What do you know about anchors?

[steve ramsey]

I would install a metal post welded to a base plate and clad the metal post with wood. The problem is that I don't think the limestone provides enough embedment for the needed length of anchors for the required clamping force. What is under the limestone? Can holes be drilled through the limestone into something more solid providing longer anchors with more clamping force?

View attachment 127071

If you use this method you can core drill the limestone and concrete and use por-rock to anchor the post. I've set a lot of steel handrail this way.

Quikrete 20 lb. Anchoring Cement 124520 - The Home Depot

Quikrete 20 lb. Anchoring Cement is a pourable, fast setting, expansive cement that develops strength greater than concrete. This cement expands to fill voids in concrete to ensure that it locks into place. Quikrete 20 lb. Anchoring Cement is used for anchoring essentially anything metal into...

www.homedepot.com

 

[Darren Wright]

If you use this method you can core drill the limestone and concrete and use por-rock to anchor the post. I've set a lot of steel handrail this way.

Quikrete 20 lb. Anchoring Cement 124520 - The Home Depot

Quikrete 20 lb. Anchoring Cement is a pourable, fast setting, expansive cement that develops strength greater than concrete. This cement expands to fill voids in concrete to ensure that it locks into place. Quikrete 20 lb. Anchoring Cement is used for anchoring essentially anything metal into...

www.homedepot.com

And you can hire a coring company to come core them, so they take that liability

 

[Rennie Heuer]

I would install a metal post welded to a base plate and clad the metal post with wood. The problem is that I don't think the limestone provides enough embedment for the needed length of anchors for the required clamping force. What is under the limestone? Can holes be drilled through the limestone into something more solid providing longer anchors with more clamping force?

View attachment 127071

If you use this method you can core drill the limestone and concrete and use por-rock to anchor the post. I've set a lot of steel handrail this way.

Quikrete 20 lb. Anchoring Cement 124520 - The Home Depot

Quikrete 20 lb. Anchoring Cement is a pourable, fast setting, expansive cement that develops strength greater than concrete. This cement expands to fill voids in concrete to ensure that it locks into place. Quikrete 20 lb. Anchoring Cement is used for anchoring essentially anything metal into...

www.homedepot.com

Bill and stele,

This is a great solution, however, I don't think it will be an option. I intend to meetWith the owner again to discuss options. He really did not plan ahead when he had the porch redone. I’m sure we will get it figured out. I am grateful to be armed with all the possibilities raised here.

 

[Rennie Heuer]

I spoke with the client and he's decided to go with boring the limestone/concrete and sinking a steel post! Anxiety defeated... except...now I need to come up with the best way to connect my wood to his steel.

 

[Vaughn McMillan]

...now I need to come up with the best way to connect my wood to his steel.

I think it's safe to say you can scratch "welding" off the list of possibilities.

 

[Rennie Heuer]

I think it's safe to say you can scratch "welding" off the list of possibilities.

= lost client

 

[Rennie Heuer]

well, maby not too bad. Looking at this picture generously supplied here, I can rip down the 4x4 cedar post I was going to use, slicing off the sides and removing the core. Then glue it back together.

 

[Ryan Mooney]

You could also bury a couple of nuts into the inside of the wood wrapper and then use bolts from the outside (thinking basically set screws with a cap over them, maybe lined up with the rail to hide it) to lock it into place. I suspect with two bolts (maybe a pair top & bottom) pressing into the metal post that would keep the wrapper from moving quite well, a dimple in the metal post might also be useful.

 

[Rennie Heuer]

Another change. Cost for boring one 2” hole 8” deep……$600!

So, we’re looking at welding a pipe to a flat 5” square sheet and using 4 smaller anchors.

 

[Brent Dowell]

Another change. Cost for boring one 2” hole 8” deep……$600!

So, we’re looking at welding a pipe to a flat 5” square sheet and using 4 smaller anchors.

Is that the normal price or the "We're too busy and dont really want to do it, but will if you pay it" price?

 

[Rennie Heuer]

Is that the normal price or the "We're too busy and dont really want to do it, but will if you pay it" price?

