[Kensmith48]

I've searched this forum and found plenty of info on building a riser. I only have one question--How to connect it to the floor if it's not up against the side walls. I'll be putting down a Delta FL floor with USB. Do I lay this under the riser or just put the riser on bare concrete?

 

[mn_hokie]

It's up to you. You want to have some kind of moisture. barrier between the riser and the concrete. The Delta floor serves this purpose so you can drop the riser right on top of it. That's how I did mine. The other option would be to use pressure treated wood for the frame of your riser. If you went this route, you could run the Delta flooring up to the riser and stop it there.

 

[Kensmith48]

Maybe the way I should have put it is how do you anchor the riser so it doesn't move. I know it has some weight to it but doesn't it have to be nailed, glued, or something? It seems that if it's not up against the back wall it could flip over.

 

[91BlckGT]

It would take a fairly significant event to flip a riser.


The last one I built (in my previous theater) was 7' wide, and 5' long x 12" high. It weighed a ton, and had a very low center of gravity. It was assbled out of standard 2x4's, 4x4 at the ends, and just plain old plywood covered with speaker carpet.


It sat on my carpet, so it didn't scoot, heck, I could barely lift it!


If you're paranoid about it moving, just make a 2'x2' center cavity in it, put a 3/4" plywood bottom on it, and fill it with sand. 200-300lbs of sand in a 2'x2'x12" space isn't going anywhere.

 

[mn_hokie]



Quote:
Originally Posted by Kensmith48 /forum/post/15513315


Maybe the way I should have put it is how do you anchor the riser so it doesn't move. I know it has some weight to it but doesn't it have to be nailed, glued, or something? It seems that if it's not up against the back wall it could flip over.

Assuming your riser is 6 feet deep or so, I'm guessing you would need hundreds of pounds in one spot to even get it to tip. Sit on the end of your couch and have 3 people sit on your lap. The couch still won't flip.


The weight of the riser, plywood decking, seating, and then people in the seats is more than enough to keep it from going anywhere.

 

[Kensmith48]

I didn't necessarily mean it would actually flip but maybe move around if not anchored down. People are getting bigger so I thought I'd check. Thanks for the answers.

 

[md1953]

I was confident that the riser wouldn't move, but to be sure I added four cleats between joists that were glued and nailed to the concrete. Not going anywhere now.