Menu
What's new

What do you know about anchors?

Rennie Heuer

Rennie Heuer

Moderator
Staff member
Messages
11,821
Location
Constantine, MI
My next project is a bit outside the guardrails for me. It's a handrail built of red cedar and cypress. It's going on the back porch of the home I installed the two A&C fireplace mantels, the built in entryway bench, and several pieces of furniture.
8.jpg8c.jpgIMG_2470.JPEG

I need to securely anchor the ends to a 105 year old brick wall and the post to recently installed limestone. I'm scared to death to be drilling into this stuff and want to make sure I do it right with no chance of damaging either.

I don't care much for the single point connection of some post anchors as I believe they will allow some movement if leaned on, so I am looking at those that have multiple attachment points. I'll be attaching the end of the railing directly to the brick.


Post Exploded base.jpgPost Exploded.jpgWall attach 1.jpgWall attach 2.jpg


I met with the mason that did the work and he was no help. So I'm doing the research. I'm leaning towards using anchors in epoxy. The wedge anchors scare me as I do not wish to break off a piece of the new lime stone or shatter one of the bricks because I tightened it down too much.

I’m not sure if I’m heading in the right direction so I come here for some wise sage advice from those of you who have done this before. which way to go?
 
If it was my house.. I'd be real tempted to put in small curbed concrete bases adjacent to that porch and anchor the posts down to that, especially as you're box framing them anyway so you could set 2x2 or 3x3 steel box all the way down into the ground and it would be solid as all get out without any worry about the brick or step. You'd have to design some sort of cut in on the boxing around the step lip but that seems.. doable...

What's inside that base under the limestone? If I HAD to drill into the limestone I'd use a wet core bit and go nice and slow with lots of clean out so I didn't wedge it and crack it while drilling. My main concern there is what's under the limestone veneer and how well that will anchor the railing.

I think if you HAVE to go into the brick I share your fear of the brittleness of some of that old brick, so maybe the epoxy is better.. the other option would be a sleeve anchor which is somewhere between epoxy and a wedge splitting the brick risk wise. if you do go epoxy make sure to clean the hole well so it has clean material to bit into and and check your location five times instead of the usual three :)
 
Ryan Mooney said:
If it was my house.. I'd be real tempted to put in small curbed concrete bases adjacent to that porch and anchor the posts down to that, especially as you're box framing them anyway so you could set 2x2 or 3x3 steel box all the way down into the ground and it would be solid as all get out without any worry about the brick or step. You'd have to design some sort of cut in on the boxing around the step lip but that seems.. doable...

What's inside that base under the limestone? If I HAD to drill into the limestone I'd use a wet core bit and go nice and slow with lots of clean out so I didn't wedge it and crack it while drilling. My main concern there is what's under the limestone veneer and how well that will anchor the railing.

I think if you HAVE to go into the brick I share your fear of the brittleness of some of that old brick, so maybe the epoxy is better.. the other option would be a sleeve anchor which is somewhere between epoxy and a wedge splitting the brick risk wise. if you do go epoxy make sure to clean the hole well so it has clean material to bit into and and check your location five times instead of the usual three :)
Click to expand...
Thanks for the advice. Not quite sure what is meant in the first paragraph about small curved concrete bases adjacent to that porch and anchor the post down to that. I will read it again later and see if I can figure it out. Regarding the lime stone, it is 2 1/4 inches thick. My thought was to drill down about an inch and a half to inch and 3/4 and Epoxy an anchor stud in that hole. I was planning on using four of them. Two would wind up in the mortar line and two in the limestone.
 
Rennie Heuer said:
My thought was to drill down about an inch and a half to inch and 3/4 and Epoxy an anchor stud in that hole. I was planning on using four of them. Two would wind up in the mortar line and two in the limestone.
Click to expand...

Seems maybe shallow? See page 5 here, the spec on even the smallest bolt is 80mm (a bit over 3") in concrete and I'd expect this to be weaker:
I'm sure there's a way to figure out the rating at lower depth/weaker material but I don't know how myself. I'd personally tend to play a bit on the cautious side about a railing with unknowns given the liability involved.

Also my understanding was to avoid the mortar in brick drilling and hit the bricks instead. The mortar is basically lime/sand and tends to degrade with repeated poking and time.. the brick on the other hand is fired so should generally be a bit tougher?

