Fixing wall framing to floor slab

[MG David]

What are the most popular ways of fixing the wall framing to the floor slab?

At the moment I am planning just a storage shed so as to get things out of my garage workshop. The shed will have wooden walls on a cast in situ floor slab. Clearly the floor plate will need fixing to the slab. I am a little concerned about drilling for expansion bolts only 2 inches from the edge of the slab. Perhaps I should cast threaded bar or metal straps into the slab.

 

[larry4406]

New slab - cast in place threaded anchors or straps

Existing slab - cut nails (may be difficult depending on slab hardness), expansion bolts, or TapCons.

 

[Kevin54]

Drill holes and epoxy in threaded studs. This way when the nut is tightened it will not expand out in the concrete like an anchor is designed to do.

 

[uhcrandy]

Pick up a powder actuated nail gun. Its basically a nail gun that fires a hardend contrete nail, with a gunpower charge. They are under $50 and a good reason to have a new tool. If it needs to be a structural conection than the above conectors make more sense.

 

[Justanoldguy]

The gun more than likely will blow out the side of the concrete.
Very dangerous near concrete edges.
Drill and epoxy a rod is by far the safest.
Or in your case, put them in when you pour.
Put a bend in them so they don't pull straight out when you tighten them later.

 

[Nostraquedeo]

If it is an existing slab, you can drill holes with a masonry bit 5/16", then take a 16 penny framing nail and a three inch length of tie wire. Place the wire inside the hole, then drive the nail into the concrete along side the wire. This is a great solution. Not sure if it is code, but will hold just as tight as a Tapcon.

 

[little d]

^^^^^^^^^^^ +1

 

[Torque1st]

Try J-bolts, they are specifically designed for this application. They are embedded in the concrete when it is placed. Many codes call for them.

 

[Zeke]

If it is an existing slab, you can drill holes with a masonry bit 5/16", then take a 16 penny framing nail and a three inch length of tie wire. Place the wire inside the hole, then drive the nail into the concrete along side the wire. This is a great solution. Not sure if it is code, but will hold just as tight as a Tapcon.

How so? If the bottom plate is a 2 x 4 (1 1/2" thick), the 3 1/2 " box nail (or 3 1/4" sinker) will not be nearly 3" into the concrete.

I'd use a long attachment like a lag screw. I like Tapcons, but I haven't seen many 4 or more inches in length.

Epxoy'd all thread is how its done here in CA if there are no anchors placed in the wet mud. And the minimum depth is 16". Sometimes that is longer than the footing is deep. In that case we have to dig under the footing and place a square washer and nut on the extended threads.

But, we do live on earthquake faults.

Another thing you can do is use a offset clip that bolts down inside the plate and captures the plate as it goes over the top.

In any case, lightweight fasteners are not all that good. Just a good windstorm will upend a shed not tied down well.

 

[Stuart in MN]

Try J-bolts, they are specifically designed for this application. They are embedded in the concrete when it is placed. Many codes call for them.

I don't know what common practice is in the UK but this would be a typical construction technique in the US. One thing to consider - will the slab be high enough to keep the walls dry? When I built my garage I added a single course of concrete block around the perimeter so the walls are high and dry. In any case the bottom plate should be pressure treated material.

 

[Snap50]

Pick up a powder actuated nail gun. Its basically a nail gun that fires a hardend contrete nail, with a gunpower charge. They are under $50 and a good reason to have a new tool. If it needs to be a structural conection than the above conectors make more sense.

If it's old concrete, that's more than likely to just cause spalling.

 

[Snap50]

Use expansion bolts.....drill holes, tap exp bolts in, place a washer and nut and wrench tighted them. Simple.

 

[Torque1st]

They make coupling nuts and threaded rod in case you want to place a course of block on the slab.

The nuts on the bolts should be just snugged up.