Every now and again, there's a thread about what is an appropriate riser height. Unfortunately, there is no one answer that covers all situations. Everyone's setup is different, and requires a different answer depending on many different variables. Here's a fairly easy formula to figure the exact minimum riser height for your setup.

Riser Calculator (http://www.theater-calc.com/)
Courtesy of trunks in Post #2

First, take the following measurements in the same increment (e.g. inches):

S=Floor to screen bottom
H1=Height of seated front row viewers top of head
E1=Height of seated rear row viewers eyes (no riser)
D1=Screen to front row viewers eyes
D2=Screen to back row viewers eyes

Then, plug them into these calculations:

H1-S=V1
V1/D1=R
R*D2=V2
V2+S=E2
E2-E1=Riser height

V1=Vertical 1, V2=Vertical 2, E2=Back row eye level (with riser).

This formula uses a single height viewer in both rows. If you think you'll have taller people in front and shorter people in back, you might want to adjust the numbers slightly to compensate. You will probably come up with a number that seems too high. It is not. This number is the minimum riser height that will allow a person seated in the back row to see the entire screen, over the head of a person seated directly in front of them. Anything less, and some of the screen will be blocked.

Happy Building!

Rob

Rob -
I made a simple script based on this forumla.. I hope you don't mind.

thanks,
jake

www.theater-calc.com (http://www.theater-calc.com/)

Nice job, guys.

Jake,

Great job! That is absolutely fantastic! Anyone else think that this should be a sticky? Moderators?

Rob

I stuck it before I posted previously. Even added a lightbulb ! ;)

That is definitely a keeper if it works! Hall of famer.

Sorry, didn't see it. This is kind of exciting...contributing to a sticky. Woo Hoo!

Rob

Since I originated the particular discussion which resulted in showing the basic math followed by the helpful Riser Calculator, I'd like to see further adjustments, such as:
1. A variable number for the height of the seated rear row viewers eye
2. The picture actually changes as different variables are put into the calculator.
3. Assuming the height of the seated front row viewers eye is supposed to be 1/3 to 1/6 of the screen height, somehow add that.

Not being a programmer, it's easy for me to ask for something as complicated as this might become. In any event, nice work.

Sincerely, Take Aim

Take Aim,

Regarding 1. above, you can use any height you want in the "front row viewers eye" space. It's actually the rear eye height that you need . I simply called it that because I used the same seats for both, and used the front seats to figure the eye height, before I actually had the rear seats. As for the other two, that's all Jake!

Rob

Jake,

I realize now that my wording of the original formula might be confusing. If you agree, and would like to change the third line of your script to read "Height of rear row viewers eyes", with the tan line connecting the rear heads eyes to the top of the riser, I would change my original post as well. If not, I think people can figure it out.

Rob

Originally posted by robbyc30
Jake,

I realize now that my wording of the original formula might be confusing. If you agree, and would like to change the third line of your script to read "Height of rear row viewers eyes", with the tan line connecting the rear heads eyes to the top of the riser, I would change my original post as well. If not, I think people can figure it out.

Rob

Done



2. The picture actually changes as different variables are put into the calculator.
3. Assuming the height of the seated front row viewers eye is supposed to be 1/3 to 1/6 of the screen height, somehow add that.


I thought about this a little more, and since the room isn't drawn to scale, the second request doesn't do a whole lot for us. Now the third option is a good idea, but I would also need the screen height (and probably the room height) to make it work.
What I would like to do is make a new calculator, this will be much more complex and take some time, but here are my ideas:

this will require room height, width, length. It will make a recommendation for number of riser levels, but allow the user to select how many they actually want (IE room size will allow for 3 riser levels, which script recommends, but user only actually wants 2 in room...) it will have defaults for several items, but all of course are user changeable: 4' riser for standard theater seats, 5' for nonreclining chairs/sofa, 6' for recliners (In my experience these approximate numbers usually work pretty good).
It will then give recommendations for riser height/placement, screen placement and maximum size (limited by riser visibility, or SMPTE/THX viewing angle for closest row)
Any recommendations? Hopefully I can have this done in a week or two (don't have a lot of free time)

Originally posted by trunks
Rob -
I made a simple script based on this forumla.. I hope you don't mind.

thanks,
jake

Riser Calculator (http://www.cinegi.com/cgi-bin/riser.cgi)

Very nice guys!

