attaching railings to aluminum columns

[Mbeezo]

I have been asked to bid a deck that is going to have round aluminum colunms with railings running between them. I have installed these types of columns before and know the material is fairly beefy. But still not sure about just a couple of sheet metal screws/self tapping galvinized or some thing like that being enough to feel good about the railings being secured. I looked at a couple of column websites and it seems as if the either dont want to have you install a railing to them or they just let you decide how to do it. So far have not found out a good idea to secure them.

The columns I am talking about a structural columns so there is not post in the middle of them to run a screw into. Suppose I could install some sort of blocking on the inside of the column.

[tjbnwi]

What is the rail made out of?

Tom

[Mbeezo]

railing will be wood. probably fir that we get from a local mill shop. They have a style called Soulard style that is used quite often here in St Louis. Rounded top profile with a dado cut in the underside so you can install a 1x piece of material for baulsters. Bottom rail is almost L shaped so the baulsters are attached on only one side and other side is open for drainage. In other words, half of the dado is cut off so water drains out.

Railing to is maybe 3 inches wide by 2 inches tall. bottom rail something similiar as I recall.

[Happy Home]

Are there surfaces that you can use PL polyurethane adhesive with the sh metal screws ?

There will be a vertical 1x or such attached to the columns ?

[Lavrans]

I'd just be concerned about the screws reacting with the aluminum. You could install with an epoxy and aluminum rivets- big ones.

Like you say, the main question is if the column is rated for the sort of lateral force that a railing is supposed to be rated to. Seems like it should, but... I haven't done that yet so I'm pretty much just guessing.

[tjbnwi]

Pocket type holes. Stainless Tek screws into the columns.

Tom

[kfc510]

Drawing of Soulard style handrail, courtesy of the City of St. Louis:

http://stlouis-mo.gov/government/dep...ard_rail-2.pdf

As far as mounting them, what if you suspended a cup or something from a wire inside the pipe and filled it up with concrete or grout? Then you could anchor into that, or even pre-set your anchors before filling?

kevin

[Mbeezo]

that is exactly what the railings look like. As you can see there does not appear and it is not just apperance, to be a lot of meat to fasten thru. Plus with a rounded column you have even less area.
I do suppose you could figure out a layout that would look acceptable and have the last baulsters set right against the column so you could attach thru that with screws also.

not sure I understand your comment about filling with concrete plus not sure that would be able to be done. Top of column rests against the ceiling area and actually supports the roof. And it is a 0 ft column 12 inches around. Lots of concrete to dump down a column.

[tjbnwi]

Because the column is round, you will be fitting to a circle. Once you fit the top and bottom rails in place they should not move in or out of the space, only up and down.

I don't like the looks of balusters at the posts.

If your 0 feet is 10 feet, about 8 cubic feet of concrete per column.

Tom

[kfc510]

not sure I understand your comment about filling with concrete plus not sure that would be able to be done. Top of column rests against the ceiling area and actually supports the roof. And it is a 0 ft column 12 inches around. Lots of concrete to dump down a column.

How were you thinking of getting blocking inside the column? If you can get blocking in, you can get concrete in. And you'd really only need the concrete in the area you're attaching to, hence the stopper on bailing wire idea- lower something in there past the height of the bottom rail, and fill 'er up to above the top . Not saying it's a great idea, just spitballin' here...
k

[dgbldr]

The only reasonable way I see to connect THAT rail to THAT column is to have aluminum brackets custom made and welded to the column.

[NW Architect]

First you have to get engineering on the capacity of the gage of the aluminum. Fastener withdrawal and shear, primarily. Then you need to get flexural engineering - can you apply the horizontal load to a thing designed in vertical compression. And you need to make sure that the top and bottom connections can handle the horizontal load.

IF that all works out, then you are down to fastening. Custom aluminum brackets would work, and are probably easiest. If you want to go wood, you'll need some sort of mounting blocks that are concave on the back, to match curve (and taper?) of the column, and flat on the face for the attachment of the railing. (I'd mount a vertical stanchion adjacent to each column, using the mounting blocks)

The easiest mounting would be through-bolting. Countersink the bolt head and nut into the mounting blocks and cover it all up with the vertical stanchion. At corners and ends of run, you would not have mounting blocks on opposite faces of the column. You'd have to live with an exposed bolt head.

You can use galvanized hardware. Isolate all contact points with nylon washers and sleeves

[Mbeezo]

The only reasonable way I see to connect THAT rail to THAT column is to have aluminum brackets custom made and welded to the column.

part of the wrong thinking for me would be ruining the finish on the columns. We would be ordering a factory finish white aluminum column so why ruin the finish by welding something to it?
As far as getting something inside the column I am thinking that since we are installing I could do some careful measurements and make some sort of curved blocking to fit to the inside of the columns. Maybe attach with adhesive, braced a couple of directions and use that to fasten to. I had thought about having some sort of plug turned on a lathe, and installing that. Like that idea much better than concrete.

[S.Joisey]

What does the column manufacturer say, Beezo?

Seems they should have some sort of procedure for attaching railings.

Woops. Just re read your initial post. The manufacturer doesn't say anything.

Not a good sign.

Run a bolt from the inside of the post, and slot the underside of the rails to accept the bolt, same as you would drawing together two sections of rail?

[Dick Seibert]

Maybe attach with adhesive, braced a couple of directions and use that to fasten to.

Mark:

Be aware that the code requires that your rail has to be able to withstand a 200# force, even if your inspectors are not up to code, if someone breaks the rail and is injured you are liable, and their attorneys are going to hold you liable even if the AHJ doesn't.