concrete nosing and formed stairs

[billconner]

I am pouring a patio and one edge sits on a grouted and reinforced retaining wall. I like a nosing on that edge and trying to figure out size. I thought about 1 1/2" wide (projection) and 2" tall. Just not finding much on this detail of forming concrete. Any experience? Thanks.

 

[Zeke]

Build your form to suit the shape with screws so you can remove them in time to finish the edges. A 1 x 6 out side of a 2 x 4 should do it. You won't remove the 2 x 4, just the 1 x 6 to tool the bullnose. Vibrate that area well to not have voids. Keep some wet mud handy to patch and float as you come upon a void.

Overhangs are a matter of timing. I'd build a short mock up and fill it with a sack of ready mix. Actual ready mix won't be rich enough to work well, so if you're successful, you'll be ready at showtime. By adding some more cement it will get better at holding a shape once the form is removed. A WAG would say remove the outside form in about an hour. I'd build the form in short sections for control.

2" is a little thin so your aggregate has to be sized accordingly.

 

[billconner]

Thank you. I could do 2 1/2 or 3 or even 3 1/2. And can live with it being squarish. It's the shadow line I'm after. And I thought about just anchoring as 2x4 as a nosing after slab. It's covering slab edge on top of surface bonded wall I'm after.

 

[rayra]

There are lots of costly edge-form molds available, if you are seeking a particular patterning or look.
Having trouble visualizing the arrangement and effect you are after. WIll the patio slab be capping the wall? Overhanging the wall. Or flush with the wall at the wall face, but with some sort of undercut / shadow line separating slab from wall.

Seconding making the forms for that edge / face readily removable so you can dress that face after the concrete sets sufficiently to strip the forms

I'm casting a concrete countertop with a bullnose edge that will be projecting out over a counter wall which will be plastered and tiled, and am building up an edge form. You could do something similar particularly if your slab edge will be flush with the wall.

 

[billconner]

Top of block wall is 4" below top of slab, and the low edge - 1:48 slope from here. Originally just square edge co-planar with wall, but thought some nosing would be nice. I could live with 4" nosing, thought less would look better. Just planned using an edger to round corners.

 

[billconner]

Have decided to do a 1 3/4"+- (thickness of rough sawn) X 3" high nosing, using 1 by rough sawn and leave the rough sawn texture in the nosing.

Forming stairs are next big challenge. Plan to follow this model: https://www.oneprojectcloser.com/how-to-pour-concrete-stairs/

I please with way SBC retaining wall turned out, willl feel better when it's grouted and reinforced next week.

 

[Zeke]

You need to wire brush the loose fibers off the RS wood or you're going to leave a mess. Treat it well with release.

 

[billconner]

Well, we're pleased. Not easy, and lot of stress. Coolish weather is over 2 hours before we could strip forms and rub the risers.