Just one comment.

The brown dimension line associated with the text "Height of rear row viewers eyes " are drawn showing the height of the FRONT row viewers eyes.

Larry

Originally posted by LarryChanin
Very nice guys!

Just one comment.

The brown dimension line associated with the text "Height of rear row viewers eyes " are drawn showing the height of the FRONT row viewers eyes.

Larry

Sorry, you must've been using it right as I was making the change. Should be fixed now.

-Jake

I changed the original post to reflect the new script. Thanks Jake.

Rob

Rob,
Thanks very much for getting the formulas to us and adding to our knowledge.
Trunks,
Thanks for making it use friendly for some of us.

Art

robbyc30
Thank you for taking the time to post the formula

trunks
Thanks to you as well for writing the script so as to input info and get dimensions on the fly.

Best regards
Don

You're very welcome. Glad to be of service. With so many people here, with so much great information, and giving such helpful advice, this makes me feel a little less like a mooch!

Rob

Ok... I'm at work and don't have exact measurements in my brain, but that is just down right cool!!! Thanks!

I spent lots of time before construction drawing sight lines etc... to be sure I got the riser height right.

I went and plugged in my numbers to compare with what I came up with in real life and your calculator was only one inch off of what I came up with for my riser.

I can see this being very helpful to everybody starting to plan their theater. Saves time.

Just make sure your eye, head height is the same as the defaults set here. Change them to be more accurate.

Very good job guys.

Jeff

Very nice. I built my riser 10" high and my second row is about 3 inches to low. Your calculator says it should be 13-1/2".

Just Wow! Thanks! I've just started building. This will surely be useful.

Nice Job! Adam.

Hi,
I just plugged my numbers into the Riser calculator and it came back with a rear riser height of 2.25 inches. Anyone else get such a low measurement?

Here are the numbers I used:
Floor to bottom of screen 26"
Height of seated front row viewers top of head 45"
Height of rear row viewers eyes 50"
Screen to front row viewers eyes 13' (feet)
Screen to back row viewers eyes 18' (feet)

Minimum riser height 2 1/4"

*I can't really put my screen any higher. Maybe 28". And the screen to front and back row eyes doesn't have much room for movement either.

My front (non-riser) row is going to be Berkline 094's (http://www.av-outlet.com/en-us/dept_317.HTML) and my rear (riser) row is going to be Berkline 088's (http://www.av-outlet.com/en-us/dept_323.HTML).

Do any of my numbers look off?

Thanks!

Your numbers sound very similar to my room and my riser is 16" tall. A two inch riser does not sound big enough.

I put my numbers in to play around with it and I varied the front head level by 5 inches or so and got the number to lower to something like you were getting.

My advice is to not guess where the head levels will be. Go measure this if you have access or have others that own these chairs do it for you.
Second, err on the side of taller if you have the head room in your room. I would go with at least 12 to 14 inches or even up to what I have at 16 inches. I can tell you, when seated in the back row and a full theater, everybody reclined it is perfect. Any lower and I would have visability issues.

Also get some graph paper and draw it out. Put everything to scale and draw sight line diagrams and make sure they clear the head in front. I figured everything in the upright position and it worked out very good for me. Any lower and I would have problems and any higher and I would loose valuable head clearance.

My room setup is:

Berk. 090s

Front row at 12 feet
Second row on a 16 inch riser at 17 feet.
Screen at 24 inches off the floor.
Can't remember eye height but I think its right at 42 inches with my 090s. Add around 5 to 6 inches to the top of your head.

Good luck.

MoG,

According to your numbers, your rear row eye level is 5" higher than the front row top of heads height. Unless the seats on the 94"s are about a foot lower than the seats on the 88's, this isn't possible. Re-check your numbers.

Rob

Great work guys!

Thanks for your efforts

Regards

Ken L

I get a negative number on all of my results, any ideas why??

here is what I get:

Floor to bottom of screen 36"
Height of seated front row viewers top of head 42"
Height of rear row viewers eyes 52"
Screen to front row viewers eyes 9'8.5"
Screen to back row viewers eyes 14'4"
Minimum riser height -7 1/8"

Glack

Glack,

You seem to be making the same mistake MoG did. Unless your front row seats have a seat level drastically lower than you rear seats, the rear eye level should be lower than the front head level (because your eyes are lower than the top of your head). Your numbers indicate you already have about a 16" riser. If you do, and the 52" is including the riser, the calculator is telling you that it is 7 1/8" higher than it needs to be. If you go with the defaults (42" and 36"), you get 8 13/16", which is very close to 8 15/16" (16" - 7 1/8"). If you don't already have a riser, something is wrong with your measurements.

