Home cinema room build - pro with some am

[CharlesElliott]

I thought some of you would be interested in our cinema room build. We moved into our house in 2019 with the intent of refurbishing it - we did the ground floor in 2020, the first floor in 2021 and then not a lot in 2022 - so 2023 is really the final phase and the more fun stuff. Our house in two storeys but with ‘rooms in the roof space’ which, in our case, actually means a Mansard roof with a single large room the full size of the floor, minus the eaves. The fact that this is already a ‘habitable room’ makes things easier from a Building Regs point of view. We are planning to sub-divide this single large room into four new rooms and a landing - the cinema room, a games room / kids room, a guest bedroom and a bathroom.

Although the cinema room spec and equipment is very much ‘pro’ as we are working with a specialist company, some elements are quite ‘amateur’ - I am doing all the architectural drawings and hiring the contractors to do the work, except the second fix and equipment install for the cinema room which will be done by the experts.

[CharlesElliott]

So this is the area we are starting with. Two sloping ceilings certainly not ideal, a window within the dormer and a skylight.

Edited by CharlesElliott on Saturday 18th February 17:53

[CharlesElliott]

Lots of options for layout were explored, but it the end we settled on the below. A new wall constructured in front of the rear wall to house the screen and speakers, and gain enough height with respect to the sloped ceiling. The rack will sit behind a door to the left of the screen. The projector will be at the rear of the room and will sit in a box that actually extends into the bedroom behind to get the throw within an optimal range. The rear seats will be on a raised platform and will be cinema style, with a sofa in front on the floor. We were advised - multiple times! - that this would result in a compromise with the rear seats further back than optimal and the fronts a bit too close, but we wanted to be able to seat more than four so that's it. Screen size is nominally 2690 wide but we will confirm once everything is built.

[CharlesElliott]

Panamax said:

Surely understatement of the year.

Also the screen's going to be 1.5 m high. People in the front row are going to crick their necks looking up at it.

Centre of the screen is ~920mm. We haven't lost too much if the front row isn't used, we just end up with one row. But I bet that sometimes, we use the front row.....

[CharlesElliott]

justin220 said:

Nice project but unless I've read that wrong, that won't be pleasant viewing on the front row being that close to such a big screen.

You might be right - final screen size still to be confirmed and if we don't use it, then we won't actually have lost anything.

[CharlesElliott]

justin220 said:

Have you ran your distances and screen sizes through any of the online calculator?

There is also a handy riser height calculator if you need, which varies quite a lot depending on screen size, seat height and distances

The screen / speaker locations and the riser are calculated and specified by the design company but.....if I run it through Carlton Bale's calculator, the front row is about 8cm too close to meet THX standards - so not much in it. And we may tweak the screen size yet.

[CharlesElliott]

The walls / ceiling will be made up of a sandwich of acoustic plasterboard, SY70 and OSB. On top of that there will be sound diffuser panels and speakers and then everything will be covered with a fabric track system.

[CharlesElliott]

Panamax said:

I'd tweak the projector into the bin and go for a TV of suitable size, but that's just personal opinion. In one of our rooms we watch a modest 65" from 4.5 metres and it's absolutely fine, so you have massive scope to flex your set-up.

IMO if you go too big on sound you'll overwhelm that room - there's not a lot of ceiling height. Make sure it sounds good at low level and not just when it's shaking the foundations.

thanks - will definitely be looking at all sound levels. The ceiling height is standard 2.4m (excl the sloping bits) although I agree that that picture makes it look lower. The current plan is for the screen to be 2.35:1 ratio (Panavision / Cinemascope) rather than 16:9 as films will be the primary source. Can still watch 16:9 but it will have black bars at the side.

[CharlesElliott]

Digger said:

Or both - have a retractable screen?

Yes - could do. But quite a lot more cost.

[CharlesElliott]

With the AV company having drawn the finished room plan, I needed to draw the build plans that take into account the existing large room and account for the wall build up (which is up to 86mm in total) for the carpenters to do all the studwork. There is also going to other rooms up there so this is part of a bigger plan. Here's what I have come up to allow the carpenters to get to work.

[CharlesElliott]

OK.....so let's get building.

This is the overall plan and speaker layout.



Here is the screen wall in progress. The centre speaker is positioned just to the right of picture centre. On the left is a door that will provide access to the rack and behind the screen wall.



And here is the platform on which the rear seats will sit.



Next up will be wiring and all the cutouts, which will be quite a task.

