Should I drill into my basement floor?

So, I'm in the home stretch in my home theater build. I'm planning on having three rows of proper theater seats, installed on a riser. They mount with two bolts/screws per side. The front row is where I'm unsure. I could drill into the concrete floor and install anchors of some sort, or I could drill and set upturned bolts in the concrete, making studs sticking out. Or, I could build a short platform to bolt the seats to.
I like the idea of the small platform because it doesn't involve drilling into the concrete floor, but the height would be tricky to avoid a trip hazard (can't go high enough to make it a natural step or the rear row will be too high). But the platform would have to be thicker than the flooring, that's why I'm afraid it'd be a trip hazard.
So, should I just drill in the concrete floor? Is there a draw back to that? Could I introduce water into the basement or cause other damage?
I have no idea how thick the floor is or anything. The house was built in the early 50s.

What do you guys/girls think?

3 of these instead.

If you don't have any obvious things in the concrete floor (radiant floor heating?) - you should be fine. Use the proper fasteners for concrete.

In reply to logdog:

Three of those would make it look like a constipated triceratops passed through his basement 27 million years ago

captdownshift wrote: In reply to logdog: Three of those would make it look like a constipated triceratops passed through his basement 27 million years ago

Leave it to Logdog to leave a comment like that. Ironically, most of his 'jokes' are turds, much like those giant triceretop turds.

I wouldn't hesitate to drill the floor. I'd be more tempted to epoxy in a stud than use regular anchors. Most anchors are designed to go in once and never move again. I can envision needing to pull seats for replacement/repair/removal in the future.
As a bonus an epoxied in bolt should be water tight.

I'd drill the floor. You probably won't go all the way through but if you do a squirt of sealant when putting the lag bolt in will seal it up. Expanding lead anchor and 2" lag bolt will be more than enough to secure seats and not be a toe hazard like exposed studs could be.

mazdeuce wrote: I wouldn't hesitate to drill the floor. I'd be more tempted to epoxy in a stud than use regular anchors. Most anchors are designed to go in once and never move again. I can envision needing to pull seats for replacement/repair/removal in the future. As a bonus an epoxied in bolt should be water tight.

I would hate to see the stud sticking up as a tripping hazard. When the seats got removed, you'd never cut a stud off low enough to be flush. And if you're dependent upon not having cracks in the floor to prevent water infiltration, you probably shouldn't be finishing the basement anyway.

Put a female expansion anchor in the floor and set it a little below flush. Then if the seats are ever removed permanently, you can backfill it with a little epoxy grout.

What about a 1/2" of good plywood attached to the upper seats' platform. Have it covered with some very dense foam and heavy fabric. Drill holes for the seats and have t-nuts on the bottom. You might have to recess them a bit.

You could ever chamfer the edge to lessen the chances to stub toes or trip.

Drill it and use Red Head concrete anchor thingies.

Duke wrote: I would hate to see the stud sticking up as a tripping hazard. When the seats got removed, you'd never cut a stud off low enough to be flush.

Grinder with a zip cut blade. Do it all the time.

Where's your water table? I'm at the top of a hill but the water isn't too far below my basement floor. My sump always has water in it.

Build a box and never worry about your concrete floor.

I wouldn't have hesitated to drill into a concrete floor. Concrete is not a waterproof membrane. If there's water present under your concrete it would already be coming through.

Drill it and use anchor inserts with bolts from above. Setting a leave in place stud is asking for trouble. (stubbed toes, damaged threads, whatever.)

for what it is worth, we use anchors in our one theatre at the Borgata. 3 chairs on either side of the stage are removable so we can fit stairs for those performers that want to walk down into the audience from the stage. Except for an instance were somebody tried to use the wrong bolts to put them back in, they have worked like a charm for the last 12 years

Hilti Titen screws work great also. No stud or anchor, just a hole. They come back out just fine.

java230 wrote: Hilti Titen screws work great also. No stud or anchor, just a hole. They come back out just fine.

That's cool. Me likes. Not much thread depth, seems like the diameter of the hole should be pretty close huh? I like it though.

In reply to DrBoost:

They work really well. Same holding power as wedge anchors. And yes they tell you exactly what size hole is needed. And its often a weird one.

EDIT just looked. the 3/8" ones i have take a 3/8" hole. And they are Simpson not Hilti (although I think Hilti makes them too)

java230 wrote: In reply to DrBoost: They work really well. Same holding power as wedge anchors. And yes they tell you exactly what size hole is needed. And its often a weird one. EDIT just looked. the 3/8" ones i have take a 3/8" hole. And they are Simpson not Hilti (although I think Hilti makes them too)

Are these at Home Depot, or should I be looking online?

Zomby Woof wrote:

Duke wrote: I would hate to see the stud sticking up as a tripping hazard. When the seats got removed, you'd never cut a stud off low enough to be flush.

Grinder with a zip cut blade. Do it all the time.

Yeah, I always drill mine a little deeper than needed. When I cut it off I can then tap what's left lower than the slab and fill the hole with hydraulic cement.

In reply to DrBoost:

Appears my local HD has them. I go through a different distributor since I buy them with my hardware packages usually.

Zomby Woof wrote:

Duke wrote: I would hate to see the stud sticking up as a tripping hazard. When the seats got removed, you'd never cut a stud off low enough to be flush.

Grinder with a zip cut blade. Do it all the time.

Drill the hole deeper than the stud is long. When you are done, just hammer it into the floor. It's done here at work all the time.

Killed a canoe, nothing new to see here. Carry on.