Rob

You are correct, I was placing the rear eyes where I wanted them and not at default height. I ran it again with the default settings and all is well

Thanks.
Glack

Did all the measurements this AM with wife seated staring at a level (good wife) and drew all out on graph paper. The answer I got was a 16" riser.

This afternoon I saw your sticky, pluged in the numbers and got 16 1/2".

Thanks for the very accurate caculator.

I am planning on making a 10" or 12" riser. My sealing is only 7 and half feet tall though. I would rather the backrow be looking down and over the front row. It will be 68" wide to allow full reclining. If you are going to do a riser shouldn't it be atleast a foot tall?

No. It should be as tall as it needs to be, to allow the rear viewers to see all of the screen, over the heads of the front viewers. If that's less than 12", then it's less than 12".

Rob

Yes, but for the cool effect of going up a step on to a riser just seems pointless if it is only 2"-6" tall. I want them to feel like they are really in a stadium seated theater. The illusion works better if it is atleast 10" or taller.

Joe,

As long as it's at least as high as it NEEDS to be, you can make it as high as think looks good. Keep in mind that most steps are around 8 or 9 inches high. If you go much higher than that, say 12 inches, you might want to put in a step, or it might look and feel too high.

Rob

Since I am an HT builder in the Midwest, and lot of my jobs are in basements, I get this a lot.

Your absolute FIRST concern is not to violate building codes or compromise safety. I have been doing LOS (line of sight) charts for multi-row theaters for many years, and I thank you guys for the application. Sometimes low ceiling height requires that I cannot build the riser to the optimal height.

Different communities have different requirements for minimum ceiling height for an inhabited space, and many times it is tied to a maximum amount of the floor area/ceiling area. Your code may read something like this:

"In habitable rooms, ceiling height not less than 7' over 50% of room area.
Remaining area 5' minimum. Minimum height under duct and beams not less than 6'-4'."

This one is based on the BOCA code I believe.
It is a little vague, and many areas have tons of amendments.

I definitely wouldn't count on a favorable inspection using the 5' minimum for 49% of a room... and that wouldn't be safe anyway.
That portion was intended more for the sloped ceilings of attic spaces and other areas where the ceiling slopes with the roof line.

If you go by the 6'-4" clearance, this means your 7'-6" basement gets a 12-13" max riser by default. Keep in mind that pad and carpet will add some height. 6'-4" is pretty low, you may want to experiment standing on a stepladder or with a temporary platform to see if you would be comfortable that close to the ceiling. You don't want to re-do a riser...

Many times this will not be the ideal riser height by the calculator, but safety must come first.
Consult an architect and/or your local building inspector before you push the envelope.

In these cases, compromise and creativity are required.
If your guests are constantly hitting their heads when they step up on the riser, or stand up from the seats, they will be seeing stars, not your properly laid out stadium seating theater.

Some ways to improve LOS in low ceiling applications:

1) Choose taller seats in the rear row(s)
Continental is one company that makes a "tall" chair to match a popular model that is like 5-6" higher than the matching regular height model that we would use in the front.
http://www.continentalseating.com/gable.html
This way the seated height is higher, but the riser height and standing headroom are still acceptable.

2) Make the front row the "money" seats, and choose non-reclining chairs for the riser that can be placed closer to the front row.
Irwin and a few others make nice non-recline chairs that are exact replicas of commercial theater chairs in the industrial upholstery or finer finishes. If you match the upholstery these chairs do not look out of place, and kids love them.

3) Raise the height of the screen a few more inches
If the rear rom are your money seats, you will want to LOS to be as close to perfect as possible. You don't want the front rows to be craning their necks up either, nobody wants a stiff neck after a movie. Be careful how much you modify this dimension.

Depending on ceiling height, basement theaters will get usually get a 5-8" step up riser or a 10-15" two step riser, and even with the creative planning for the seating and screen height, the LOS is sometimes slightly compromised.

IMO, this is still the appropriate way to plan.

