Before you spend all that money, have you looked into properly insulating it? What kind of insulation do you have in the walls and the ceiling above the room. I have a room like this over my garage and was constantly thinking of adding some specific room solution for it. It ran 25 degrees different in the winter and 20 in the summer from the rest of the house. Adding a new furnace with a vs blower in basement (had an old 60 yr old gas hog) brought me to 10 degrees closer to the rest of my house. After alot more research i found that uninsulated kneewalls to be the main problem with these rooms. I cut 3 2.5 inch holes in the kneewall that ran 5.5 X 20 feet and saw I had a mini attic space there about 2 feet wide at bottom and .5 feet at top with No insulation. (imagine a long triangular wedge) That empty space allowed any heat gain from the front slope of the garage to go right to the room negating any ac or heat from the room in winter to just seep out wasting my money. I pumped 5 bags of cellulose last January into this space and then patched the holes. (Ceiling was done b4 new furnace to R50) Immediately i noticed that this room went from minus 15 degrees from the rest of my 2nd floor to within 2 to 3 degrees difference which is tolerable. Im even using the room now in the summer with no diff in temp from the rest of the ac cooled house which i havent ever been able to do before. Total cost to insulate the kneewall was 80 bucks and took me bout 10 min drilling holes 15 mins pumping insulation and 30 mins patching. I painted the patches the next day.

chery2, Every time I clean & organize our basement (after procrastinating for weeks at a time) it honestly always seems so daunting. It's THE LAST thing I ever want to do. And I'm not even organizing so I can gain space for myself. I just do it b/c I have to be able to access some of the stuff from time to time and before you know it you can't even walk through there (seriously!). But EVERY time it honestly only takes me ~2-3 hrs. Not a lot of time - even if it's completely unorganized with piles of stuff everywhere. I just always think it's going to take forever based on what it looks like. First thing you need to do is decide on a place for all of the stuff you rarely use like xmas and easter decorations- do you have an attic, a basement or a garage? Then try to org the rarely used stuff in piles. Makes piles all over the room but just get the stuff together that belongs together. Then write a list of your piles/categories and next to it write the approx size bin you think you'll need (with room to add if necessary). Then go buy some bins. Put everything in the bins and label them with a large marker and decide where you will put them. Hopefully you can stack them in the attic, basement or garage - especially the stuff you rarely use. Get it out of there!!! Who wants to have their 'sanctuary room' piled with stuff you rarely use anyway. Then for the stuff that you want to keep in that room, you'll now have freed up some space to use the pieces of furniture/storage you already have to organize it. The important thing to remember is it will probably take you a lot less time than you think to clear out that room. It will seem daunting but you can do it. Once you start, you'll get your momentum and you'll want to finish. That's your sanctuary room - every girl's dream! If you think you're worth it and deserve that space then you will make the time. I know you can do it!

do a google search of family room over garage. you'll read of the heating cooling issues of these spaces. as they are surrounded on six sides by extreme attic temps. you'll need to not only insulate, but air seal the walls shared with attic space. I use a foam sheathing board installed over insulation in stud bays. Then continue the foam sheathing between the floor joists to the attic floor. as detailed on page 6 of this pdf file. http://www.southface.org/wp-content/uploads/2016/07/georgia-code-iecc-appendices-2009-1.pdf without this additional insulation/air sealing these rooms are difficult and expensive to heat/cool. IF your hvac system was sized including this bonus room. then you'll have capacity, for both supply and return for this area. once you address the heat gain issue as mentioned above, then it will be much easier to condition this space. one either addresses the issue, or throws more $$ into a/c heat for the room. which will cost you more in utility bills & lack of comfort. in that google search you'll see a 2014 green building advisor link. read the comments of the energy rater in that discussion. best of luck

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