Building A Strong Half Wall - Avoiding the WOBBLE!

Eliminating Half Wall Wobble!
FULL ARTICLE HERE:
www.aconcordca...
We typically see half walls at stair openings, replacing railings and balusters, as well as in bathrooms. In remodeling we use half walls with glass, a lot more in showers, to allow in more light.
Whether you call it a half wall, knee wall or Pony wall the issue is the same. They tend to be wobbly and cause client complaints. No one likes a wobbly wall, cracked plaster, or cracked shower tile that results from wall movement.
What is the best way to reinforce a half wall?
Reinforcing a half wall can be accomplished easily if the floor joists run perpendicular to the half wall. In this instance, simply run a stud or two down into the joist bay and attach it to the floor framing.
This method requires that the subfloor is open from the top or the ceiling is open from below.
How May Wall Studs Should You Attach?
You can do this on every joist, or just a few. Attach each 2x4 stud to the floor joist, or to blocking between joists, with construction adhesive and 3” structural screws.
If the floor joist is running parallel to your half wall, and the wall lines up with the floor joist, you can attach ½ or ¾” plywood the half wall and run the plywood down into the joist bay and attach it to the joist.
Need More support? Add Blocking On Either Side of Stud
For additional lateral support, adding 2x solid-blocking, onto the floor joist, on either side of the 2x4 wall stud will add more stiffness, and support to the structural screws. [This is a common method in reinforcing 4x4 posts in deck framing.]
Add Blocking Between Joists
Additionally, if the joists do not run in your favor you can add 2x blocking to better position the 2x4 stud support you need. Use 2x framing and joist hangers to ensure a solid blocking connection. Sometimes installing the joist hangers “upside down,” gives you better resistance to pulling.
Using Threaded Rod to Stiffen the Half Wall
The threaded rod method works great when reinforcing a half wall, but is hard to do and super time consuming. It requires using 1/2″ to 5/8″ threaded rod from the top wall plate down to blocking in the structural floor below. The use of upside down joist hangers is recommended to add tensioning strength to the blocking. You can read more about this method here.

[@ecospider5]

This was great. A view of the final wall would have been nice for those of us that don’t build every day. To see the relationship between what you showed and the final walk.

[@TheMixmastamike1000]

this video is great! I would love to see a deeper dive on the blocking mounted knee wall studs and other work-arounds or tips when things are non-standard.

[@wildgoose6596]

A simple solution to a common problem. A wobbly wall that is being tiled is a real problem, so that is a handy tip!

[@adampetten1009]

I wanna see more of these. This is gold for DIY

[@ConcordCarpenter]

Adam Petten thx

[@14mattomatto]

I agree. Great info Rob

[@carpenterdom1639]

DIY it up! I call that job security for me lol

[@ConcordCarpenter]

Felonious Fishing huh?

[@rickrudd]

GOLD JERRY, GOLD!

[@roverron7509]

We used to use a cheap framing square and sandwich it between two studs bolt it to the floor joist, worked quite nicely.

[@georgemckenzie2525]

As a stair builder I have adapted the 3/4 threaded rod technique from box newel systems into my half wall construction.

[@ConcordCarpenter]

threaded rod is ROCK SOLID

[@adde32332]

@@ConcordCarpenter I used the threaded rod technique, but not sure if I'm wrenching down the nut hard enough, because the wall still wobbles. How much are you torqueing it down by? I haven't put any sheathing on yet, which I'm sure will help. Thank you!

[@JuanMartinez-lp1bd]

I have been watching your videos for years. I am now ready to build my house. Thank you.

[@embatbr]

It has passed 4 years now. Have you built it?

[@Indianarailproductions]

Have you succeeded? I hope so!

[@Soup-man]

Keeping this in mind for an Eagle Scout project. Thanks for the advice.

[@kevinm8865]

Cool; I will def keep this in mind for future. Too late for me now. My half-wall runs about 10-15 feet and it wobbles. It's subtle but it's there. With more age it will prob be annoying and very noticeable. Thanks for sharing!

[@Roaring.On.Carnivore.]

Got it thank you 👊🏼👊🏼. So simple when you know how it's done

[@slivers4007]

Or get yourself a Kreg Jig HD and run long 1/4" GRK screws through the bottom of the "half wall studs" which in-turn goes threw the bottom plate into the joists or blocking below. Run one screw from each side of the stud. May have to add a few studs to match up with whats below and the layout may be off a bit but it is bomb proof!

