Removal of Clay-lined Furnace Flew

[Bill]

I'm in a California (Bay Area) house built mid to late twenties.

I have an abandoned furnace pipe that is about 8" to 10" in diameter which has a clay pipe on the inside wrapped in galvanized metal. The pipe sits on the floor of the basement and extends through our single floor and exits the roof through just a framed in dead space in the living area. That is, it's not inside a brick chimney.

It's put together in sections about three feet long and it looks like they are only connected by a slip joint. I'm told the sections weigh about 90 pounds each.

Does this sound right?

What I'm not clear about is how the clay liner pipe is connected to the outter galvanized metal wrap, if at all.

Anyone have experience removing these?

I'm having the roof replaces and the pipe goes up through a false chimney that we plan to remove.

I've had a number of furnace contractors comment about it -- a few of which were sure it was not clay lined (which is it). A few have suggested knocking out the bottom section one by one and letting the pipe fall. Sounds like a bad idea.

Another contractor suggested cutting two 2x4 boards just a bit larger than the inner diameter of the clay pipe. Bold them together in an "X" and insert the thing into the inside of the pipe at an angle so that when pulled with a rope or chain from the center it wedges itself and can be used for lifting a section.

There's about 1" or so between the inner clay pipe and the outer galvanized metal wrap, so another idea was to drill maybe four holes around the outside of the middle of a section and use hooks connected to cable or chain to use to grip the section.

I had an asbestos contractor look at it and they did not belive there was any asbestos in the pipe.

Any suggestions for how to remove this pipe? I'm looking for ideas how to best grab each section, ideas for lifting, and what to do if the sections are bonded from years of sitting there. I'd rather not drop a section through the living room ceiling.

Thanks,

[Kevin O']

Hi,

FWIW, I've seen these removed from within brick chimneys by carefully smashing them up from within and letting the small pieces fall to the bottom to be scooped out. How this is accomplished is by attaching a small ( about

2 pound) hammer-like device to the end of an gradually decreasing length set of extension rods... these are attached to an electric drill and lowered down to the bottom from the top. The drill turns the hammer at high speed inside the shaft, centrifugal energy causes it to contact the pipes surface, smashing up the clay - it's a simple idea, but very effective. The chimney ( or in your case, exterior of the tube) acts like a trash chute, keeping the broken pieces flowing to a confined, controllable space (the bottom of the tube). The upside to this process is that the pieces are now small and can be swept up an carted off easily. Usually this is done in conjunction with replacement of the clay liner pipe with a stainless steel liner, therefore it is designed not to damage the exterior surround.

I would check w/ local tool rental companies for the equipment.

You may also want to have a look inside this pipe before you start - consider buying one of those cheap 2.4 Ghz video cameras that transmit to your tv/vcr and lowering it down the pipe w/ a flashlight - the cost for there things is really low(under $75.00), and it may reveal useful data...

If your goal is permanent removal, this may not be the ideal solution. You would still have to deal with the outer tube - but it would weigh a whole lot less!

Good luck,

Kevin O'

[jim]

sure is a bad idea, all the weight will be on the bottom when the thing comes tumbing down and could possible take the house down or do some real damage... start from the top and work you way down that way you dont have much of a load on anything if it starts to go down, just the one piece that you break off the top.... dont let any contractor do the bottom from the top unless you check out his inusurance policy and make sure you are covered for when he messes up....

[Bill]

The removal was fun.

Started at the roof and worked down. Each section was about three feet long, about 12" in diameter metal outside and a think clay pipe on the inside about 10" in diameter. The clay sections weigh about 45 to 50 pounds each and were mortared together and then a band of metal about 6" wide covered the mortared joint. There were about 12 or 13 sections reaching from the floor of the basement out the roof (single story house).

We would remove the outter galvanized metal a section at a time, then rock the pipe back and forth to break the mortar and then "just" lift. First two sections were done from the roof then two or three more from the attic.

The tricky part was the sections inside the wall on the first floor. We could just reach down far enough to grab one section and pull it up into the attic. For the next three sections we cut a 2x4 just a tiny bit longer than the inside diameter of the clay pipe, added some rubber on the edges for friction and an eye-bold into the 2x4 off center which we attached chain. This board was lowered on a chain into a pipe section and then pulled to (hopefully) wedge (cam) it in the pipe well enough to haul it up. Sounds a bit easier than it was. Half a century of soot makes the inside of the pipe slippery. Again, the sections were mortared together, so to break the mortar one person climbed down into the wall space and stood right on top of the clay pipe and rocked it back and forth.

Kind of amazing no damage was done anyplace.

Removing the few sections in the basement was more sawzall, hammer, and very dirty work than it was tricky.

Anyone need 600 pounds of clay pipe?