How can a toilet come loose like this?

Toilet is at least 25 years old. One of the good ones, with big tank and lots of flushing power. Sits on a concrete slab floor, vinyl tile. Never had a problem with it beyond a few minor leaks, replacing the float & fill mechanism, etc. Rarely clogged.
So, the other day, I accidentally bumped against it and it MOVED a good half inch on the floor.
I checked the flange bolts and they are loose as can be. I can actually pick the bowl up about 1/4 inch off the floor and set it back down. I haven't taken the bolt covers off yet, so I don't know exactly what the problem might be.
Going to HD on my lunch hour to get a new wax ring and flange kit. Will fix this weekend. But I'm curious about how something that has been so secure for so long can suddenly start to move around like this.
-Frank
--
fwarner1-at-franksknives-dot-com
Here's some of my work:
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Frank J Warner wrote:

Since you haven't looked under the covers, I'm going to make a guess that one or both bolts are rusted through.
Joe
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Frank J Warner wrote: ...

break it loose....
I suspect either the bolts have corroded through or the concrete has spalled to let the bolt loose...
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thu, 03 Mar 2005 13:17:15 -0600, Duane Bozarth

Unless that toilet is REALLY old (pre-1940 or so), the mounting bolts are never set into the concrete. They are set thru the ears or flanges of the closet flange - the top fo the drain pipe.
In many cases of looseness, either the bolts have rusted or the ears have broken or cracked on the flange.
There are reinforcing kits sold that mount behind the flange . New bolts would be inserted thru these reinforcing paltes.
Doug
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Isn't the flange just a slip fit on the sewer pipe?
wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Blue wrote:

Some are, but you have you use one of the two-piece ones (Two "U" shaped pieces) to replace it unless you want to start ripping the pipes apart.
I had exactly the same problem with a dowstairs toilet sitting on ceramic tiles over concrete. The steel flange had rotted away so there was nothing left to hold the heads of the bolts down.
I solved the problem by drilling two 1/2" diameter holes about two inches deep at the proper bolt locations and securing two stainless steel hex head bolts upside down in the holes with "Rockite" expanding cement.
http://www.rockite.com /
(There are lots of other brands of similar stuff.)
I used a strip of wood with two holes in it to keep the bolts vertical while the cement set.
As they say down Maine, "It worked slicker than snot on a brass doorknob."
Jeff
--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'm also going to jump on the band wagon and suggest the bolts on the flange have rusted. Easy to fix.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Rusted bolts, very likely. But before you start your job I would like to suggest a new modern alternative to the wax ring which will leak if the toilet ever moves. The new method is made of PVC with a rubber lip at the top and two O-rings on the bottom. I know that Lowes sells them but they are not on the top shelf like wax rings. They are a few more dollars expensive but it's worth it. They can even be reused.
Frank J Warner wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.