Need more and better insulation for upstairs
 

We need to insulate our new, old home better. Thankfully, the home was mostly insulated some time in the last 30 years by previous owners. We've got f/g bat insulation in the exterior walls. The upstairs is insulated pretty well (considering the house was originally built in the 1920s).

The floor joists for the 2nd floor are 2x6. The upstairs walls are 2x4. Most of the upstairs walls have a pretty decent covering of 3.5" R11 in between the studs. Most of the floor joists in the attic spaces in the 4 corners have 6" R19 (there's some pink, and some older cream colored. either the cream colored is now compressed or maybe it was originally 3.5"). In the very top of the roof area I assume it's probably more of the 6" R19. I can photograph it with my phone, but there's no access without cutting a hole in some drywall somewhere.

I want MORE, and I don't want to use the sprayed in crap if I don't have to. That might actually be a decent option for over the 2 bedrooms and the open space room since there's currently no human access to those spaces.

While it will be fairly easy to buy some fat rolls to lay out in the corners, I'm not sure how much good those will do if the walls are just a layer of drywall and 3.5" of R11. So I want to beef up the walls. WHat are my options that are relatively easy to DIY?

side view
http://forums.pelicanparts.com/uploa...1624928473.jpg

rough top view
http://forums.pelicanparts.com/uploa...1624928473.jpg

And a couple shots of what I'm working with.
http://forums.pelicanparts.com/uploa...1624928473.JPG
http://forums.pelicanparts.com/uploa...1624928473.JPG

above the 3 "rooms"
http://forums.pelicanparts.com/uploa...1624928473.JPG

I've wondered about some of the pink foam sheets, for the vertical walls on the outside of the studs, but I'm not sure if that will be adequate. Is there a way to attach more bat to those walls?

Any other recommendations? Would it make sense to pull out the old crap or just lay new stuff on top of it?

Spray foam.

An attic fan will help but rigid foam insulation is one of my fav. Simple to install. We cut with a table saw. 3" is plenty for us out here. Between joist, remove old (they aren't good anymore) and install new R 30-60. In the TX heat, your code may require more.

Great stuff. And you can get a special saw blade that is dust free specially for cutting the foam. Still wear a dust mask though.

We've got 2 whirlybirds and no soffit vents. I need to add soffit vents. My soffit is 3/4" shiplap on the second floor and 3/4" tongue and groove on the first floor. I hate to cut/drill into that stuff, but I need something to let air in to replace the air that's leaving out the top.

That's another thing, I haven't figured out exactly how I want to create soffit vents.

OK, so you think get rid of the existing and then use rigid foam, presumably for the vertical walls. What about the attic floor? Just deep rolls?

Yep, roll out new insulation. Check your building code. What you have there isn't enough. Ours are thinker then that. Stuff some of the rigid foam between the rafters may help. I raised the ceiling height and increased the pitch to create an open ceiling feel to this old house. Architect and I agree to use rigid foam, 3" in between rafters.

Cool, thx.

Is there power up there? Looks to me you have a vertical wall there? Cut a hold and install a gable power vent on one end and have a open vent on the other for cross flow. You can go fancy but I like the simple ones on a themoswitch. https://www.acinfinity.com/hvac-home-ventilation/shutter-exhaust-fans/airlift-t14-shutter-exhaust-ventilation-fan-14-temperature-and-humidity-controller/?gclid=Cj0KCQjw5uWGBhCTARIsAL70sLKpI7hCICsAYusRgE4 DFmgrqHR-Q0VBFEsf6q3EnDq2ulFb-Arq-ZoaAtWNEALw_wcB

If it were mine I would remove all existing insulation and start over . While everything is open fix your lack of ventilation . On your vertical 2x4 walls I would install fiberglass or rock wool and over that rigid foam with radiant barrier . That is the foam with the silver foil . If you can do the same to the ceiling do that . Radiant barrier works quite well in high heat areas.

The 2x6 floor rafters , while open fill/seal any openings like vent pipes/light fixtures etc you want to stop all leak paths . Then you can install new fiberglass insulation this can be rolls or blown in . Any box store will rent you a blower for the fiberglass and sell you the bags of insulation . While messy it is a DIY project . I don't like the way it settles but I think it's the best bang for the buck .

