I have a job where we have a half wall over a concrete slab and I’m trying to find some hardware to make it as rigid as possible.
I looked at Simpson’s site but couldn’t find anything that fit the bill. I would imagine that someone has a bracket that you could fasten to the slab with wedge anchors or epoxy and all-thread and bolt that off to your studs to give lateral stability. Anyone have a solution?
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Replies
You might take a look at the vinyl post to concrete anchors from a vinyl column/rail company. Maybe it could be purchased separately.
But, I'm thinking I saw a bracket somewhere that incorporated a steel plate and brace with the threaded rod.
I had fairly decent success with a stair parts company (maybe smith) base bracket that screwed to the bottom of the post and then you screwed that to the concrete. I added that to an epoxied into concrete rod that went halfway up the post, imbedded in the post with epoxy as well.
A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
Quittin' Time
I just last week used some of those vinyl post bases for a very similar situation and it worked great. I discarded most of the pieces, but the important part was a very thick (1/4 at least) steel plate that was drilled all four corners and had a center holes for attaching the post. About 10 bucks a piece at HD.
PaulB
I've done this many times with excellent results and am sold on the following method.
Start by framing the wall with double plates on the bottom, for something with meat to bolt through. Drill 3/4" holes in the concrete through the double bottom plate for 5/8" threaded rod, epoxy rods in place with simpsons expoxy made for such things and use construction adhesive between conrete and wood. Rods every 4' work well. That has securly anchored your bottom plate, but your wall will still be a limp noodle if you don't go one step further.
Next, sheet both sides of your wall with 3/8" or 7/16" osb, nailing as if it were a sheer pannel. This locks the secure bottom plates to the studs for a very steady wall.
If sheeting both sides of the wall makes it too wide for some reason simply rip the studs down the width of the sheeting.
If wiring needs to be run in the wall it's a very simple thing to drill the studs for the wire and simply run a length of romex for the electritian to use later when he hooks everything up. He will appreciate not having to mess with running wiring in the sheeted wall, although it is easily done with a 5" hole saw, making a hole centered at each studd. The 5" diameter hole allows enough room to pass the wire from stud to stud. If you don't have any romex handy, simply drill the holes in the studs, aligned as straight as possible, and put a wire or rope through the holes before sheeting for the electrical to use to pull a wire when he wires outlets/switches.
Other carpenters who have seen how firm these half walls are are impressed and usually try the technique. Almost always they try to omit sheeting on one side (about 1/3 as effective), or use a single bottom plate (2/3 as effective) or they don't nail the sheeting as they should (1/2 as effective) or something else and their walls suck because they tried to cut corners.
Gluing the sheeting with construction adhesive helps, but it's usually easier to simply use more nails or staples.
Good luck,
Don
Questions: are the threaded rods merely to hold the bottom plates down tight? could one also use a 6" or 8" simpson quick bolt? Also do you stagger your bolts as well? I'd guess that you would as opossed to center. and really all you need is every 4' ? cool..I'd have thought maybe a little closer than that.
It sounds like what keeps the wall from moving side to side is the plywood holding the stud wall to the 3" of bottom plate. take away one side of ply and the wall will have a tendancy to still lean back on the one side that has ply. take away one plate and you've got less meat for the plywood to hold onto along with less rigidity. every thing you describe makes alot of sense. nice design.
Edited 11/5/2005 6:42 pm ET by alrightythen
Calvin,I like your suggestion. I should have mentioned before that the concrete slab is already in place (basement finish job). I would like to avoid cutting concrete and I think the post bases are just the ticket.
Jon Blakemore RappahannockINC.com Fredericksburg, VA
I tell you what Jon, could you come back here and lay out the parts, the technique and the outcome. This question comes up just often enough to have a tested answer.
And here's another one I should have thought of first off.
I've done a number of bars and their stool hardware is simple, easy to fabricate and I imagine in quick time, easy to order. Many have bases that bolt down, holding the stool. Others have a long rod welded to a plate (or bolted) that you torque down. Firm anchorage with wedge anchors. If you have gone to any bars, you know what I mean.
Call a bar stool company.A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
Quittin' Time
I like Calvin's suggestion.
I have in the past used a coffee can to void out the spot where the end of the wall is to go during the initial pour. This will leave you with a 6" hole in the floor, Large enough for some margin of error. Then you just put a green 4x4 at the end of the wall and grout it into the floor. Perhaps you can just cut out a square of the floor and use this method.
I'll vouch for IdahoDon's method... use a 4x4 PT for the bottom plate, epoxy it to the floor and use all-thread epoxied into the slab as mechanical fastening, with bearing plates instead of the usual washers. Glue the plywood to both sides of the framing and use 10d nails spaced fairly closely.
All the suggestions are good but the simplest hasn't been mentioned.
Just do a good job gluing and cut nailing and then make sure your studs are locked to the bottom plate.
All of this depends on the condition of the concrete and the expected loads that might be applied later.
Being generous with the glue when the board is applied is helpful too. Anything that locks the studs to the floor adds to the overall strength.
I'm sure you already knew all this and was looking for something a bit more advanced, but I'm just saying: don't underestimate the new construction glues in light duty applications.
blue
So, Similar situation, however the half wall is being built on a slab floor with radiant heating. Does anyone have any suggestions for a means of fastening this wall without any drilling into the slab?
Any further input on constructing a half wall on slab floor with radiant pex tubing? I planned for the 7/16" osb on both sides creating a shear wall but anchored the base plate with Tapcon screws imbedded in the heated slab only 1" to avoid hitting the PEX tube. Suggestions?
I'd echo the points made about modern construction adhesives. Just used some gorilla glue (ultimate?) and was pleased with the grab and eventual hold. I'd back the tapcons out and glue it up.
Set the radiant heat to high and use an infra red camera or a laser (point and shoot) thermometer to find the radiant loops and then f=drill anchorage to avoid said loops. Embeding 1-inch into the slab is insufficient.