Rennie Heuer said:
Not quite sure what is meant in the first paragraph about small curved concrete bases adjacent to that porch and anchor the post down to that. I will read it again later and see if I can figure it out.
Click to expand...
I was thinking basically dig a hole, 2x2 or 3x3" steel box beam... pour concrete around it. Avoid the limestone and brick altogether and just put the railing posts in alongside the stairs/deck. Make a little form so the concrete finishes an inch or two above the grade of the lower brick walkway, and dome the top of the concrete a tad just to push the water away. Roughly like this ignoring the epoxy bits :)


1694317907452.png
 
For anchoring the rails to the wall, I'd feel confident with an industrial epoxy made for use on concrete. Year ago (I'm talking MANY years ago), I build a courtyard gate for the entrance to my parents' house. (It was one of my high school woodshop projects.) It was solid wood and heavy. We used two regular lag bolt style hinges like the one pictured below into a frame and stucco doorway, but the stucco was at least a couple of inches thick. Since the lag bolt threads were barely going to reach any wood, my dad (the concrete engineer) picked up some epoxy at the local concrete supply company to secure the bolts, and they held fast for at least 45 year until the owner at the time did away with the gate completely.

shopping


I also had some experience anchoring things to brick when I was hanging artwork in LA, but I don't think any of it was in 100 year old brick, and I doubt the wedge anchors we used were under as much stress as that railing could potentially see. I think this zebracorn head was the heaviest thing we attached to brick.
Zebracorn 3 - 600.jpg
 
Rennie Heuer said:
......... Regarding the lime stone, it is 2 1/4 inches thick. My thought was to drill down about an inch and a half to inch and 3/4 and Epoxy an anchor stud in that hole. I was planning on using four of them. Two would wind up in the mortar line and two in the limestone.
Click to expand...
As the loads on these fixings is only lateral should anyone lean or pull on the railing and little or no loads pulling away from the wall your anchor studs should be adequate.
The vertical Newel posts are the items at most risk having no lateral bracing, I prefer to use a ground anchor that provides longer core support rather than just a shallow socket where screws can pull out of the moisture prone post end.
 
You could make an apron around the bast of the post. Anchor the apron to the concrete with good concrete anchors WITH a really good construction epoxy in the anchors.. Use copius amounts of a high quality construction under the base and around the post. I would use PVC (azec) or something complete inert to weather for the base. It can all be painted.
 
Frank Fusco said:
If you can believe the ads, Gorilla glue has a product you can use on bricks just for a project like yours. Personally, I'm skeptical it would be permanent.
Click to expand...
Back in the early 90s, when Gorilla Glue was a relatively new product, I glued a 4X4 gatepost to the side of my stucco house. When I sold the house ten years later it was still there, and still solidly attached.
 
Being in the fastener business for over 40 years (Hilti, Pneutek) I would recommend a sleeve anchor for attaching the post to the brick wall. There is a "sleeve anchor" that has a flat slotted head so the washer and nut would not show on the face of the post. I would use 2 per post. a 3/8" x 5" would do the job. (FS35-5) For the base I would drill a 1/2" hole about 2.5" and epoxy a 1/2" piece of threaded rod with a not and washer thru the base and into the epoxy.
 
What an absolute wealth of information to be found here. I knew I was taking my question to the right place.

Urged on by what was said here I contacted the mason who install the lime stone. Turns out there is 6 inches of concrete below the lime stone. This means I can drill down as deep as I wish for epoxy anchors. I still worry about lateral forces on the railing. my intention is to use a galvanized steel bracket to hold the base of the post. As I said earlier, I don’t think I can trust a single point fastener type of bracket. I will be looking for one that fastens at all four corners. Hopefully, the close proximity of the second post on the bottom step and having the wall anchors only 5 feet away will give it enough rigidity. Come to think of it, having 6 inches of concrete below the steps means I can probably look at expansion or wedge anchors and not have to worry about epoxy. I will have to give this some thought.
 
OK - still fretting over this anchor business.

I can use a pretty healthy anchor bolt in the 6" of concrete below the limestone. 1/2" or so. Plenty strong. Using a single bolt configuration I have some adjustability as well. I'm looking at the Simpson ABW. I like that it connects to the post in 8 places on 4 sides.

ABW44 (inst).jpg ABW44.jpg ABW44RZ_RI.jpg

I still worry about lateral load - people leaning on the rail. Here are the possible pluses.
The rail will be anchored to the wall at one end, only 5' away and the other end has the second post just 18" away on center. Perhaps I'm overthinking.

I also thought about lateral bracing, bring the post down the side of the porch, but it just wont work aesthetically.
 
Thing that bothers me is not the fixing in the concrete but the shallow fixing just gripping the base of the post

I would look into fixings that pass further up the centre core of the post with clamping nut or sleeve nut or through bolts further up from the base.

Anchor.jpg Anchor2.jpg
 
I would place a decorative steel post on either side of the bottom of the steps and another next to each wall and build the rail off of that. What I wouldn't do is drill into the limestone with the expectation that it was not going to crack or break, either while drilling or when someone falls or leans on the rail. People do dumb stuff. I've seen them sit or lean on a handrail 30' off the ground like it was a lazy boy recliner... Sink those posts 3' - 4' and set in concrete and they won't move and you don't have to worry about the integrity of the brick or the limestone.

But, that's just what I would do if I had to do it...

Alan
 
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?

1694899753367.png
 
You must log in or register to reply here.
Top