[CharlesElliott]

I'm still going! The electrician has been and we have the wiring in. There are

3 x front speakers, plus sub
4 x ceiling Atmos speakers
2 x side speakers
2 x rear speakers

plus lighting (walls, ceiling and floor), AV cables for the projector, network cabling for a switch.

In addition there is lighting and blind control from Control4. All of the equipment will sit in a rack behind the access door in the screen wall. The old skylight in the ceiling will be boarded over.







Next up is boarding and wall treatment.

Edited by CharlesElliott on Thursday 4th May 20:06

[CharlesElliott]

Griffith4ever said:

Looking good!

Thanks. The screen size and location were all calculated professionally so I trust them! Both rows are within the recommeded viewing angles, the front at the upper end and the rear at the lower end.

We are going with a Sony VPL-XW5000ES 4K laser projector. They've already tweaked the screen size (upwards) based on the throw - to get more distance, the projector housing actually protudes into to the bedroom behind, but will be covered with units so won't be visible.

ETA: Correct the projector model

Edited by CharlesElliott on Sunday 14th May 12:22

[CharlesElliott]

Now onto building out the wall structures, primarily for mass and damping. The spec is 15mm acoustic plasterboard (for those walls that aren't already plasterboarded), Tecsound SY70 acoustic mat - which is *really* heavy - and then 18mm OSB on top. The screen wall will also be covered in OSB at the rear and filled with acoustic insulation.

I have blocked up the skylight with acoustic plasterboard.



Screen wall in progress, filling up with acoustic insulation. The ducting / outlet on the left is from the AC unit that will heat / cool the room and the doorway underneath it will be a removable planel behind which the rack will sit.The three yellow rectangles are showing the front speaker positions, with the sub going in the bottom right of the wall. The screen will stretch from the right side of the left speaker to the left side of the right speaker.



The rear wall covered in Tecsound, with the speaker cutouts and the projector box.

[CharlesElliott]

dickymint said:

As regards lighting have you considered Phillips Hue Sync Box and lamps?

Our lighting is on the subtle side and will be Control4 driven. All those LED strips etc are cool though.

[CharlesElliott]

At this point I started to run out of time and motivation to continue doing the work myself, and also ran short of skill when sticking Tecsound to the ceiling neatly! So I called in some more pros to finish off the building work.

This picture shows the buildup well, the front wall (where the screen is going) has just acoustic plasterboard on it, then you can see the sloped ceiling which has plasterboard and Tecsound, then the ceiling itself which has plasterboard, Tecsound and OSB. One of the other challenges was that the transitions from walls to slope to ceiling were all curved and this really needed to be squared off to allow the fabric track system to be fitted. That was acheived with battens to straight line over the curves.

[CharlesElliott]

The final screen size is 2820 visible (2900 incl frame) x 1586. That's around 127 inches diagonal.

[CharlesElliott]

Griffith4ever said:

CharlesElliott said:

The final screen size is 2820 visible (2900 incl frame) x 1586. That's around 127 inches diagonal.

That's going to be great , particularly at 2.35:1 . I'm 135" 16:9 and its epic.


btw: I dont' think the comment above was aimed at you.

I did have to read it twice, but I got that. Anyway, I'm thick skinned!

In the end we went with 16:9, partly because the projector doesn't have switchable ratios and it is already expensive enough!

[CharlesElliott]

Crackedwinscreen said:

Good work Sir, I’m sure it will be epic when finished.

I hope in years to come you don’t regret you didn’t sacrifice some of the bedroom/games room space to make the cinema a few m2 larger.

I must admit I am out of touch with projectors, so I had to google yours, wow, you will be able to charge guests with that set up

We are fortunate that this is all 'bonus' area in the loft space so there isn't too much compromise. I also got the projector model slightly wrong, but it does mean that the one we have is about 10x cheaper than the one I named originally, albeit still a fair chunk of money!

[CharlesElliott]

OK, so we are finished with the shell now. Reminder that we have 15mm acoustic plasterboard, Tecsound SY70 and 18mm OSB. This is the screen wall with the three front speakers - the screen stretches from the right of the left speaker to the left of the right speaker. You can also see the cut out for the sub on the right, and the front set of the height speakers in the ceiling. The 'door' on the left has the AC/heating outlet and will have the equipment rack below it.



And the rear wall with projector box and two rear speakers - plus the raised level for the rear seat row (and one side speaker).

Edited by CharlesElliott on Friday 19th May 20:55