My client got the price, so, not sure.

 

[Bill Satko]

You could also look at a threaded floor flange. This is one from Home Depot and is for 1-1/2 pipe. I believe this is black iron and you would ideally want it to be galvanized. There probably other ready make solutions that would not require custom welding if that proves to be too expensive. Of course for any ready made solution you need to be careful of the hole pattern of the flange. The size and/or type of anchors you will use will affect the spacing you will need on your flange or base plate. A custom base plate allows you to control all that.

 

[Rennie Heuer]

You could also look at a threaded floor flange. This is one from Home Depot and is for 1-1/2 pipe. I believe this is black iron and you would ideally want it to be galvanized. There probably other ready make solutions that would not require custom welding if that proves to be too expensive. Of course for any ready made solution you need to be careful of the hole pattern of the flange. The size and/or type of anchors you will use will affect the spacing you will need on your flange or base plate. A custom base plate allows you to control all that.

View attachment 127124

This is a VERY good idea! Research time tomorrow!

 

[Bill Satko]

Oh by the way, here is my bike stand that I mounted outside using threaded drop in anchors. I wanted the ability to remove it during winter.

 

[Rennie Heuer]

OK, here's the plan as of today. I'll use 1 1/2' threaded galvanized pipe 36" long threaded into a floor flange. The flange will be anchored using 4 3/8" x 7" wedge anchors. These will lock into the concrete below the 2" thick limestone. I'm going to use this method for all three posts on the porch. I'll wrap the post with 2x6 cedar beveled on the edges. These anchors are top rated -

"ICC ESR-2818, Uncracked Concrete, Cracked Concrete, and Seismic Approved"

I'll use a slightly shorter version on the brick.

I'm not sure what the rule of thumb is for getting too close to the edge of the underlying concrete. I think I'll be between 1 1/2' and 2". Using such a small dimeter anchor I thought that might be sufficient.

Thoughts?

 

[Bill Satko]

Check the specific anchors you intend to buy but in general you need to have 10 anchor diameters for spacing between anchors and 5 anchor diameters from an unsupported edge. I would check if 1/4 anchors would have sufficient pull out and shear strength for you application. This might allow for the spacing you need between each hole and/or the edge of the concrete.

 

[Rennie Heuer]

Check the specific anchors you intend to buy but in general you need to have 10 anchor diameters for spacing between anchors and 5 anchor diameters from an unsupported edge. I would check if 1/4 anchors would have sufficient pull out and shear strength for you application. This might allow for the spacing you need between each hole and/or the edge of the concrete.

Excellent and very useful information. Thank you. I had originally looked for 1/4 inch anchors, but could not find anything longer than 3 1/2” inches. I wanted to make sure I got down deep into the supporting concrete and stayed away from the softer lime stone. I’ll have to continue looking, as the 3/8 would have to be 3 inches from the edge if I follow your formula correctly.

 

[steve ramsey]

This should help.

https://www.fastenal.com/product/Fasteners/Anchors/Wedge%2520Anchors?categoryId=600168

 

[Rennie Heuer]

Thanks all. I think I can go with the 3/8" anchors and stay within proximity limits. I am thinking of using only three of the anchors on the post nearest the edge. By rotating the flange so that one hole is closest to the edge the other three are far enough away from both the edge and each other. My thinking is that three will be plenty strong and the missing one will be on the outside where it would not be called on to do much work as people are more likely to lean into the railing than to pull on it.

Maybe I'm just not thinking straight - this problem has dogged me for weeks.

 

[Ryan Mooney]

Maybe I'm just not thinking straight - this problem has dogged me for weeks.

It's not an easy problem... It'd have been nice if the railing had been planned for in the initial stoop build and appropriate fixtures installed into the concrete base.

I'm reminded somewhat of the pictures you see where the plumbers come by after the framing guys have done their job and just like 6 floor joists in half with nothing left to work with.... Not quite as bad but still..

Edit: I'm not claiming you would do such a thing of course . More that proper planning by the owners up front might have saved you a lot of grief.