BTW,
The building code requires that a step in a home is no greater than 8" per step, and the run (tread depth) is no shorter than 9".

Above 8", you have to install a step on each side and that eats floorspace and/or riser space. A 10-12" run on a tread height that is half the riser height is the rule for us, no higher than 16" of course, or a third step is req'd.
Also, 4 or more steps require a handrail in any area, and in some areas it is 3 or more steps.

DIY theater guys need to heed the building codes if you ever want to sell your homes down the road. Otherwise some of your theater budget for your new home will be spent making changes to the theater you are leaving before you can sell the house.

Wish I had this when I was building. Your recommended riser height is 8 7/16". I built mine 9" and the back row can easily see over the front. Thank you so much for doing this. It will save others a countless amount of time.

If you are going to do a riser shouldn't it be atleast a foot tall?

This may be obvious to most but FYI, Most building codes call for a maximum riser height of 8-1/4". So a 12" landing height should have a 6" step between the lower and upper level. ;)

By the way. Thanks for the AMAZING calculator. Everyone is so helpful here!

I actually ended up going with a 10" riser with a step all around it. It actually came out really nice...

You guys give me a headache! What am I missing?

My front screen wall is 10ft... I'm going to mount the screen so the top is at the 8ft mark... that seems to look the best when seated.

When I make my rear riser, I was just going to make it 7", which is the height that 4seating.com makes their risers?

Seems like this is being made more complicated than it needs too.???

quick question for you guys... having a too big of a riser bad? also what is the max ceiling basement height allowed? Because i'm going to be moving in a new house, and was wondering so i can get my floor plans done... here is a quick layout of the theater room...
20'x30'xH?' (WxLxH) room. The Pj will be mounted about 20-23ft back from the wall... and was thinking 2 rows of seating(5xrecliners each row), the first row 15-18ft back, Was also thinking about getting floor shakers too...
with all that in mind, what should the riser height be?(i also have a tall family, like everyone is above 6ft)
how high should be the ceiling?
how far from the ground should the screen be?
any suggestions and help would be much appreciated...
also if the basement wont work, i could always put it on the second floor, but would prefer it in the basement... thanks

Arty

As mentioned earlier in this thread, good sightlines are the result of many variables which include riser dimensions. I still believe in a good drawing (in scale) instead of mathematical formulas. When you draw your floor plan, expand it to show a section through the room. Here is a typical sightline drawing (http://www.dileo.biz/Sightline_drawing.htm) without dimensions. You may of course simplify - the idea is to show the basic geometry.

I have been trying to find some sort of formula to calculate the height of a single riser for approx. one month. Nice job, quick and easy answer to my question, Thanks, BG!!!!

anyone else getting "page cannot be displayed" errors for the riser calc link?

I just tried it and got the same message. You can always use the formulas. It takes a little longer, but gives the same answer!

Rob

anyone else getting "page cannot be displayed" errors for the riser calc link?

Sorry, I actually have this hosted through my dsl line right now so it isn't 100% reliable. Should be back up and running now.

Got to the page with no problem at all

thanks

geoffrey

Just found this thread, and am almost to the point of building my riser, thanks so much :)

Are there any standards for the optimal height for a viewer with a given screen height? ie SMPTE?

Thanks,

Mark

good info thanks

I can put the link to this on my yahoo storage space if you can send it to me. Can we get the fantastic link back up again?

Gary

Thanks for the riser calculator it worked like a charm!

I've been playing around with Jake's riser calculator (http://www.cinegi.com/cgi-bin/riser.cgi) and getting a some ideas about riser height. However, I'm having some trouble with some of the measurements -- I've placed an order for some home theater seating, but I don't actually have it yet (from which to take the measurements).

Does anyone have a set of Studio Collection (http://www.htauthority.com/usa/index_files/StudioCollection7563Zoom.htm) seating that could help me with some measurements? The numbers I'm missing are the "height of seated front row viewers top of head" and the "height of rear row viewers eyes". (I've found some dimensions (http://www.htauthority.com/usa/index_files/image1337.jpg) for the seating, but without knowing the height of the back, I can't really figure out those numbers.)

Oh no, link seems to be down. Time to plug the formula into Excel...

For those off-line, here's a spreadsheet calculator.

Toe-Knee

Oh no, link seems to be down. Time to plug the formula into Excel...

