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Discussion Starter · #1 ·
Sorry to be long winded

I am currently trying to restore the porch on my 120 year old home. At some point in the history of this porch the cylindrical columns rotted and the roof began to sag in the front (closest to the street). The back is tied into the outer layer of a double wythe brick wall so it hasn't moved. When they replaced the cylindrical columns with the rod iron poles , they put them close to the concrete steps which allowed them to attach a railing down to the frontyard. Because they were close to the steps they were not properly supporting the roof which caused it to sag more. I have jacked the porch up to be level again and installed new fiberglass columns where they are required. Great. However, now my columns are too far (10") from the steps to attach a railing to them.

I plan to add sidewalls to the steps leading up to the porch. Adding the sidewalls will allow me to keep the posts where they belong to properly support to roof and still incorporate a railing from those posts down to the frontyard.

The sidewalls will be 10" thick, 50" long, 40" tall at the back (height of the porch) and 14" tall at the bottom (To support a newel post). Given those dimensions and the angle of the steps, each sidewall will be about 8' square at 10" thick. That's .25 cubic yard per sidewall.

I poured a footer with some 1/2" rebar. I drilled holes into the steps, blew/brushed them out, and epoxied rebar to pin the stairs to the sidewalls. I built the forms. Got a little nervous about a blowout. Added some more bracing. Now I'm ready to mix and pour this thing. It's about 12-80lb bags per sidewall. I'm using quikrete 4000psi mix and a 3.5 cu ft cement mixer.

The last couple things giving me concern are:

1. Should I go for a thick or a thin mix? I understand that slump is the term I should be going for, but I've read many things can affect slump. I will only be able to change the amount of water I use so it's really how thin or thick I make the mixes. I will do the best I can to mix consistently between batches, but I'm not sure if I should go thick or thin.

Thick allows me pull the forms off sooner, but that might leave me with a lot of voids and holes when I pull the forms off.

Thin will ensure I have no voids, but I'm afraid it'll collapse when I pull the forms off.

2. How long to leave the forms on before I can pull them off and finish the sides of the sidewalls. Both sides of the sidewall will be exposed and I'm afraid if I pull the forms off too late, I won't be able to get a decent finish. If I pull them too earlier...well...we know how that will end. I don't plan to do a fancy finish. Float out any imperfections, build a tiny bit of cream, and then lightly brush them with a horse hair bench brush.

Anyone have any advice?

Any red flags?

20,353 Posts
Vibrate the forms on the outside to cause the solids to get away from the form.

This should rid you of the air pockets (voids) near the surface, to not need much tooling at all after the forms are removed.

Try to measure an exact amount of water per bag in the mixer, this will keep it's consistency nearly equal, and a thicker mix is desired to prevent it from being too soupy, and leaking out the corners / joints in the form.

To measure exact, use a bucket marked for the amount of water, and fill the bucket, then pour it in the mixer, never just stuff the hose in the mixer, and say " that's good enough".

It has to be exact water, or you risk a problem either way, too much water, and your pour is weak, from not bonding.

Too little water and it is weak, the same way, as too powdery.

Remember the 7 Ps

Prior Proper Planning Prevents Pi $$ Poor Projects.:vs_laugh:


· Registered
6,737 Posts
line everything up -once you start, don't stop,,, vibration will be a help but don't over-vibrate ( easier said than done for a newbie ),,, don't worry about voids, etc - just pull the forms next day & float out any imperfections,,, every bridge you cross, or travel under, every conc building has had the same problems - what's why there are guys floating abutments, etc
12b per is a stroll in the park

· Hammered Thumb
4,500 Posts
Sounds like you are on your way with your pour. The one thing that stood out is mentioning fiberglass columns. They are dime a dozen, but not all "load bearing" or "structural" advertisements are equal. Some do not have method of attachment for uplift, or lateral rating, or able to mount a handrail to them. Verify that.
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