r/Insulation

I just built an A-frame and have been struggling with this decision. There’s a 21/12 roof pitch, 3 foot crawl, ERV system installed. The quote for RW was about $34,000 and the quote for HDF was $17,000. I’ve got a Midea mini split system that’s sized to heat/cool the entire home snd then a wood fireplace. Will I regret not choosing RW later? We are paying cash and don’t have a loan so costs are at play.

Hi Reddit community,

I am feeling a bit overwhelmed choosing between foam or batt insulation for my detached two-car garage and sunroom (converted patio) .

The house is a 1957 mcm ranch in DFW.

The garage is just a shell. I want to have it insulated w/ sheetrock up to the sloped ceiling, allowing space between the ceiling and beams to maintain the height. This will be an air-conditioned art studio.

The sunroom ceiling backs up to the roof decking- there is no attic space above it. It gets pretty hot in there.

Two different contractors have told me either to do batt or foam- each preferring one over the other.

The one who prefers batt said foam conceals leaks, doesn't let the house breathe, and is flammable.

The one who prefers foam said foam is much better for conserving warm or cool air in the house.

They are both very similar in price and willing to do either- I just don't know which to choose for each space.

I've been reading more about the need for the roof to be ventilated above the insulation. So many variables to consider!

Thanks so much for any advice/insight you can offer!

New build, mostly being done by contractors but I’m doing some of the easier stuff myself including insulation.

Problem #1: So for the main floor I’m using Rockwool batts, and planning it out I just noticed one of the corners isn’t quite a California corner. They blocked it out as one, but looks like the last board of the adjacent wall stops right in the way.

What’s the best or most reasonable way to insulate that corner?

I’ve thought about pulling the one board, putting Rockwool in, and putting the board back. Or, drill 3-4 3/4” holes in it and fill it with canned closed cell.

Problem #2: Similar to problem 1, they’ve blocked several
spots for the interior walls to fasten to the exterior (see 3rd pic) that have a cavity behind them. Unfortunately I think these are loaded with nails, so the spray foam is probably the easier option there.

Attached sheathing is Zip System if it matters.

Electrical wiring is laid down over joists of attic, so I feel my options for improving the insulation are limited. Is my only option to remove the old and add new blown in insulation?

Attached photos are where the basement connects to the front porch and air seems to be getting in, along with the bottom of the first floor.

I can see some insulation at the top of the foundation (looks a bit shitty to me, but I know nothing), and none on the floor itself.

From the little I've read so far, it seems like my options are:

- better seal the foundation

- insulate the floors better (sealing gaps, insulating the floor itself?)

- area rugs on the flooring itself

Please educate me 🙏