Do I need to reinforce the floor?

[Gripenfelter]

It's an office type tile ceiling. Very easy to expose the joists.

I'll look into more joists thanks.

[Myka]

You're welcome.

You have space between the joists and the dropped ceiling? I'm just wondering if you have space to hide the beam(s).

I don't think 2x4's are going to be enough, and I don't think you need to add another joist (that's a real pain in @$$ to do). You want to transfer some of the weight from the 2 loaded joists onto other joists (whether you are using jack posts or a beam or WHY). If you use hangers to mount a small steel beam(s) perpendicular to the joists and attach them to neighbouring joists you can transfer the weight by preventing flex. Need good hangers and good hanger nails. i bet you would only need 4" steel beams.

[sphelps]

If access isn't an issue you could just bulkhead in the two supporting joists by adding layers of plywood to each side of the two joists. Add 3-4 layers each side, glue and screw and stagger the seams to span the 15 foot length. Just make sure the ends are properly supported on the concrete wall.

With the floor properly supported, you could build a stand that distributes the weight properly and if you add a layer of high density foam between the floor and the stand you shouldn't break any tiles. Grout lines might crack but that's easy fix, plus given it's marble or stone you probably wouldn't notice anyway.

[Gripenfelter]

Originally Posted by Myka

You're welcome.

You have space between the joists and the dropped ceiling? I'm just wondering if you have space to hide the beam(s).

I don't think 2x4's are going to be enough, and I don't think you need to add another joist (that's a real pain in @$$ to do). You want to transfer some of the weight from the 2 loaded joists onto other joists (whether you are using jack posts or a beam or WHY). If you use hangers to mount a small steel beam(s) perpendicular to the joists and attach them to neighbouring joists you can transfer the weight by preventing flex. Need good hangers and good hanger nails. i bet you would only need 4" steel beams.

Where would I get steel beams from? Home Depot? Rona? McDiarmid Lumber?

Originally Posted by sphelps

If access isn't an issue you could just bulkhead in the two supporting joists by adding layers of plywood to each side of the two joists. Add 3-4 layers each side, glue and screw and stagger the seams to span the 15 foot length. Just make sure the ends are properly supported on the concrete wall.

With the floor properly supported, you could build a stand that distributes the weight properly and if you add a layer of high density foam between the floor and the stand you shouldn't break any tiles. Grout lines might crack but that's easy fix, plus given it's marble or stone you probably wouldn't notice anyway.

Grout is epoxy so it stays flexible.

Not sure quite what you mean to do with the plywood.

[sphelps]

Originally Posted by Gripenfelter

Where would I get steel beams from? Home Depot? Rona? McDiarmid Lumber?



Grout is epoxy so it stays flexible.

Not sure quite what you mean to do with the plywood.

You can get steel I-beams from Varsteel or some kind of steel supplier in the area.

This is what I mean by creating the plywood bulkhead

Start with joist


Add plywood layer to cover entire span


Repeat staggering seams


Repeat again staggering seams and do other side.


You're simply increasing the strength of the beams (joists). By adding 3-4 layers each side on both supporting joists your floor will be strong enough to support the load without deflection.

[Gripenfelter]

Originally Posted by sphelps

You can get steel I-beams from Varsteel or some kind of steel supplier in the area.

This is what I mean by creating the plywood bulkhead

Start with joist


Add plywood layer to cover entire span


Repeat staggering seams


Repeat again staggering seams and do other side.


You're simply increasing the strength of the beams (joists). By adding 3-4 layers each side on both supporting joists your floor will be strong enough to support the load without deflection.

AWESOME IDEA!! I like it!!