Woodworking Talk banner

1 - 11 of 11 Posts

·
Jack of too many trades..
Joined
·
214 Posts
Discussion Starter #1
I've got a 1927 front-Gable Brick bungalow. This is the variety where the exterior walls are face brick, 12" thick, and features plaster right over brick on the inside walls.

I'm adding elbow brackets made of 4x4 fir beams to support trellis awnings.

Here's one that I built and mounted back at the start of October.


These brackets are about 30" long. I mounted each using two 6' long 1/2" threaded rods with an expanding collars and a liquid mortar to secure the bolts a couple inches into the exterior mortar. They are not coming out easily, but they are not as solid as I would like.

Because of the the way I built and notched the "rafter" boards and the upper mounting plate, the whole thing is pretty solid. The stress force on the rods is mostly perpendicular.

However, I'm not very happy with the way it's secured. I worry that it wouldn't be that hard to rip off the house if someone climbed on it.

This is the rear of the house, and I plan to build a matching awning for the front, and something similar for my dining room window. I'd like to get the mounting right before I go any further.


The options I can see include:
1) drilling into the face brick and mounting the expanding base threaded rod to the brick. I worry that the large diameter of the rod would break the bricks.

2) using 14-16" threaded rod *through* the exterior wall and secured with a nut and a mounting plate on the interior. This would require me chipping out plaster on the inside and putting several holes completely through the house. However, this is how the porches and the wooden framing is secured to the brick shell of the house.

3) something I haven't though of...

Thanks for any suggestions.
 

·
Registered
Joined
·
12,931 Posts
I like your option #2. Drill right through the brick/mortar. That is the most secure fastening you are going to get.

I do not understand your terminology "face brick." To me face brick is something about 1/2" to 3/4" think that is stuck on over another surface.

I think you will want a good hammer drill to do all of that drilling.

George
 

·
Registered
Joined
·
26,848 Posts
I believe a retro fit of the awning, bolting it all the way through the wall would be the safest. The brick veneer may at some time be insufficient to hold a persons weight anyway. There would need to be some kind of blocking attached to the framing of the wall. The only other thing you could do is drill through the brick and insert concrete anchors with some epoxy. As long as the brick veneer would hold, the awning should. You could route on the top of one of the slats "Not A Step"
 

·
Jack of too many trades..
Joined
·
214 Posts
Discussion Starter #4
Okay, little term confusion. This is not a brick veneer. Solid stuff, I'm not even sure if there's a proper air-gap in my foot-thick walls.

Face Brick in my parlance is the much harder (high fired) brick used for the outermost course. A softer type of brick (basically your hard water-absorbent paver) is used on the inner course(s). Many all-brick houses in the late 19th and early 20th only used face brick on the front to save costs. Houses built on corners (like mine) feature the harder, more expensive brick all the way around.

The overall point is that the stuff is dang hard to drill, even with a hammer-drill. I'm hesitant to even consider it with a 1/2 drill and a 2.5" thick brick. I've seen these bricks crack from smaller holes.

Anyway, I was thinking that a long threaded rod and plaster-fun was likely the right way to go, but I wanted to make sure I wasn't overlooking something easier and less "invasive"
 

·
where's my table saw?
Joined
·
28,556 Posts
I would not trust any brick

Anchors are usually put in the mortar between the bricks. Bricks are fired in an oven and are "brittle" and will fracture if subject to tensile loads.

You should put the strongest anchor at the top of the bracket where the loads are trying to pull it away from the wall....tension. The bottom of the bracket will act as a pivot and it will rotate away from the wall on that support when loaded from above, a compression or shear type of load. A through bolt at the top will be best in my opinion. I would be interested in the inner wall composition ....bricks laid at 90 degrees to the face? :blink:
Like this:
http://www.wisegeek.com/what-is-a-flemish-bond.htm

http://en.wikipedia.org/wiki/Flemish_bond#Flemish_bond
 

·
Old School
Joined
·
24,017 Posts
Acnhors are usually put in the mortar between the bricks. Bricks are fired in an oven and are "brittle" and will fracture if subject to tensile loads.

You should put the strongest anchor at the top of the bracket where the loads are trying to pull it away from the wall....tension. The bottom of the bracket will act as a pivot and it will rotate away from the wall on that support when loaded from above, a compression or shear type of load. A through bolt at the top will be best in my opinion. I would be interested in the inner wall composition ....bricks laid at 90 degrees to the face? :blink:
Like this:
http://www.wisegeek.com/what-is-a-flemish-bond.htm

http://en.wikipedia.org/wiki/Flemish_bond#Flemish_bond
I'm not a mechanical or structural engineer, and neither are you, so why try to sound like one. Describing how to do this project might be better off coming from an engineer in the field. One who can inspect the walls and see what there is to work with, and give 'professional' advice. This could include the type of fastener, and whether it should go in a mortar joint or in the brick.





