What is the smallest room size for surround and Atmos?

[KollyKibber]

I'm currently in the market to buy a house and I would like to install a proper Atmos setup, probably 7.2.4.

What is the minimum room size I should be looking for in order to install this and have the full Atmos/surround experience?

 

[ryanosaur]

How many seats?

I use an 11x15' room, but there is precious little space for 2 side by side, and my Rears are wall mounted above a closet on the back wall. Front Speakers are about 7-8' in front of me, and my back is about 3-1/2' from the back wall.

It is very important in setting up Atmos that you maintain some amount of separation between the Bed Layer Speakers and the Atmos Speakers above.
I have not set up Atmos Speakers, yet, but will soon (hopefully).

All that said, if you are pressed for space, 5.x.4 is considered a little more useful than trying to shoehorn Rears into too small a space.

Given an opportunity to design an "ideal space," I would say a minimum of 14'w x 19'd would be far better for a small room for 2-3 people and a 7-channel Bed Layer. I would Rather a space about 15 or 17'w by 23'd with a minimum of 11'H ceilings and maybe 13-14'h if possible.

I know others will chime in, too.

 

[KollyKibber]

Ah, I knew I forgot that detail!

It would be for 2, but let's say x1 3-seater sofa to keep things simple.

I did consider that 7. speakers might be a difficult ask. I'll be lucky to find a house with a 23' long room in the UK!

 

[ryanosaur]

We all have issues we have to work around in this Hobby. Consider the width of a 3 seat sofa, room on each side to walk past +any additional furnishing that may end up there like a Subwoofer or end table or such...
In my case, My Subs are on the Side walls which is why 2- wide is difficult... but it is also my private space in the house as The Lady didn't want to convert the Great Room into a theater space.

Anyway...

Important considerations are to understand the ideal Speaker layouts for 5- and 7 channels and to give space around yourself as you don't want Speakers right up on your LP if you can avoid it.
Play around with a scratch pad and draw what a room may look like for you given some different common room sizes in your area.

Will you be using a TV? Projector? What size screen? All of that has an impact on how you set up the room as well.

 

[KollyKibber]

Good point! I live in the real world, not a speaker test environment and have to take other things into account (unfortunately).

I'll be using a TV, most likely a 65" LG G1 (or whatever the equivalent is when I actually move in).

I'm trying to justify the need for a room larger than 11' square; the standard sort of room size that I see here.