Hump in concrete basement floor
#1
12-26-14, 09:05 PM
Hump in concrete basement floor
Hi everyone. I have a concrete basement floor in a house built in 1913. There is a 12 in x 12 in square hump about 1 in off the ground. It is about 2 ft from a drain in the floor. We are carpeting the basement and I would like to grind down this hump to make it flat, but I don't know what is underneath or what it could be. Anyone ever seen anything like this (picture attached), or have any ideas/suggestions as to what it could be? Thanks in advance for your help!
#2
12-26-14, 09:27 PM
Group Moderator
#3
12-27-14, 05:42 AM
Group Moderator
It could be a repair area or a footer as PJmax mentioned. Grind it down and hope you don't hit anything.
#4
12-27-14, 07:51 AM
Old footing is what I would guess as well. What is above that bump? Is there or was there a beam or is this bump in line with other supporting posts?
Look at all of the sewer lines to judge whether any may be passing under the floor in that area. It doesn't look like a sewer access, but they sometimes include a cleanout.
Bud
Look at all of the sewer lines to judge whether any may be passing under the floor in that area. It doesn't look like a sewer access, but they sometimes include a cleanout.
Bud
#5
12-27-14, 08:01 AM
Thanks for the help. If it is an old footing, would it be safe to try to grind it down so it is flat? Could I do any damage? Or is it better to add some cement to round it off? Thanks again.
#6
12-27-14, 09:05 AM
Ok, I definitely think it is an old footing because upon second look, there are similar (but flatter) bumps in line with this one. Do you think it is safe to try to grind the cement over it?
#7
12-27-14, 09:14 AM
Group Moderator
It's fine to grind this down but if it's an old footing and there are more, I would be taking a quick look up to see if I could figure out what this used to support and whether there are any concerns about posts having been removed.
#8
12-27-14, 09:16 AM
Group Moderator
You should have no problems removing that if it's an old footing. It may take a little grinding or a hammer and chisel to break up.
#9
12-27-14, 09:46 AM
That will be a lot of grinding. One option I have used is a diamond blade for my circular saw. I built a simple frame around the area to be removed so I could slide my saw back and forth at the desired depth. I then cut blade width grooves about every 1/4" and used a cutoff tool to chip away the remaining. For that small area a hammer and chisel would be fine. Then a flat grinder finished it off very nicely.
Not sure what you have for tools. Be prepared for a ton of dust so vent the area and wear a good face mask.
Bud
Not sure what you have for tools. Be prepared for a ton of dust so vent the area and wear a good face mask.
Bud
#10
12-27-14, 09:59 AM
I'm kind of lazy. I'd rent a small electric pavement breaker (jack hammer) and chip out enough to make it about two inches deep then fill with concrete to floor level. Be very careful as you break it up there is nothing under the first two inches.
Last edited by ray2047; 12-27-14 at 12:05 PM.