I got a new Router (3com 3030) so my connection *should* be much more reliable now.

Don't forget, everytime you open microsoft office:
a kitten dies/an angel loses it's wings/the animated paperclip steals some of your soul
er something like that....

-Jake

What I would like to do is make a new calculator, this will be much more complex and take some time, but here are my ideas:

this will require room height, width, length. It will make a recommendation for number of riser levels, but allow the user to select how many they actually want (IE room size will allow for 3 riser levels, which script recommends, but user only actually wants 2 in room...) it will have defaults for several items, but all of course are user changeable: 4' riser for standard theater seats, 5' for nonreclining chairs/sofa, 6' for recliners (In my experience these approximate numbers usually work pretty good).
It will then give recommendations for riser height/placement, screen placement and maximum size (limited by riser visibility, or SMPTE/THX viewing angle for closest row)
Any recommendations? Hopefully I can have this done in a week or two (don't have a lot of free time)

Has there been any progress on this?

In my opinion, you may want to put in the different chair companies and chair models available on the market, and start from there as another input along with room constraints, etc.. although, sometimes riser decisions involve more factors than just math. I wrote about this a couple of years ago in Home Theater Builder (Whatever happened to them??):

http://www.dileo.biz/Location_HTB_0203.pdf

Has there been any progress on this?

Sorry, this is far from the top of my todo list (down at the bottom with all the other projects that won't do anything for my retirement fund)

Maybe someday...

Just wanted to also thank you folks for this fine calculator...

Like I always try to do, before starting a thread on riser height, I figured I'd do a search to see if the topic had already been exhaustively covered and it obviously has...

Thanks again...

Just one comment - earlier in the thread someone is talking about risers, ceiling heights and code violations. this wouldn't be a problem if I make it a temporary riser, right? My basement is already carpeted, so I figured, just lay a riser on top (not nailed down), and carpet that as well. It should look ok, and can be moved/removed/disassembled at any time.

what is the link to the riser calculator

Just used this tool, I'm about to build my riser and was looking for the best hight. This made it simple.

Best part is tring different numbers......move the screen up and down a few inches and see the results.

Thanks for the work everyone.

This is a great tool but I'm unclear as to what the ideal height of the screen should be. Early on in this thread someone tossed out a number but is their an accepted percent of the screen that should fall below the eye level of someone sitting in the front row? Is there a similar tool for a screen height calculator available?
Thanks for your input.

David,

A good rule of thumb is that you eyeballs should be a 1/3 of the way up from the bottom of the screen. This is just a guide based on a comfortable angle to view a movie. Some people may like the screen a little higher and lean their seat back, but most people don't want the movie fully reclined.

I used the 1/3 rule, but in need to move my screen up another two inches some my riser would not have to be 16" tall.

J-dubb

J-Dubb
That was just the straight forward answer I was hoping to get. I think I will be using the Ekornes stressless chairs in the front row so I'll go check them out tomorrow with the 1/3 rule in mind. I just ran the riser calculator and discovered that my riser will have to be about 14 inches. That seems a little high given my ceiling is just a little over 8 feet. Maybe I'll grab those same couple of inches back on screen height to get the riser down to 10-12 inches. Thanks again.
David

Great calculator! How would you use this if you had 2 risers + floor level? Just do the floor and first riser and then use the numbers of the first riser to calculate the second riser?

Any chance that the calc page be ammended to suit metric users.

Feet and inches mean next to nothing to me as I work in SI units

Mick

Wouldn't the math be the same if you pretended that Inches = centimeters or any other units?

As much as I would like to advocate the US switch to metric, I have better things to do with my time right now. I would suggest getting a calculator that does the conversion for you (I use one on about a daily basis)

X: http://sourceforge.net/projects/x48
OSX: http://www.hpcalc.org/details.php?id=5829
WIN: http://www.hpcalc.org/details.php?id=3644

BTW
1ft = 12in
1in = 2.54cm

Is it just me or is the link not working anymore to get to the calculator?

Works for me!

would guys close, seal your riser or leave it open (in both cases of course carpeted) ?
and leave it empty or fill it with foam or glass whool ?

thanks

ok I got it working now....must have been on my end...hmmmmmm

ok I got it working now....must have been on my end...hmmmmmm


Maybe not on your end. My DSL service has been terrible for the last month or two, and the Qwest technical support half-a-world-away is less than helpful.
If you are having problems I would suggest trying later. I will keep after qwest for a fix.

