Aaaaand eight months later, here we are... I realize now why some of the build threads here are multi-year sagas!
Analysis paralysis got the best of me for probably 5-6 months while I waffled back and forth on various approaches to building the screen wall and trying to decide whether to do anything fun with the ceiling or just keep things simple. I ultimately pulled the trigger on building out soffits to add some visual interest with LED accent lighting and an integrated enclosure for the projector.
First, I had to decide on a target screen size. I'm limited both by the 10' width of my screen wall and the maximum throw distance afforded by the length of the room (max 12' after deducting the 18" lost to the false wall and roughly 24" from the back wall to the projector lens). I knew I wanted 16x9 in order to maximize screen area given the limited width. I landed on a 120" diagonal screen, which I think is realistically the largest screen I can fit in my room. I toyed with going all the way up to 130" -- this could in theory have worked with my Epson 8350 since it has very flexible zoom and shift capabilities, but it would have been operating at the very limits of the projector's range and I was too worried about backing myself into a corner with respect to future projector upgrades. Even at 120" I'm anticipating that a significant number of projector options won't be viable, and I may need to stick with Epson moving forward to make it work.
I went DIY for my screen this time around. While I loved the fit and finish of my aluminum Carada Criterion screen, the bang for the buck of DIY made too much sense in this case to justify spending the extra cash on a commercial screen. I ordered Center Stage UF material from Seymour AV, as well as their Baritone velvet to wrap the frame and surrounding wall panels. After striking out at all the big box stores, I ended up sourcing some nice 7/8" poplar boards from a local hardwood speciality store for the screen frame and surrounding fabric panels. I used 3.5" boards for the screen frame, and had the supplier chamfer the interior edge for me in their shop. After measuring and re-measuring about 85 times, I cut the boards to length and mitred the corners myself. I followed these instructions
from Seymour pretty closely (without the the fancy biscuit joints) to wrap and assemble the frame. I've not yet attached the screen material itself, as I don't really have anywhere to store the finished screen during construction. I'm going to wait until drywall and the other messy stuff is done before finishing it off.
Screen wall construction
I had originally intended to follow BIGmouthinDC's minimalist approach for the screen wall, but ended up deviating a bit for a few reasons. I did construct two "goal posts" with a crossbar to hang the screen frame from, but mounted the goal posts flush with the side walls rather than freestanding toward the interior of the stage like BIG usually does. This made more sense in my case because including the frame, the 120" screen would occupy 112" of the available 120" width of the screen wall, leaving 4" on either side to be filled with fabric panels - I wanted the goal posts to support both the frame and panels and not to interfere at all with placement of speakers behind the screen fabric. Additionally, I wanted the screen wall to support much of the load of the soffit above the stage rather than simply hanging the soffit frame off the ceiling joists, which called for beefier construction than the 5/4" pine boards BIG recommends.
I ended up with 6.5" wide goal posts consisting of sistered 2x4 studs with spacers in between. The outside studs run floor to ceiling, and the inside studs are 13.5" shorter to support a flat 2x4 header running between the posts. The sole plates of the posts are screwed into the stage decking, and the outside studs are screwed into the adjacent walls. I employed steel channel on the ceiling simply to keep everything aligned and screwed the channel into strapping boards in the ceiling.
I then attached a 2x4 "railing" to the studs in the back wall with 4" framing nails, at the same height as the header. I cantilevered 2x4 crossbeams 16" on center across the top of the railing and the header to form the bottom of the soffit, and added 2x4 uprights secured to the ceiling with the steel channel. The soffit is 12" high to match the existing soffit that conceals the duct work above the bar area, and 36" deep (of which 18" will be visible in the room). The uprights are set back 6" from the front edge, creating a tray for the lighting strips.
This design seems to have worked out pretty well, with the exception that levelling the soffit was a huge pain in the ass -- I put the crossbeams up and ripped them down probably three times before getting it straight. I finally picked up a cross-line laser level and mounted it to a camera tripod stacked on top of a bunch of storage containers in order to beam a line across the face of the crossbeams. I then cut a ton of shims of varying widths from scrap 2x4, and sandwiched the shims between the crossbeams and the header to bring all of the crossbeams into alignment. This was tedious as hell but the end product turned out okay (I think...).
Here's a photo of the screen wall and soffit before the crossbar was installed:
For the crossbar, I face-mounted a 2x4 to the goal posts using low profile joist hangers. The crossbar is set back 3/4" from the front surface of the goal posts in order to fit the french cleat (cut from a 6' length of pine 1x4) while allowing the screen frame to lay flush against the goal posts. I glued and screwed the other half of the french cleat to the top member of the screen frame.
Here's a photo of the screen frame hanging on the crossbar:
I used the same 7/8" poplar to construct fabric panels for the remainder of the screen wall. I used 2.5" boards for the frames above and below the screen. These panels are 10' wide, so I added two 4" mid-span supports. I secured the corners with steel L- brackets and the mid-span supports with steel T-brackets. For the left and right panels, I simply cut solid 4" wide boards to length. I wrapped everything in the same Baritone velvet that I used for the screen frame. The frames were designed to friction fit and they stay in place very well without any fasteners. I may still add a bit of velcro to play it safe.
One annoying mistake I made here was to make the top and bottom panels the full width of the screen wall. While I did leave 1/8" clearance when cutting the frames to accomodate the velvet, and the fit is great once the panels are in place, getting them into place is pretty painful. I have to try to line the panels up and maneouver them straight back more than 3', which is tough for one person given the 10' width of the panel. The fact that the drywall isn't perfectly straight exacerbates the problem and I have to apply a bit of force to push past the imperfections, which scuffs up the walls a bit. Not a big deal during construction, but once the final paint is applied to those walls it's certainly going to be annoying and I'll likely avoid removing these frames unless absolutely necessary. If I did it again, I would make the top and bottom panels the same width as the screen frame, and run the left and right panels from stage to soffit. In hindsight, this approach would have made it a lot easier to move the panels around without damaging the walls. But, I'm out of velvet, so it's not going to change now.