.
 

·
where's my table saw?
Joined
·
28,556 Posts
dude, you have no clue

I'm not a mechanical or structural engineer, and neither are you, so why try to sound like one.
How arrogant and presumptive of you to think that you know anything about my educational background. I have had engineering classes at the undergraduate and graduate level from a Big Ten University in my study of both Architecture and Industrial Design. I worked in the design and Engineering department of the world's largest Corporation for 30 years. I think that I learned a thing or two about simple structures and forces. Calculus and Strengths of Materials were some of the classes that were required. I still have my books and completed homework with the free body diagrams should you doubt it.

This is not structural engineering, it's high school physics.
Open your upper kitchen cabinet door, and hang on it with your full body weight. It will "probably" pull out at the top hinge. Why? Because that's how the forces are acting on the attachment points.
The maximum tension/pulling force is at the top attachment, the bottom attachment point acts as a pivot. Simple. No structural engineering required to understand that.

Why don't you confine your comment to helpful suggestions to the OP, rather than personal attacks on fellow members which you seem to do on a regular basis? Stick to the things you may have some expertise in, like cabinet making.... :boat:
 

·
Old School
Joined
·
24,017 Posts
How arrogant and presumptive of you to think that you know anything about my educational background. I have had engineering classes at the undergraduate and graduate level from a Big Ten University in my study of both Architecture and Industrial Design. I worked in the design and Engineering department of the world's largest Corporation for 30 years. I think that I learned a thing or two about simple structures and forces. Calculus and Strengths of Materials were some of the classes that were required. I still have my books and completed homework with the free body diagrams should you doubt it.

This is not structural engineering, it's high school physics.
Open your upper kitchen cabinet door, and hang on it with your full body weight. It will "probably" pull out at the top hinge. Why? Because that's how the forces are acting on the attachment points.
The maximum tension/pulling force is at the top attachment, the bottom attachment point acts as a pivot. Simple. No structural engineering required to understand that.

Why don't you confine your comment to helpful suggestions to the OP, rather than personal attacks on fellow members which you seem to do on a regular basis? Stick to the things you may have some expertise in, like cabinet making.... :boat:
My comments are not intended to be a "personal attack" as you put it. No need to get into a back and forth argument like you've started that will hijack this thread. The fact is that you aren't an engineer, and assume no liability for work done as you might suggest. This same type of advice applies to electrical questions. There are some topics best left to the OP to get a licensed engineer, or electrician on site to evaluate the conditions.

EDIT: If you need to discuss this further...send me a PM.





.
 

·
Jack of too many trades..
Joined
·
214 Posts
Discussion Starter #10
Guys, don't get too worked up. I really appreciate both of your insights. I recognize that the force is highest on the top. I couldn't use the correct terms, but I've made enough mistakes in my life to see how "things fall down"

"Red Heads" are the product I used to secure these brackets. I typically use this product in concrete to secure post bases and whatnot. My mortar is about 1/2" thick, so the expectation is that the expansion rings would "bite" into the deeper bricks behind the face brick.

I used a liquid mortar filler to help "cement" them in the brick about 2.5" deep. They are solid, but since they are in mortar, I'm not taking full advantage of the strengths of this holding device.

These do hold the brackets on their own, but I'm not completely comfortable with it. The rafter boards are screwed to the faceplate from the rear, notched and screwed to fit over the beam between the brackets, and the whole rafter assembly thing is screwed w/ 3" exterior grade screws into the mortar joints above the window.

Bottom line is that I reduced the stress on the brackets by securing them to the rafters - both with holding devices and interlocking parts.

I like the suggestion that I use a through-rod on the top hole only is very good. I'll likely have to go through my city permits division for the dining room window (as it overlooks a public sidewalk).

I'm investigating the topic with multiple sources (and I know a professional brick mason) so I won't do anything based solely on advice I get here.

I'm not an engineer, but I do have several years of experience in Architectural History and about 14 years of casual research into Arts&Crafts-Era homes and their construction.
 

·
Jack of too many trades..
Joined
·
214 Posts
Discussion Starter #11
Anchors are usually put in the mortar between the bricks. Bricks are fired in an oven and are "brittle" and will fracture if subject to tensile loads.

http://www.wisegeek.com/what-is-a-flemish-bond.htm

http://en.wikipedia.org/wiki/Flemish_bond#Flemish_bond

The wisegeek link is now about Low-Country folks meeting up.

My brick pattern looks more like a Flemish Stretcher Bond.

I don't have easy access to the interior brickwork, but I suspect that I've got something similar on the inside. These bricks are about 4" wide and 9" long, with overall wall thickness of 12" so I expect that there is overlap between inner and outer course where the bricks are turned 90 degrees off.
 
1 - 11 of 11 Posts
Top