This is really good! Thanks!

But how about a calculator for the third row ?

-Rajiv

PS: I did do a search for 'third' but nothing came up.

This is a great tool but I'm unclear as to what the ideal height of the screen should be. Early on in this thread someone tossed out a number but is their an accepted percent of the screen that should fall below the eye level of someone sitting in the front row? Is there a similar tool for a screen height calculator available?
Thanks for your input.


David,
Check this site for the ideal height of the screen and viewing angle (also has THX recommendations)

http://www.myhometheater.homestead.com/viewingdistancecalculator.html

-Rajiv

It's nice to know when you've spent time making something, that it's actually getting used. I was just noticing how much traffic the riser script gets, so I made a quick report. I was so suprised I thought I would post the results.

The log started from when I last rebuilt my server (Aug. 19, '05 -- so ~1 year of traffic).
riser.cgi
Total Page Views: 18157
Unique Visitors: 6964

Thanks!
-Jake

Thanks for the calculator, but what about the calc for a third row.

The new home we're thinking about will have the HT on the main floor, it will be 15x25x12. The first and second rows will each have 4 090 Berks while the 3rd row will have 2 090 Berks.

Is it right to assume the 2nd riser height should be the same as the 1st riser.

Thanks

Thanks for the calculator, but what about the calc for a third row.

The new home we're thinking about will have the HT on the main floor, it will be 15x25x12. The first and second rows will each have 4 090 Berks while the 3rd row will have 2 090 Berks.

Is it right to assume the 2nd riser height should be the same as the 1st riser.

Thanks

You should be able to use the same riser height/depth for additional rows.

If the third row will have different seats/measurements than the second, just use the calculator treating your second row as the first row, and your third row as the second row.

Hey guys just did my calculations and hit dead on 6". Great tool!

My question has to do with the fact that I will be having my subs sitting (depending on how wide I build my riser) either right beside or on top of the riser.... For bass considerations, should I close the riser off (a box) or keep it open?

My room tends to be a little bassy anyway, but not sure if the riser will create a bass trap and deaden it or elevate the perceived bass.

Any help would be greatly appreciated!

Thanks,

Steve

good job. :)

how do you make a riser with 2 levels?

Anyone use a riser as a subwoofer?

Nobody told me there was gonna be math,

First I marked the wall where the screen was going to go. Next I lined up two tall recliners (the back at about the size of an average adult) one behind the other facing the screen. Finally I laid an old bookcase on its front and put one of the recliners on it. I sat in the rear seat. I could see the bottom of the screen mark. 9"is the height I will build my riser.

Can anyone tell me a good height to put my screen at? I will have three rows of seat the first one being 10.5 from the screen and there are two 12" risers to the third row.

Any ideas. I have been playing with 2 to three feet from the first row floor
Thanks
Chris

Ok, I must be real dumb. I had someone install a screen for me that appears to be reasonably high enough. I plugged some numbers into the calculator and got this:

Floor to screen bottom: 32.25"
Height of 1st row: 41"
Height of 2nd row: 41" (both rows have the same type of chairs)
Screen to 1st: 13'
Screen to 2nd: 19'

then it gives me:
Minimum ri9ser height: 4"

Is that correct? I need to make a riser that is only 4" high? Is it just me, or does that sound ridiculous?

What am I not getting?

The measurement for the front row is the height of the top of the viewers head. The measurement for the second row is the height of the viewers eyes. If both rows have the same seats, the second row measurement should be somewhere around 5" less than the front row measurement. If 41" is the top of head measurement, you'll probably end up needing about a 9" riser.

Rob

Thanks. I missed that nuance.

What's the rule of thumb for a step? At what point is a step "too high" (i.e. you need an intermediary step before it). When I measure the steps in my house, it looks like they are between 6"-7" high.

Thanks.

I don't think there is a hard and fast rule. My home steps are 8" high. My riser ended up being about 18", and my 9" steps seem fine. There's no reason you couldn't do a 4 1/2" step if you wanted to. Whatever feels right to you.

Rob

Does the riser height calculation depend on the height of the person sitting on the chair?
My girlfriend is 4'10" tall. If I used her as the measurement would the riser need to be higher?
(Suppose she wanted to sit in the back row and have a clear view of the screen over someones head.) I'm having difficulty grasping the concept. If you use a tall person (lets say 6'5") then would you need a lower riser height?
Thanks.