Here's a photo with all of the fabric panels in place around the screen frame:
The velvet really does it's job inhaling the light, making it tough to get a good picture -- this one almost looks photoshopped. I can't wait to see it with the screen fabric in place and the lights off.
Rear soffit construction
I then turned my attention to the rear wall, where I planned to build a similar soffit, 12" high and 24" deep with the same 6" lighting tray. I also wanted to integrate an enclosure / poor-man's hush box for the projector. I started by ripping down the projector mount and mounting plate shown in my previous posts, and cutting a sizeable hole in the ceiling drywall to determine the location of ceiling joists to secure the soffit to.
At this point, I was still planning on using my Chief RPMAU mount inside the enclosure, as I felt it would be superior to shelf mounting with respect to being able to accurately dial in the roll, pitch and yaw of the projector. So, before closing up the ceiling, I installed additional blocking between the joists, moved some less than ideally located electrical lines out of the way as much of possible and fashioned a new mounting plate out of 1/2" plywood that would sit flush with the surrounding drywall. I started with a 24x24" sheet and used a jigsaw to cut holes for the conduit and electrical outlets. I screwed the plate into the new blocking, giving me a nice uniform surface to attach the mount to, with confidence that it could easily support the weight of the projector. It turned out that this work was all for naught in the end -- even flush mounted to the new plate, the RPMAU still dropped the projector too far from the ceiling to fit nicely within the soffit enclosure. My Epson 8350 would have barely fit (maybe 1/2" to spare), but after researching some of the popular 4K projectors and finding that they were all 1-2" taller than my 8350, I realized that I needed to decide between using the Chief mount or doing the soffit enclosure. I chose the latter, and now need to find a buyer to offload my virtually unused RPMAU.
Moving on to the soffit itself, the first thing I did was nail another 10' long 2x4 railing to the wall studs. Then, I cut two 4' lengths of 2x6 and secured these with 3.5" lag bolts to the one ceiling joist that fell within the interior dimensions of the soffit. I would have preferred to use 2x4 here, but the location of the joist was such that I needed the additional 2" to span the gap between the joist and the desired location of the front of the soffit. Otherwise, the soffit would have been 22" deep rather than 24", and I wanted the full 24" to ensure that a deeper projector would easily fit within the enclosure. I used 2x4s for the uprights and crossbeams, and secured these to the railings using 3x3" steel corner brackets. I used 2x6 crossbeams at the edges of the projector enclosure, providing a 2" lip for the projector shelf to sit on. I also used beefier 5x5" corner brackets to secure these crossbeams and their respective uprights. Finally, I cut interior walls and a shelf for the enclosure out of 1/2" ply. Levelling this soffit was much more straight forward with the laser level and corner brackets, no shims or other hacks necessary.
I popped the projector into the enclosure temporarily and fired it up to ensure that the throw distance and vertical shift calculations I had done were reliable -- all systems go!
Sidewall soffit construction
With the front and rear soffits in place, I moved on to the sidewalls. My plan here was to extend the 6" lighting tray to create visual symmetry around the perimeter of the theater area. Unfortunately, this plan fell apart relatively quickly and I'm still figuring out how to proceed.
The exterior wall was relatively straight forward - I nailed another 2x4 railing into the studs, and attached stubby 2x4 beams to the railing with the same 3x3" corner brackets. I used the laser level to ensure alignment with the crossbeams on the front and rear soffits.
I was going to attach a 2x2 nailer at the top of the wall and then install drywall or fabric frames on the vertical surface above the tray, to match the treatment of the front and rear. Before finishing this off, I started working on the other side of the room, which is where the plan fell apart. On this side, I needed to attach the lighting tray to the vertical surface of the existing soffit rather than to a full wall. I had stupidly assumed that the soffit was framed conventionally with wood the same as the rest of the house, but when I broke out my studfinder to locate the uprights to attach my 2x4 railing to, I couldn't find a thing. After many profanities, I cut a hole in the drywall to figure out what the heck was going on. As it turned out, there WERE no uprights! The builder had used steel channel and studs like so:
I don't think there's anything particularly wrong with this method given the intended purpose of the soffit, but it certainly makes my life more difficult because I don't have anything of substance to carry the load of the railing plus nine 2x4 beams to support the tray. I would have been okay punching some beefy toggle anchors through steel uprights, but there aren't any -- the only thing behind the railing location is 1/2" drywall.
I'm still kicking myself because I should have anticipated this much earlier in the build and confirmed what was there before getting everything else done. I thought briefly about tearing out the soffit entirely and reframing it with wood, but all of that extra work for a minor aesthetic improvement was pretty damn unappealing. I also didn't know if I would need to pull a permit to do it because the soffit houses a couple of LED potlights. Instead, I rage quit and tore down the tray I had just installed on the other side of the room.
Back to the drawing board. I'm still thinking of alternative approaches to extend my tray around the sidewalls, with a low enough load that I can feel confident attaching a ~12' run to a single piece of steel channel that is only supported vertically by a sheet of drywall. If anyone has any suggestions on this front, I would be very open to hearing them! If I can't figure anything out here that feels right, I'm going to scrap the tray on the sides and just stick with two independent lighting strips in the front and rear, which sucks, but I suppose won't be the end of the world.
In my next post, I'll detail my plans for:
- Finishing the projector enclosure (including active temperature control)
- Finishing the lighting tray and soffit surfaces
- Acoustic treatments for the soffits and screen wall