[@ConcordCarpenter]

Mark V sounds good

[@CarolinaNaturalPools]

After seeing this video, we tried it on a remodel and it worked great!

[@dennisisenhour7399]

Best construction tip on KZbin

[@Atheyst]

Fantastic, a problem I've had multiple times but never thought there was a better wau

[@kizzjd9578]

I've done the threaded rod method before. It's very time consuming and hard to do with limited room in someones house. I found the easiest way is rip down your framing 5mm and sheet one side with 5mm bracing ply. Nail it as you would a bracing wall and once its all sheeted, it's rock solid. Make sure all studs are screwed rather than nailed.

[@sturdyvw]

Beat me to this comment lol

[@Relaxokay359]

That's good thinking. I'm going to do it this way. Thanks so much

[@Ty_N_KC]

Well I'll be damned..... a good Carpenter doing a good video. Subscribed!

[@mattchibi]

He's been coming out with videos for probably over a decade now ;) Rob Robillard folks

[@dennismadigan2023]

Thanks. I am about to build a half wall and I was wondering how to go about it. Now I know. Thanks again.

[@andrewalaska]

Strong walls when you can't get into the floor, as long as it's

[@TheZambie1]

I have a half wall on top and running with an engineered open web floor truss. My plan is to add steel. Simple. But I need to get in the habit of using construction adhesives more, too.

[@tedbaxter5234]

1st time viewer, I really enjoyed this video. Thank you!

[@lukehunter3902]

what if it's a concrete slab Rob???

[@lukehunter3902]

PS I love the video this seems like such a killer method!

[@ConcordCarpenter]

luke hunter steel braces or threaded rod or 5/8 x 8 bolt epoxied in and a Simpson HDU16 on the stud

[@gillgetter3004]

Heavy drive in anchors between each stud and lots of adhesive. Large flat washers on bolts

[@mansardmanor3869]

Best method, not easy method. Jack Hammer a round hole, make concrete footing for metal poles, round or flat. Use metal nails with cap gun to attach wood framing. Don't saw cut nice square holes then breakout concrete, that will seperate the finished edges, keep edges raw rough jagged. Concrete will bond to it better.

[@mattchibi]

Great tip, thank you! Young carpenter in remodeling industry

[@Pembroke.]

Rob how would this apply if you have a concrete floor?

[@SoilentGr33n]

Finally someone using joist hangers.

[@gillgetter3004]

Hey did that before. Thanks for reminder. Like newel posts on stairs.

[@sethdistler5332]

Great idea. Just a heads up for everyone liquid nail is garbage. Loctite 8x or even 3x is the best glue you can get for strong load flex applications.

[@jerryjohnsonii4181]

Thanks for the knowledge Sir

[@treaustin1]

Great quality as always.

[@teddubois6055]

Great video. I'll use that next time. Also, 2:45

[@Procodilee]

Long lateral load lag bolt from face to contact with other wall halfway works wonders too to save floor cuts

[@Sly_Wolf_1]

Another great informative video. 👍

[@ms.butterfly1578]

how about turning a full bathroom wall to half a wall? wall is there but want to open the room, how do I find out if the beams go thru the floor without tearing it all down

[@cyrilcook5853]

Very clear and concise! Thank you.

[@ConcordCarpenter]

Cyril Cook thanks

[@conantdog]

Hey I like you're joist hangers upside down 👍

[@jeffpowell8308]

Good advice Rob. I was taught to do this 30 years ago. Some things stand the test of time.

[@olgajoachimosmundsen4647]

How can you make it sturdy by only connecting to bottom plate? Can you use a steel bracket to create a good connection?

[@ConcordCarpenter]

Joachim Osmundsen you cant did you watch the whole video? Some folks use plywood but I don’t think it as effective as this method

[@Wroom90]

I watched the whole video. So in your opinion the only way to go, is through the floor-plate and attach into the joists?

[@ConcordCarpenter]

Joachim Osmundsen this is one option that Work’s flawlessly, check out my other video using threaded rod

[@dickhead402]

See bud u did good but how I was taught as a kid with adhesive is to spread it out them old carpenters were hard on me I started that company with him design many houses and walked away to help him out

[@DParks-sq4bb]

Doesn't really help on a slab

[@tatescott8747]

N if it’s a diy project what r the fukn odds that the subfloor is open cmon now

[@robertmorley6866]

I have i-joist running perpendicular. What is the preferred way to attach blocking so I can then attach the studs to the i-joist beneath the sub-floor? Would you recommend attaching the studs with bolts rather than nails?

