If the steel is rusted through to the concrete then you need to replace them.

 

' lally column ' was a proprietary name of conc filled pipes invent'd by john lally,,, his cousin was harry lally - harry wasted his time & was never noted for doing anything other'n being the inspiration for lally-gaggers therefore john is the better known of the 2 cousins :laughing: john's are conc fill'd to add fire resistance so the columns don't collapse when temps rise due to possible fire,,, harry's, hot air

on a lighter note, if the steel's rusted away, there is no solid support,,, any supporting column should be located on its own proper steel reinforc'd foundation.

contractors who encourage replacement are more pro than the others however they may not be aware of conc resurfacing w/polymer-modified cements which may be a viable cost-alternative for your fine garage floor,,, send joe a pm & ask him !

 

I would replace them with perminent lally columns. Not the telescoping ones you can pick up at any hardware store, but single piece columns with just one end with a screw jack. (Most codes don't allow for the telescoping ones for perminent use). You'll have to measure the height and buy the right size. You can order these at Lowes. In some cases, these are actually cheaper than the heavy duty telescoping ones, and have a higher weight limit.

They should be mounted perminently. The way I do it is attach a piece of pressure treated lumber to the floor (there are many ways to do this), then bolt the column to that. It should be bolted on the top as well. I'm sure it goes without saying they have to be perfectly plumb.

Put the adjustable end on the bottom. There are multiple reasons for this, but you'll be much less likely to hurt yourself by pulling a muscle adjusting it down at floor level than reaching over your head or standing on a ladder.

http://www.octoberhome.com/articles/adjustcolumn/adjustcolumn.html
The first type on this page is the type I'm referring to.

Hope this helps.

Billy

 

Thank you for the replies... I'm not sure if these extra facts are relevant, but the existing columns are permanent columns mounted below the floor, presumably into the footer. They certainly continue to "feel" solidly in place even though parts of the metal has rusted completely through. As far as I can tell, the concrete beneath the metal looks fine and fully in tact.

I'm actually trying to get in touch with someone at a column company to get their thoughts as well. I had another contractor last night take a look and insist we didn't need to replace them.

If the columns are well-mounted below the floor, does this make a difference despite the rust? Also, I don't see screws in the top of the column - it looks like they are either pressure fit to the beam or go into the beam. The paint on the column and ceiling make it difficult to tell.

thanks!

 

There's no mistaking the "screw", if you can't see it, it's not there. They make them in fixed length, and can be put in at the time the foundation/footers are pored. The height has to be exact.

If they are rusted through then you have lost some of the structural integrity of the post. A column loses that if it's not continuous. They may be still sufficient. But nothing short of a structural engineer will be able to tell you that for a fact. Any contractors you have come out are just speculating like us on here.

My firm advice: structural engineer or replace them.