Your walls are "okay". I'd focus on the ceiling.
If you really want to beef up the walls spray foam is the way to go. The ceiling you just add more batts.

Unfortunately, I don't think there's anywhere to put a gable. Normally, we could put one above the windows in the dormers, right?
Unfortunately, the only vertical walls on the second floor would go directly into one of the rooms.
http://forums.pelicanparts.com/uploa...1624968417.jpg

I've been wondering about some sort of radiant barrier. And I feel like I need something more for the walls since they are exposed to the attic which is a giant hot box. Our old home had blown in insulation. It was horrible. I'm not a fan. I'm much more likely to use rolls.
thanks. Since the entire second floor is surrounded by attic, and the attic gets hot, I feel like the whole thing needs more. I've seen someone on here talk about having 24" of insulation in their attic. In my case, if I want that route, what would be the point in having something like R75-R80 on the horizontal surfaces and then only having 3.5" of R11 on the walls. So far this year, we've been lucky with cooler than normal temps, but before too long it's going to be July and Aug and then it's going to suck.

You can make your 2x4 walls into 2x6 or more by scabbing on additional wood to existing studs .

1. You have to add/increase your attic ventilation . Without it you are fighting an uphill battle .
2. If you add soffit vents and a ridge vent you can add radiant barrier to the roof structure . As an example if your roof trusses are 2x4 stapling radiant barrier creates 3 1/2" troughs for the cool air ( relatively ) to enter the soffit and exit the ridge . The barrier also radiates some heat away from the attic space .
3. Can't stress enough about sealing all leak paths . Any leak path allows heat/AC to escape and be replaced by what you are trying to " condition " against .

Your walls are probably "average" but your ceilings are way below average based on the pics.

If you can match the shingles close you could remove the ridge cap and have ridge vent installed to help with ventilation. You'd have to remove the cap, cut the roof about 1.5" to each side of center to provide air gap, then install ridge vent and then the ridge cap. Probably not the most cost effective way of going about it but an option.

Right, I get it. The house stays remarkably cool and comfy without the AC having to run constantly (which is a pleasant surprise), but I think the house has a lot of leaks. Hell, I know that I can see light under the front door and around the side door. I need to get those two spots sealed off for sure. The missus wants to seal up the side door and replace it with a window. (there's a second side door that we would use) So I guess that's got that door covered. The Front door is going to require a little repair of the threshold.

The "good" news is that a new roof is in our future. And usually a hip roof isn't a good place to install a ridge vent, but since we have the east/west facing dormers, we actually have a nice long ridge to work with. I'll probably wait and let the pros install the ridge vent when we get a new roof (probably within 1-1.5 years) at most.

PIR insulation boards

They give double the insulation value per thickness than fibreglass rockwool rolled out insulation

https://www.panelsell.co.uk/cavity-insulation-value-comparison

If you're fitting a new roof then it would be a lot easier to do the new insulation then

May I ask what's the hate towards spray foam insulation.

This is what I was going to do to my house

You got me wondering

We have no soffits to add vents in.
So I had something like this added

https://m.youtube.com/watch?v=sUaYv-cGxro


https://m.youtube.com/watch?v=JMdaGiRnog8


combined with the existing ridge vent it definitely helped cool the attic

From a certain point of view, I'd love spray foam. When done right, I suspect it's the most efficient insulation available at a reasonable price.

From my point of view, spray foam is like a started that's installed under the intake manifold of a V-engine. It's great when it works, but then if you've got to get into the walls to do any electrical or plumbing or any work on drywall, I assume it's a nightmare. And for me at least, since this home is 100 years old and likely to require maintenance on all sort of things, I don't want to make it difficult for myself.

I think that if you were building a new home, it might be great. You'd probably want all electrical or other sorts of cabling installed in conduits and plenty of conduit available in case you ever want to install other stuff. If I were building a new home, I'd wonder about lining walls with plastic or something so the foam isn't actually gluing the entire house together (again, making the inevitable maintenance a nightmare).

But I've never dealt with spray foam, so maybe I'm completely off base. I'm doing a lot of ASSuMEing. (misspelling intentional)

Do they do blown insulation in Texas? That's the way we insulate from cold in the north.