[@eltonnoway7864]

Great video from a Steve Perry Doppleganger! Thanks

[@essentialdeparture9999]

Did you just say concrete carpenter (3:40)? CC agrees. lol

[@wadesansom]

I came to the comments to see if anyone else heard it, haha.

[@ConcordCarpenter]

Boston accent

[@axebob730]

Same

[@ConcordCarpenter]

Essential Departure no

[@essentialdeparture9999]

@@ConcordCarpenter Alright, fair enough. haha Good video anyway though.

[@yancyjeleniewski721]

What do you do on a concrete basement floor. I have secured a pt 2x4 to floor with Ramset Hammer pins 1-1/2 in deep and toe nailed into a perpendicular cross wall of the shower front. Still wobbly!

[@AnthonyDibiaseIdeas]

Thank you.

[@MarkLeonTanner]

I've been in many homes being built and remodeled, and I've only seen one old timer do this.. It's the right way for sure... Most half walls I could easily knock over because they're just toe nailed together...

[@ConcordCarpenter]

Thanks Mark ..... although it pains me to be an old timer

[@smartthinkerg8129]

Awesome video

[@richardlapoint1845]

I wanna see pouring a concrete half wall on a laminate floor, so i can decide weather i wanna try it or not

[@galenhousley8339]

That was awesome, thank you!

[@eugene9661]

Great techniques.

[@Mantis858585]

In my town, most sub floors are concrete.

[@lightningdriver81]

Nice tip. Just subscribed.

[@ConcordCarpenter]

Lightning Driver thx

[@rickanon9912]

Great for main floor kneewall. But my kneewall will be built in the basement on concrete foundation floor. So obviously no joists to work with.

[@ConcordCarpenter]

Scroll down for your answer - threaded rod

[@elaineparsons3568]

what if the floor is in a basement and concrete?

[@mdp66403]

Those are all effective methods, but overly complicated. If wall thickness is not an issue a better method is to sheath the half wall with 1/2” plywood on both sides. You have to use construction adhesive on all of the studs, top plate, bottom plate, and use plenty of nails too. Make sure to keep the wall braced so that it stays plumb while assembling everything. In 24 hours it will be the stiffest half wall you’ve ever seen.

[@ConcordCarpenter]

Marc Pagnucco plywood is an option but I’m not sure it’s better, the wall can still move

[@jamesstrickland8893]

what about a concrete foundation where you don't have access from below?

[@smurray470]

great video! I'm having a little trouble visualizing what you mention for "For additional lateral support, adding 2x solid-blocking, onto the floor joist, on either side of the 2x4 wall stud will add more stiffness, and support to the structural screws. [This is a common method in reinforcing 4x4 posts in deck framing.]". Would these two 2xs be spanning between joists on either side of the vertical stud, oriented with the 3.5'' side vertical pressing on either side against the stud?, making a "stud sandwich"?

[@summerstevens1345]

What would you do if the floor is concrete were the half wall is getting build to ensure that it is strong and doesn't wobble?

[@ConcordCarpenter]

Answer in comments below

[@palgautefall3328]

Video on half-wall on a roof with concrcreas floor? Or a floor that you cant attatch the studs like you showed inn this video 😊

[@jeremiascarrizales6240]

I need to find more homeowners that are willing to pay for this type of work. Most want the best quality but don’t like the price.

[@ConcordCarpenter]

Jeremias Carrizales you have to find a balance and market it

[@thomasdoherty6876]

What if the half wall is installed on a concrete floor?

[@billeddy4357]

Thomas Doherty -- Build a sturdy wall , with 2" by 6" plates and studs .Keep the studs 12 " apart rather than a typical spacing of 16 " . Put blocking on top of the bottom plate , between the studs . After sliding the wall in place and TACKING it so it will stand up , drill holes in the wall , through the top plate , the blocking and bottom plate , because you are going to run a vertical piece of 1/2 " threaded rod through those holes. Use the drill going through the bottom plate to " scratch up " the concrete floor. Then set the wall aside and drill holes in the concrete using a masonry drill , where you have " scratched them up " with your wood drill . Put anchors in the floor , that will eventually be used to lock in the bottom end of the threaded rod . You can then run a piece of 1/2 " threaded rod through the top plate , through any blocking , plus through the bottom plate . You anchor the threaded rod at the bottom with the anchor and at the top with a washer and a nut . At the bottom you may have to use a union to tie the rod to the anchor . ( You do have to use a bit to open up a hole at the top of the plate where the nut can " hide " rather than stick up . )

[@ConcordCarpenter]

Thomas Doherty use threaded rod or 5/8 x 8 bolt epoxied in and a Simpson HDU16 on the stud

[@denisoneill2117]

What type of wood ? Studs are fir, though softwood no?

