter/colder. 2 things I've always heard in all my years - people always end up wanting single level homes for 2 reasons - no stairs and better climate control.

That said, I'm not aware of anyway of adding/changing insulation without opening up all the walls. Spray foam expands and no way to pump into a wall and not have problems. Think you can have a energy savings type evaluation done. Other than that, think a good hvac guy looking at your system and seeing what can be done is best bet.

My place was built in the late 1950s, oil was cheap and insulation was pretty sparse. My neighbor's house is a clone, the previous owners did a lot of updates including adding rigid foam insulation on the outside, applying it on top of the existing brick veneer, then finishing with some sort of stucco. This avoided ripping up interior walls and whatever else may have been needed for adding insulation that way. It looks great and along with replacement windows and something for the attic they said it significantly improves the thermal performance of the building.

[Darth_Uno]

If you’re due for new siding, we recommend adding foam panels on the exterior. Even something like this can make a difference. https://www.homedepot.com/p/Owens-Co...21UM/100320301 It’s the least intrusive measure, but also has a high labor cost if you’re not getting new siding at the same time. We could just take down and reinstall existing siding, but that’s a lot of labor cost with not much to show for it.

We also always recommend a separate HVAC system for the 2nd story. Could be an entire furnace and condenser/heat pump, could just be supplemental in-wall or PTAC units. That ultimately allows for more temperature control than just adding insulation to areas that the primary HVAC still struggles to maintain.

[David S.]

HVAC is functioning fine, though the outlets may be poorly balanced. Attic insulation was updated three or four years ago at 20" deep, IIRC.

Knowing nothing about anything, this Injection Foam Insulation method appeals to us.

[Irelander]

I haven't done it, but some of my friends have rented a thermal imaging camera to scan the outside of their home on a cold day to find out where the heat is escaping. This gave them the precise locations to investigate and fix the issue. Might be worth it to find out where the issues are instead of spending more money to re-insulate the whole upstairs even where you don't need to. Just a thought.

[bofe954]

I haven't done it, but some of my friends have rented a thermal imaging camera to scan the outside of their home on a cold day to find out where the heat is escaping. This gave them the precise locations to investigate and fix the issue. Might be worth it to find out where the issues are instead of spending more money to re-insulate the whole upstairs even where you don't need to. Just a thought.

The utility company around here does energy audits. I think it's less than $100. They have the thermal cams and they can blow air in with a fan and look for leaks. Might be worth it before you spend thousands.

My old house you could adjust the airflow in your ducts to different places. Might be another option, just blow more heat/cold upstairs. If your thermostat was upstairs you might be complaining that it was too hot downstairs...

[psalms144.1]

HVAC is functioning fine, though the outlets may be poorly balanced. Attic insulation was updated three or four years ago at 20" deep, IIRC.

Knowing nothing about anything, this Injection Foam Insulation method appeals to us.

The problem with expanding foam in the walls is it doesn't expand evenly, and can cause issues with drywall bulging/cracking. When we had this problem in our NY house, the answer (not cheap) was strip the cedar shake shingles, add rigid foam exterior insulation, and vinyl side over that. None of the contractors we talked to would even discuss foaming between the sheetrock and exterior sheeting.

[miller_man]

The problem with expanding foam in the walls is it doesn't expand evenly, and can cause issues with drywall bulging/cracking. When we had this problem in our NY house, the answer (not cheap) was strip the cedar shake shingles, add rigid foam exterior insulation, and vinyl side over that. None of the contractors we talked to would even discuss foaming between the sheetrock and exterior sheeting.

I watched that video and my first thoughts are - the wall "cavity" they are pumping the insulation into is NOT just an empty space - the previous insulation, bracing, electrical wires and plumbing could easily block the foam from getting to lots of the areas. I would imagine the must have a MUCH less expanding foam mixture the use or else it could definitely cause issues with interior drywall. I would LOVE to see that process completed on a couple of walls in a house and then take one side of the wall off and see how well it performed in filling the space.

Maybe that option works great, I'm not sure - but I would absolutely want to see some proof before I dropped any money into it.

Welp!! I should just research a tad more before thinking about posting stuff mentioned above. Went back and watched a few more videos from that company. First thing I noticed - they are a pretty solid looking company and they are obviously involved in charities - I had a tiny bit of "slick used car salesman" vibe from guy in video, but I think I am wrong on that one (maybe it's the earrings and whole university/chair thing going on). Second - spray foam is completely different than foam injection, they go into this in videos. Thirdly - they show A LOT of the process and even pricing ballparks upfront, on a youtube video. Also, they have a video clip displaying exactly what I wanted to see - the foam injection being shot into an existing (mock) wall and going around existing insulation.

That actually looks pretty interesting and a quite easily a very effective solution to insulating existing structures with foam insulation.