CMU Curb wall on slab - Questions

[Patman]

We've just had a slab poured for a detached garage, and are planning on laying a single course of block for the curb wall. I had a few questions on what do do after laying the block:

1. For the cells with anchors, is filling with mortar or cement the better practice?
2. Do I need to fill every cell after it's laid? If so, does it need to be with concrete, or mortar mix? If not, do the empty cells become a detriment to weatherproofing and insulation?
3. Do I need to apply any sort of coating to the exterior to weatherproof the block? The course is above grade, we're currently 50/50 on whether we'll cover it with siding or leave it bare.

Thanks for the help!

 

[rixtrix1]

When I had my attached carport enclosed, all the cells got filled with 10k/psi grout( the block . layers usually did tilt up structures and used what they had and normally use. No need for waterproofing with that they said, but when I did the floor, I sealed the "curb" too.

 

[KenC]

IMO, if the blocks will not be below grade, nothing is really required in the cells. For tiedowns, I'd much prefer drilling the slab, through the cell, and using an epoxy to bond it into the hole. The bond between CMUs and the slab is not very strong at all in many cases. Sika makes a good one that can be used with a regular caulking gun.

A strong wind push on the wall/roof could break that bond. But, I live in tornado alley do wind load on the walls is a real concern as I've seen it happen. Wall falls over blocks laying near it, disconnected from the slab.

If the blocks are below grade, even a little from landscaping, they will absorb water, even the mortar line at the bottom will seep if water stands against them.
I'd recommend a waterproofer on the outside if that's the case.

 

[NUTTSGT]

I like filling all of them. If you don't want to, I would at least do the anchor blocks and a few more. For me, that would be the corner blocks and a couple on each side, along with the blocks at the opening.

Any block I filled would also have a piece of rebar drilled and pinned into the slab.

I have no idea how big your garage is but core filling one course and a few pieces of rebar is cheap in the grand scheme of things.... and it's not like you can really go back and do it (easily) after the wall is built.

 

[Firebrick43]

I have no idea how big your garage is but core filling one course and a few pieces of rebar is cheap in the grand scheme of things.... and it's not like you can really go back and do it (easily) after the wall is built.

You can, surface bonded cement. The fiberglass reinforcement in it makes for a strong wall. Or if you want it to be bullet proof, surface bonded cement with a few layers of metal lathe pushed into it

 

[Rusted Nut]

How are the blocks attached to the slab? Rebar? How are anchor loads passed through to the slab? Answers to these questions will determine answers to your original questions.

 

[reader2580]

You can, surface bonded cement. The fiberglass reinforcement in it makes for a strong wall. Or if you want it to be bullet proof, surface bonded cement with a few layers of metal lathe pushed into it

The OP is only doing a single course of CMU so I am not sure that will help.

The contractor who did my slab installed rebar sticking out of the slab for the CMU.

 

[OccupantRJ]

I would use block sealer on the outside. Water can penetrate bare block and puddle on the floor. I had to seal my block stem wall to control issues. A ladder style reinforcement wire can be used in the mortar bond to help tie things together. Around here on residential jobs you might get the cells filled with mortar, but not often concrete. I anchored into the concrete floor through the cells every 4 feet bolting the sole plate down, then continued using a coupling nut and threaded rod all the way through the top plate, with square washer plates and more nuts. Hurricane country here. I am not a contractor or brickmason, but I do sleep with his sister every night.

 

[firebirdparts]

I'm with ken, you should not anchor to a single row of CMU's. That's not going to hold the building down in an emergency. After they dry really well the CMU's will come loose from the floor anyway.