First off I’m not a frequent poster to this forum but a long time AVS member and have had 2 FP theaters in two different homes over the last 14 years. My first theater was more of an on going work of love as the rules were not nearly as defined 14 years ago and technology has changed a lot over that time. I have learned a lot about what I personally like in HT and it is not always what you see showcased in the HT of the month threads. I’m not opposed to these beautiful dedicated works of science and art, actually just the opposite as I admire the attention to detail and the end results are amazing. I just could one never afford the full-blown theater and two they wouldn’t fit into our lifestyle at all.
The first step I would take if I were you is to take a step back from the details and think about how you and your family and friends will enjoy the area. Picture yourself in the room with your kids watching family content. Picture the two of you watching something together after the kids are down for the night. Picture you and your buddies watching sports or you both and another couple watching a movie. You want the room to be used in a way that’s maybe is different than going to a commercial theater.
For us we eat and drink in the TV room as we call a lot. We like the social setting of all being in the same row whenever possible with both friends and family.
Just some generic thoughts before opinions on details.
First opinion. Never put your equipment in the front of the room on the screen wall. That’s a carryover from TV and the lights on the equipment will be distracting along with the cable run to the projector will be long. I like the equipment out of sight in the back of the room or to the side.
Second, get rid of the storage area or figure a door into it that doesn’t enter into the theater. The door takes up screen area and I assume there is other storage in the home and closing that off was an after thought.
Third, familiarize yourself with presentation methods CIW, CIH, CIA, CIH+IMAX and even others that use variable areas as I do. The zoom on your projector is one feature no TV will ever have, and proper immersion makes all the difference in the world in a theater. When you go to a commercial theater once inside the first thing you are confronted with is where to sit. If alone you pick your favorite seat if with others the committee decides. Your taste for immersion is different than others and I can almost guarantee once you have a home theater for a few months yours will change. At least that’s true for most people. You are used to TV you go to the movies a few times each year, once you have a theater you will be watching a movie or two daily perhaps. Resolution of media and projectors keep getting better and there is to be a push to deliver more IMAX1.89:1 and IMAX like content (Game of Thrones) etc in the future. I would highly recommend some presentation that allows for IMAX1.89-like presentation with proper immersion. Watch the HD-BD or UHD-BD of Dunkirk as one of your test movies when you are playing with projecting to the wall and moving your projector around during the test phase, you will get what I’m talking about.
Lets just say you adopt CIH+IMAX as your presentation method. You say you like to sit in the middle of a theater and that would equate roughly to a seating distance 2.5 times the height of the CIH image for (scope 2.35 and flat 1.85 movies) then any IMAX content would be the width of scope but taller. That is how directors intend these movies to be watched. They don’t care about what level of immersion you like but in relationship that’s roughly how commercial theaters would show them or how many here think they should be shown. The extra vertical immersion in a movie like Dunkirk is so key to the spectacular image we are to see. That’s your front row. Now you can do the math but the second row at home isn’t like the next row back in a commercial theater. At home the proportion is greater because of the smaller screen and your second row will be likely 4 times the screen height seating distance and like the back row in a real theater.
For that reason and others in my room I wanted a single row of 6 seats rather than 2 rows of 3, or maybe one row of 4 than 2 rows of 2 etc. Doing that avoids building risers allows for a larger IMAX screen as heads are not in the way and IMO being more off axis isn’t as bad as having under immersion. I turned my room 90 degrees in fact and useed the longer wall for the screen. Some will tell you correctly doing that messes with the audio and will be correct to some extent. Another thing to conceder when mocking up your space is how sensitive you are to perfect audio.
Lastly I’m not sure what to tell you about should the builder complete the room or not, because I don’t know your level of perfection you are going for. If you plan on putting the kids to bed and going down and showing Iron Man in full theater mode with big subs then you should wait and really study sound transfer and just maybe after doing all you can you will still wake them up. We don’t have our modest room treated much different than a regular room and we do play it loud but we do it when we conceder others in the house. I even often watch late at night with headphones. If it was me and I have hung 1000s of sheets of drywall in my life I would have them finish the room minus the storage room if that’s an option.
It is hard to advise others and much easier to work with them thru the issues as you figure out what they want. Don’t be in a hurry to finish the room figure out what you think about presentation and select a projector that works best with what you like throw, zoom, offset, and all the rest. Then play with it in all the methods with some lawn chairs for seating. The time that saves you in the end will more than equal out any extra labor and materials.
Good luck its exciting doing a project like this.
Oh P.S. The new sound systems are pretty amazing I’m sure. I’m still 5.2 with very good quality large clear drivers and it makes all the sound my ears will ever need. Where you go with the sound is really up to your desires. With much of my content I actually like it best 2.2.