[@JJBATEAST]

Hey are those woodpecker squares that's behind you really worth the money?

[@ConcordCarpenter]

JB100 very nice

[@HiveMind2024]

screws not nails ... build it like mike holms

[@Xmonders]

That was great info 👍 Thnx for sharing

[@madcowusa4277]

Leave top plates off pony wall, drywall or sheath both sides and fill every third stud bay with concrete and a length or two of vertical 1/2" rebar. Apply top plates. Zero flex.

[@RikoRey92]

Here in FL the floor is concrete

[@rlight7198]

Hey hey hey! What about a half wall on a cement floor!!?!???

[@th3b0yg]

Was the tool shown at the beginning of the video a screw gun with a magazine? It didn't sound like a nailer....

[@ConcordCarpenter]

Robert Johnson framing nailer

[@feralbigdog]

newer ones are battery operated, not as fast as a pneumatic but its more portable

[@cathyfoleyeufrazio9233]

Good stuff thanks!

[@joelfew823]

fuck yeah! thanks dude solved my dilemma.

[@Salve_Regina8]

Build that Wall !!

[@juginstr1019]

Great job!.Thank you.

[@jasonsinclair4482]

And on a concrete slab???

[@mamawlife7852]

Okay. I want to put up a wall in my dinning room and do not want to put holes in my floor, it doesn't have to go up to the ceiling because other walls in the living room dinning room don't go up all the way. On the wall, there will be cabinets on one side and shelves on the other. Can I just attach to the side walls. Note, there will be a door in the center. Help If I ever sell, I want the new owner to be able to remove the wall and have the dining room back with no floor damage.

[@ConcordCarpenter]

if it goes to the ceiling you'll have 2-points of contact - should be all set

[@MistAtsiM]

I just use simpson strong tie brackets... Solid as concrete when done.

[@MeganChic]

How do I do this on a concrete slab?

[@ConcordCarpenter]

see answer in other comments

[@Burritosarebetterthantacos]

I have an 8 ft pony wall, aka a bad idea.

[@shenalally2214]

Mine wobbles until I drywalled it

[@earlfordo4502]

What would you do on a concrete subfloor??

[@truckerdaddy-akajohninqueb4793]

Is that nailer battery operated? How do you like it? Does it have a mini compressor? I still prefer air tools. Even my site drill. I'm not convinced by battery tools.

[@ConcordCarpenter]

Trucker Daddy - AKA John in Québec battery

[@truckerdaddy-akajohninqueb4793]

@@ConcordCarpenter do you prefer it?

[@stevegagnon9451]

Trucker Daddy - AKA John in Québec it’s an ok gun, I have the framing nailer and the hanger nailer both from Dewalt , they have their pros n cons ..... great for framing floors, but slow for framing walls or sheeting

[@lesleygalaida5230]

Any advice to go over and existing rail for additional support vs removing the loft railing to create an entirely new pony wall for privacy? I don't want to increase the footprint but exploring the additional security of going over the existing railing. Thoughts?

[@am11744]

What if the floor is concrete?

[@ConcordCarpenter]

A wood worker see comments below

[@thornieves3624]

I don't understand why you have to block love your videos

[@ConcordCarpenter]

Thor Nieves huh? What’s block love mean?

[@thornieves3624]

I should have put a period I'm sorry

[@markcallahan3605]

Blocking would serve as attachment points for wall studs when the half wall runs parallel to the floor joists.

[@ConcordCarpenter]

Mark Callahan Did I say it wrong?

[@thornieves3624]

@@ConcordCarpenter you guys are awesome

[@nicholasforemann5459]

Great tips

[@joshmckenzie3134]

What if it’s a concrete subfloor

[@ConcordCarpenter]

Your answer is in the comments below

[@irvingg.1437]

Ok how do you strengthen a half wall on a cement floor?

[@micpic119]

Good question. Ran into this a lot doing commercial or slab homes.