The calculator assumes the same height person in both rows, with the same type of chair. The defaults are very close to my own measurements, at 5'9". You can adjust these as you see fit. If shorter people will be consistently in the front row, the riser can be made lower. If they will be in the back row, the riser will have to be higher. For example, if your girlfriend likes to sit in the back, and you have a lot of tall friends who will be sitting in front of her, use her seated eye height for the rear row measurement, and their top of head height for the front row measurement. This will result in a much higher riser, but will guarantee her a clear line of sight. Switching their positions around will result in a lower riser.

Rob

SUPER cool! Thanks a bunch.

What's the general consensus on offset seating? I will have 3 front, 2 rear... not really sure how to take this into account when using the calculator. Im pretty sure I will need less height on the riser than if I had a 3+3 seating configuration, without the offset. With 3+2, the rear viewers will get to see between the front viewer's heads.

Thoughts?

No one care to comment? I figure this is something that needed further discussion!

What's the general consensus on offset seating? I will have 3 front, 2 rear... not really sure how to take this into account when using the calculator. Im pretty sure I will need less height on the riser than if I had a 3+3 seating configuration, without the offset. With 3+2, the rear viewers will get to see between the front viewer's heads.

Thoughts?

I think there are a lot of variables that would be dependent on the type of seating you're using: couches, theater chairs, with or without arms, high or low backs. I think it's way too complicated for a simple calculator like this. Even if you get it all sorted out, what if the two people in front of you don't sit straight up in the middle of the seats, but both lean in towards the center? Unless you are really restricted with the riser height, I'd wouldn't count on seeing "through" the front row. Just my opinion.

Rob

What's the general consensus on offset seating? I will have 3 front, 2 rear... not really sure how to take this into account when using the calculator. Im pretty sure I will need less height on the riser than if I had a 3+3 seating configuration, without the offset. With 3+2, the rear viewers will get to see between the front viewer's heads.

Thoughts?
Unless your screen is narrow enough that it can fit between the two viewers' heads in front of you, they will be in the way regardless of seating configuration (3-3, or 4-3, etc). Their head will just be in the way at a different position along the bottom of the viewable image.

Is there any posted info on the average hight of someones head/eyes on different seating?

Figure the average person is 5'10" or 6'.

The reason I ask is im limited on ceiling hight, and I want to go with as big of a screen as i can, but i would like to know what my options are for seating.

Is there any posted info on the average hight of someones head/eyes on different seating?

I don't think so, but if somebody wants to do the research I would post/link to it right on the calculator. I guess we could also collect it right here if people want to post their own measurements (standing height, seating manufacturer/model, seated floor to eye height, seated floor to top of head height).

Personally I think you can stick with the default numbers and it will work out pretty well. I mean it may never be perfect, but at least in your own theater you can ask tall people to sit on the back row. Of course I'm not very sensitive to this problem, so I know this won't work for everybody.

Very handy program. Thanks for saving me a few "steps".

IPersonally I think you can stick with the default numbers and it will work out pretty well.

Please explain to me why the "default number" for front row head height is 42", while the back row head height default number is only 36". Does that calculation presume children or midgets in the back rows? It makes a huge difference in riser height if you switch to using the same head height for front and back rows.

IB

Because the back row number is actually eye height, since the image needs to clear the front row heads but only needs to reach the back row eyes.

Because the back row number is actually eye height, since while the image needs to clear the front row heads it only needs to reach the back row eyes.

Thanks. That makes sense.

IB

Anyone having trouble with the calculator - seems to be hanging up on calculation - tried IE, Firefox and Safari (from different computers, networks and firewalls).

db

Anyone having trouble with the calculator - seems to be hanging up on calculation - tried IE, Firefox and Safari (from different computers, networks and firewalls).

db

Seems to be working fine, but I'll take a more in-depth look at it tomorrow. The only thing I see in the error log are divide by zero errors (user input errors). I'll add some input verification and error handling so those can't happen anymore.

-Jake

Worked again for a few days and died. Sproadic (never had trouble in the past).

I've DLd the .xls file for now.

db

Great calculator, it confirmed my height idea of 12" :)

Worked again for a few days and died. Sproadic (never had trouble in the past).

