There is insulation between the garage ceiling and bedroom floor. Garage ceiling is about 14' high. Having to deal with getting up to those heights to then have to deal with the existing drywall seems like something that I can cause more harm than solve. I'll have to pull my diagrams from the builder, but I can almost guarantee it's not anything above a standard R-Value for that type of space. The home's exterior walls and the walls along the garage that are connected to the living area are only 2x4 frame so those likely have no more than R-15.

The mudroom from the garage feels like a furnace when you open the door so I have to assume the insulation there is doing it's job. What I'm looking to do is to minimize the temperature swings in the garage, by doing so making the demand on the ceiling insulation less. I.E. insulating against 90F temps, not 110F. ??

Yes, it would help with that.

I guess worst case, I only spend $300. Next stage is blowing the attic space to R-60, up from R-30.... Thanks for the time and input.

Cost and effort to insulate garage door? Any windows?

I still maintain you can add insulation to the garage ceiling more cheaply and to better result - seems you had your mind made up in your original post.

The walls and garage door are known areas of deficiency. I know there is backed insulation in the ceiling that is already under drywall and mud. While I'm pretty set in my course, if those with more knowledge than I have say what I'm doing won't effectively mitigate the garage temp then there really would be no gain in me insulating the 2.25 walls and installing insulating panels on the door. If I had thought about it, I would've went with the upgraded, insulated door upon build contract.

My master bedroom is partially over a two car garage. The garage was insulated when I bought the house. The garage doors are not insulated and not tight to the frame.

Insulating the garage will help but don't expect a noticeable difference. The insulation between the walls and ceiling between the garage and house should be the same as the rest of the exterior walls. In the winter the garage may be warmer than the outdoor temperature especially if it faces south. In the summer my garage traps a lot of hot air. In the evenings when the outdoor temperature drops, it still feels significantly warmer in the garage.

I would spend the $300 on the insulation just to make the master bedroom floor feel more comfortable. It is worth it in my opinion.

If you have insulation between the garage ceiling and the MBR floor I don't think insulating the garage walls/door will serve any purpose unless the garage is conditioned.

"If you have insulation between the garage ceiling and the MBR floor..."

More is better.

"More is better." True, but it depends where. Insulating the walls and door(s) of a non-conditioned space that do not abut a conditioned space will have little to no effect. More insulation in the ceiling space with a master bedroom above it will, of course, help (provided its not just compressed into an already fully-insulated space).

Sktn77a - "provided its not just compressed into an already fully-insulated space." is really the unknown. I'm probably going to be forced to approach the builder's insulation guys still working in the new phase to see if they can confirm the amount of insulation in the space between the garage and MBR floor.

Perhaps I'm trying to pursue the easy route because of my lack of experience dealing with trying to get up to the height and then dealing with the existing drywall.

"We have a brand new build with a HERS rating of 53................ The issue is the master is subjected to the added temp stress of both the hot summer and cold winters in Ohio."

How new? I take you've had at least 1 winter and 1 summer there already?

If the garage ceiling is insulated to its full depth then you'd have to add a false ceiling to increase it. Alternatively, you could remove the fiberglass insulation (I'm assuming its fiberglass) and use spray foam for added R value. Both of these involve a lot of construction, though, and would cost quite a bit more than your initial $300 budget. If the house is new and HERS 53, isn't your builder responsible for this issue? (A HERS 53 score is significant because it's a Presidential Award threshhold that builders tout when trying to earn your business!)

In most ways, this boils down to a cost now vs. cost later situation. For the long run, insulating and the more troublesome, air sealing of the garage is going to be a poor investment. Some of your heat and cool ends up there rather than staying in the BR. Keeping the door sealing is a maintenance item. If you don't want or need the garage to be more moderate temperature, I think that closing the BR off from it is a better idea than coupling the BR to the garage and "fixing" the garage. Another thing comes to mind is my sister's garage over BR, she hated the noise of the garage door opening. More insulation in between can't hurt that.

As a follow up to the original post, I did install R-13 in the exterior walls and in the space above the garage door to ceiling. While I still need to deal with the uninsulated garage door, the garage generally maintains +33F above the outside temp when we leave for work. We're also in the middle of the -7 to 15F temps in Ohio for the last week. Coldest temp in the garage has been 30F. Overall for about $105, I have to say it was worth it. I'll need to spend more to deal with the door, but after spending a week in AZ last month, the wife is now pushing to relocate, HA.

Talking it over with a friend a few houses over, he looked at what the builder installs in the garage ceiling. It's a small layer of spray foam (I'm assuming for sealing and fume barrier) and R-30.