[@ConcordCarpenter]

mic pic I answered in another question below

[@micpic119]

@@ConcordCarpenter Thanx!

[@denisoneill2117]

How do you do this with engineered I-joists?

[@simonrizk4451]

thank you sir

[@zeckham100]

What if it’s a concrete floor?

[@ConcordCarpenter]

Answer is below in the comments

[@BJBaker-oh4gt]

What if your attaching to cement foundation

[@ConcordCarpenter]

Answer below in the comments

[@Ruso_Moose]

what if you're building a half wall on a concrete slab?

[@ConcordCarpenter]

Answer is in comments below

[@Paulie1232]

How do you build a strong half wall if your lazy..

[@ConcordCarpenter]

Paul delegate it to someone else

[@truckerdaddy-akajohninqueb4793]

The English pronunciation of your French name is different. I live in Québec.

[@ConcordCarpenter]

Trucker Daddy - AKA John in Québec yes

[@michaelnicolichuk1923]

what if its over a concrete floor?

[@ConcordCarpenter]

Michael Nicolichuk use threaded rod or 5/8 x 8 bolt epoxied in and a Simpson HDU16 on the stud

[@BlueTurfer]

I have engineered joists. Any advice?

[@ConcordCarpenter]

Blocking if you can get access

[@thebnbaldwin]

What do you recommend if you can't open up the flooring and the wall has to float on the surface?

[@ConcordCarpenter]

Brian Baldwin cash the check quick - Just kidding glue and screw every component then use plywood

[@lynndalbertis5433]

@@ConcordCarpenter Using 2 x 3 s and then cover the frame with plywood. I can't get through my floor either

[@lynndalbertis5433]

I should have used a ?? !!

[@ConcordCarpenter]

@@lynndalbertis5433 if you’d using WEDI panels you can glue them to the inside wall - stiffens nicely

[@alejandroespino1998]

Hey man not trying to be a dick but i got a serious question, will upside down joist hangers even pass for inspection? Also i notice in the first part you didnt use a one piece bottom plate, as far as i know, i thought they had to be one piece, like i said, im not trying to be a douche and please correct me if im wrong because i dont wanna go around saying the wrong stuff. I like the idea of a sturdy pony wall but anytime i build them, i just have a concrete slab to work with and another wall to tie into, it works okay but nothing make me feel more confident than no wobble

[@mattmiksch3587]

Any thoughts on a half wall built on a slab foundation? I've thought, not tried yet, sheeting the wall with plywood...... Especially if the final thickness isn't critical.....

[@ConcordCarpenter]

Matt Miksch steel braces or threaded rod or 5/8 x 8 bolt epoxied in and a Simpson HDU16 on the stud

[@exnjute]

In my basement I first glued(I prefer Loctite Poly adhesive) a pressure treated 2 x 6 to the floor and shot it to the concrete with a Hilti gun. Then let the adhesive cure for 2 days. Note - I framed the whole 1/2 wall with 2 x 6's. Then I built the 1/2 wall(32" x 7') flat on the floor using poly adhesive on the bottom and top of each stud as well as three 3 1/2" screws into the top and bottom of the wall. Let that cure for 2 days. Then glued and screwed the 1/2 wall to the bottom plate that I had glued and shot to the floor. Note - When screwing and gluing the 1/2 wall to the bottom plate I inserted 4 screws in each stud bay near the outside edges(1/2" in). I then cut blocking(tight) and glued and screwed those between the studs on the bottom. Be sure to use nice straight 2 x 6's and inspect to be sure crown is up. You can also use threaded rod epoxied into holes drilled in the concrete but I would have had to buy the epoxy, the cement bit and the rod. I installed an 18" granite eating bar on top of the 1/2 wall.....came out awesome. Wall is rock solid, no deflection or wiggle at all. I am "old-school" and like to over build on something like this.

[@ConcordCarpenter]

see answer another comments

[@augie1g]

what if you're on a concrete slab?

[@augie1g]

saw below - thanks!

[@antb1617]

What to do on conrete foundation?

[@ConcordCarpenter]

Ant B your answer is in the comments, below

[@antb1617]

@@ConcordCarpenter i watched the video and I like what you did on the wood frame me being a carpenter my whole life my first instinct was what about the concrete and I went straight to the messages now that I've looked I' see im not the only one that had that question keep up the good work man

[@Random_Things1001]

What? No kreg jig?!