I've DLd the .xls file for now.

db

I added the input validation today. please PM me with the values you are submitting if you have any problems in the future. Also, please note that the URL changed for the calculator. I don't think this could be causing any problems, but I will probably let the old domain expire next year.

-Jake

How would one calculate for a 3rd row? Just make another equal to the 2nd row?

quick question, should my front row look up a little and my second row be looking dead center of the screen(with full view of screen as well) is this correct??

Good question. I am actually at this point also so this question could not have come at a better time. The way I look at it is that my first row will be the "premium" everyday seat so I will have the eyeballs in the middle of the bottom 1/3 of the screen, then using the riser height calculator, determine what the riser height should be for the second row to clear the heads of the first row.

My first concern is that my riser may need to be 14", so I'll have to use 2x12 instead of 2x10 or 2x8.

Second concern is if the screen is placed a bit higher for the first row to be looking up slightly, what would be the limit before neck strain sets in. I will have recliners in the first row and real theater seats in the back row.

As mentioned earlier in this thread, good sightlines are the result of many variables which include riser dimensions. I still believe in a good drawing (in scale) instead of mathematical formulas. When you draw your floor plan, expand it to show a section through the room. Here is a typical sightline drawing (http://www.dileo.biz/Sightline_drawing.htm) without dimensions. You may of course simplify - the idea is to show the basic geometry.

You might want to change your web links. They lead to a sextoys site.

I really appreciated the perspectives regarding riser height. We have just started our process for a 13Wx25Lx7.5H HT.

We originally had a 10'Wx7'Lx6"H riser for the second row roughed in when I realized that it may not be high enough for people in our 4 w/loveseat Pallisers to clear the first row of 4 w/loveseat Pallisers. My 92 inch diagonal screen has to be about 35 inches from the floor.

After seeing all of the commentary on this thread as well as the calculator, I expanded the riser to 12" with a 22" wide, 6" front step. This also leaves ample room to be on the top part of the riser before seating down (about 22" as well). I am glad I started with a decent sized 7' footprint. My wife thought I was obsessing and being overly anal about the whole thing.

Once my contractor made the change, it was clearly the right move. I will not have any issues seeing the full screen from the second row. I also ended up with just under 6'8" height from the riser to the ceiling.

Thanks again!

Thanks. I missed that nuance.

What's the rule of thumb for a step? At what point is a step "too high" (i.e. you need an intermediary step before it). When I measure the steps in my house, it looks like they are between 6"-7" high.

Thanks.

Check your building codes (there is discussion on page 1 about this). Quick answer -- under 8" / step should be ok.

Great tool! I was guessing I needed 12" and when I measured and punched the numbers into the calculator, it came up 11 5/16. :)

Thanks a million!

Very cool program. Thanks for sharing.
RG

Just wanted to add my thanks to the rest. Used this calculator to determine my riser height and it worked beautifully to give me a riser height of 12". Showed a movie last night utilizing my new Berkline 099's...not a complaint out of anyone!

Just wanted to say thanks for the riser formula. Worked like a charm.

Here are some pictures of the riser.

http://i98.photobucket.com/albums/l264/Ryked/HT%20-%20Platform/DSCF5678.jpg http://i98.photobucket.com/albums/l264/Ryked/HT%20-%20Platform/DSCF5679.jpg

http://i98.photobucket.com/albums/l264/Ryked/HT%20-%20Platform/DSCF5681.jpg http://i98.photobucket.com/albums/l264/Ryked/HT%20-%20Platform/DSCF5682.jpg

http://i98.photobucket.com/albums/l264/Ryked/HT%20-%20Platform/DSCF5685.jpg

pretty good

Well, one way you can get around a riser is to create a bar behind your main seating area and have that seating be higher bar stools. Just looking for the more comfortable barstools that someone can sit in for the duration of a movie. Another advantage is that the rear seating area is then closer to the main seating area.

A friend went the opposite way and sunk his floor for the main seating area by about a foot into his basement (the extra height might have improved his audio response also). Then he built a table height bar directly behind the main sunken seating area [bar height is just below the average top of heads] and uses some very comfortable upholstered, high-back office chairs for bar seating. It brings six people close together in his 14 foot wide room.

What is the seat height for the average/representative reclining HT chair?

17ish" like normal chairs?