Fastening Into Concrete?

[911pcars]

While a hammer drill may do it, a rotary hammer drill will cut through concrete like butter. Can rent.

Your local building code may have more specs on minimum anchors for earthquake holddowns.

Sherwood

[jyl]

This is for building out a basement. Fastening the bottom plate of interior wood framed walls to the concrete slab. Seems like a light load to me, unless I'm missing something?

[trekkor]

Use a 3/8" Red Head in every other stud bay.

Stand up your wall, drill through your sill plate and into the concrete with a hammer drill.
Place a washer over the Red Head and thread on the nut.

Pound it into the hole and tighten. You'll never look back.


KT

[look 171]

Get yourself a Ramset and shoot it in every 6'. I don't know about 6' up in OR. If you really want it to stay, rent a roto hammer and install 1/2" Red head anchor. Sorry, Trekkor, if you are going through all that work why not go a bit bigger. Pressure treated lumber for plates.

Jeff

[trekkor]

Either are fine.
It's not a load bearing or structural wall, plus I assume it will be tied into the ceiling, too.


KT

[sc_rufctr]

Are these the same as Readheads?

[MotoSook]

Basement wall=non load bearing & no tension from wind ; no need to to go crazy. You could even just glue the plate. Buy putting 3 smaller bolts on each wall would be easy. For an old basement like this, I'd epoxy in after drill...concrete might not have as much tensional stretch as today's mix...so better to spread the load out along the hole.

And you don't need to go deep! Just 2-3 inches into the concrete will do. I wouldn't want to go through the concrete in this case. You are just trying to prevent the base plate from moving along the flow, not lifting. 2 inches with say 3/8" bolt will prevent this.

[drcoastline]

I would still go with the Tap Cons. Strong yet easily removed for repositioning. Most other concrete fasteners will either damage the concrete or leave hardware behind that may be a problem in the future. The fastest and easiest way to secure the plate is to shoot a fastener in but, once you do you are looking at a lot of work to remove it if you end up being a 1/4" out of square. You also run the risk of the fastener not holding or blowing the concrete apart. It is not un-common to have sections of concrete cure improperly and be brittle.

Tap Cons are the ticket for your project. They take a little longer to install than shooting but if you nee to reposition just one section of wall you will be glad you did. For a partition wall a 1/4" or 3/8" shaft every 18"-24" should be sufficient.

[cbush]

I recently had to frame out a reinforced concrete garage- so had to make a lot of holes to attach the 2X4s and 2X6s.

I ended up using a large Milwalkee Hammer Drill to drill the holes, and Tapcon's as fastners. I tried using a non-hammer drill and got nowhere. I used a total of 10 drill bits for this rather large project as they do get dull fairly quickly.

I tried the gun actuated fastners, but they just bent after penetrating the concrete about 1/2 inch, and knocked out big chunks of concrete.

I didn't use some of the other fastners because I would have had to drill larger holes, and also had trouble lining up the multiple holes in the wood with the fastners.

As most folks implied, it kind of depends on what the project is. For my framing, Tapcon's worked great.

[javadog]

You don't need much for your application. Most of the replies are overkill.

Old carpenter trick: drill a hole in the concrete, through the sill plate and nail it down with 2 sixteen penny nails driven at the same time.

Or, just pre-drill a hole and use a concrete nail, Tap-con, etc. 100 year old concrete is hard and likely of questionable quality/consistency.

And, yes, you'll want to tie the top of the wall to the first floor framing.

JR

[gr8fl4porsche]

Just finished this project.

I used a bead of adhesive and 1/4" tapcons every 2' or so. Plenty strong.

I like to use metal track and pressure treated to eliminate rot in old basements. Even though the floor appears dry, you have constant moisture being drawn thru the slab by the HVAC system.

[billybek]

I drill through the bottom plate and into the slab with the Hilti drill.
Hilti makes these nifty inserts. Hilti Online - HPS
Just buy them long enough to go through the bottom plate 2x4 and into the slab.
These a great and quick to install.

[A930Rocket]

I'll revise my post now knowing it's an interior wall that's non-loadbearing. Tapcons or even cut nails will work. You're just trying to prevent shifting, not uplift.

As mentioned, treated wood where ever it touches concrete or masonary product.

[jyl]

Thanks!

I'm sorry if I wasn't clear on how light-duty the application was.

I did appreciate learning about the range of fastening methods, though - there is a carport project for later that will need the stronger methods that you guys also pointed me to.

[Zeke]

Originally Posted by jyl

This is for building out a basement. Fastening the bottom plate of interior wood framed walls to the concrete slab. Seems like a light load to me, unless I'm missing something?

That's light construction. Use anything that works. If you have a hammer drill, there are several options listed above.

For those reading this that may have another situation, let me make some notes:

Powder driven anchors don't work well near the edge of a slab or near an expansion joint. Neither do some some expanding fasteners.

Tapcons are expensive when driven through a 2x or 3x member as 1 1/2 to 2" are still in the wood. Long ones cost more than short ones.

Walls in compression only need enough fastening down to keep the wall in place; some walls need to be tied down better if there is a potential lift factor from wind. In some cases all you need is a wood dowel in a hole and a deck screw.

New, green concrete needs to be addressed differently than old. It has much less tensile strength for the use of driven and/or expanding type of fasteners.

Any anchoring device that is bonded or expands as it is driven into a bore has to go into a clean bore that has been blown out with compressed air or vacuumed with a small tube.

Always know the depth of the concrete so that the fastener can be placed at the optimum depth.

[RWebb]

John - you have Earthquake specs to meet up there, don't you?

We don't but when I dropped the downstairs interior walls last year, I added all sort of ties using epoxied bolts in the stem wall (as well as some other stuff)...

[Superman]

Depends on size. I attached framing to vertical concrete walls using a hammer drill, proper bits and special fasteners I simply installed with a hammer. For other applications, you might need to drill a bigger hole and epoxy some studs in.

[john70t]

Originally Posted by A930Rocket

As mentioned, treated wood where ever it touches concrete or masonary product.

Good catch. I think there is a base gasket(rubber or other) used to prevent wicking too.

Floors are rarely arrow-straight, and you could probably shim or shave off sections of the sill to help prevent future drywall movement.

The crowns of the studs are supposed to go on one side too(out I believe).

The strongest walls will have 1x4/6/8 purlined on both sides to x-brace them. It's a lot of work though.

[look 171]

Earthquake specs? Its an interior wall with no weight on it. put a couple of pins in and be done with it.

[jyl]

Interesting point - before I start covering up basement concrete walls, I need to think about any needed e-quake retrofitting. I'll start a thread on that.