Howdy Glenn and everyone else,
I had another footing poured under my poor ol' perennially sagging home. They put a nice looking footing in, using perhaps 8 or 10 bags of concrete.
They dug down to what they called "refusal"--a term which (I think) indicates nothing real solid (like bedrock)--but to a point that the soil won't 'go anywhere'. Makes sense, I guess.
They poured concrete in the hole, put a layer of rebar, more concrete, then another layer. So, 2 horizontal layers rebar total; nothing vertical.
Does this make sense? This will support important vertical members under the middle of the home.
Thoughts? It sounds OK to me I guess, but would still appreciate a second opinion. Thanks in advance!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
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Hi K2,
What size is the footing (length, depth, and width)?
Also tell me what size rebar they used and how many on each layer if you know.
If it is a square footing for a column or pier, the rebar should be tied together to create a mat. This is done by using an equal number of bars for the top and bottom of each mat turned 90 degrees from each other and tied together with tie wire. The spacing is usually between 6"-8" apart.
The bottom mat should be about 3" from the bottom of the excavation and at least 2” from the sides of the excavation. Aside from giving the concrete the proper reinforcement the minimum of 2”-3” of concrete on all sides helps prevent rust and corrosion. The top mat should be placed approximately 2"-3" from the top of the concrete. "Floating" the mats into the wet concrete is OK and should work fine provided they are in the proper location however it is usually better practice to support the mats in the proper location before the concrete is poured using concrete bricks and/or wire "chairs". Then you can be sure the mats are properly located and will stay in place as the concrete is being poured.
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
What size is the footing (length, depth, and width)?
Also tell me what size rebar they used and how many on each layer if you know.
If it is a square footing for a column or pier, the rebar should be tied together to create a mat. This is done by using an equal number of bars for the top and bottom of each mat turned 90 degrees from each other and tied together with tie wire. The spacing is usually between 6"-8" apart.
The bottom mat should be about 3" from the bottom of the excavation and at least 2” from the sides of the excavation. Aside from giving the concrete the proper reinforcement the minimum of 2”-3” of concrete on all sides helps prevent rust and corrosion. The top mat should be placed approximately 2"-3" from the top of the concrete. "Floating" the mats into the wet concrete is OK and should work fine provided they are in the proper location however it is usually better practice to support the mats in the proper location before the concrete is poured using concrete bricks and/or wire "chairs". Then you can be sure the mats are properly located and will stay in place as the concrete is being poured.
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
Hi Glenn,
Thanks for the response!
Actually I'm feeling a bit better already after reading your response. Even if it's not 100%, I think he did a fairly decent job of it.
The footing is approx. 24" square and about (I guess) 10" or 12" deep.
Each mat is wired, but the mats are in no way connected to each other. So, two horizontal mats. I believe there are 5 pieces of rebar in each mat: kind of like a square with one one-way piece in the middle. (Like an "H" that's been closed off top and bottom.)
I'd say the rebar is less than 1/2" diameter (about 3/8", I guess). He did lay 2 mats at right angles to each other. He put the first (lower) mat down after having put some concrete (I guess 2"). I'd say 2" of concrete on the sides of the mats. Yes, they're floated in there (nothing to hold them in place) but I don't guess they moved much.
I guess my biggest 2 questions after reading your post are:
1. Is it pretty typical for this footing to be dug down in the dirt--but not to bedrock or anything more solid?
2. So it's not necessary to have vertical rebar as well? (I gather it might even have a negative effect?)
I must admit that reinforced concrete is a bit of a mystery to me.
Tomorrow will be the day! A new steel post will be put on it. There'll definitely be pressure on this thing!
I'm hoping to keep him from doing too much jacking at once. For one thing, I can't stand the sound of jacking a house (especially mine). And I'm more concerned to stop settling--rather than jack the house to "level." I wonder if that might do more harm than good...
Thanks again for your response Glenn! I will keep you "posted." (Sorry, bad pun.) And by all means, if you think of anything else, I very much appreciate your comments!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
Thanks for the response!
Actually I'm feeling a bit better already after reading your response. Even if it's not 100%, I think he did a fairly decent job of it.
The footing is approx. 24" square and about (I guess) 10" or 12" deep.
Each mat is wired, but the mats are in no way connected to each other. So, two horizontal mats. I believe there are 5 pieces of rebar in each mat: kind of like a square with one one-way piece in the middle. (Like an "H" that's been closed off top and bottom.)
I'd say the rebar is less than 1/2" diameter (about 3/8", I guess). He did lay 2 mats at right angles to each other. He put the first (lower) mat down after having put some concrete (I guess 2"). I'd say 2" of concrete on the sides of the mats. Yes, they're floated in there (nothing to hold them in place) but I don't guess they moved much.
I guess my biggest 2 questions after reading your post are:
1. Is it pretty typical for this footing to be dug down in the dirt--but not to bedrock or anything more solid?
2. So it's not necessary to have vertical rebar as well? (I gather it might even have a negative effect?)
I must admit that reinforced concrete is a bit of a mystery to me.
Tomorrow will be the day! A new steel post will be put on it. There'll definitely be pressure on this thing!
I'm hoping to keep him from doing too much jacking at once. For one thing, I can't stand the sound of jacking a house (especially mine). And I'm more concerned to stop settling--rather than jack the house to "level." I wonder if that might do more harm than good...
Thanks again for your response Glenn! I will keep you "posted." (Sorry, bad pun.) And by all means, if you think of anything else, I very much appreciate your comments!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
Sounds like they did OK K2. No need for vertical bars in that type of footing unless a masonry pier was used on it.
One more thing you should be aware of:
The load should not be placed on a concrete footing for about 7 days after it is poured. The concrete should be allowed to reach at least 60% of its design strength before placing a load on it. this generally takes 6-7 days.
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
One more thing you should be aware of:
The load should not be placed on a concrete footing for about 7 days after it is poured. The concrete should be allowed to reach at least 60% of its design strength before placing a load on it. this generally takes 6-7 days.
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
Hi again Glenn,
It's been several weeks since it was poured...I think about 6 weeks. So hopefully it'll hold together.
Another interesting thing is that they had fabricated steel brackets (out of 1/4" steel) to place under the beam at the OUTSIDE walls. These brackets will attach to the concrete foundation (using Red-Head concrete anchors) and will replace a couple of other crummy looking footings.
If you have any experience with these I'd also appreciate it.
But my guess is that the outside walls don't carry anywhere near the load of that central footing.
I'm hoping that these efforts will finally put my home's settling issues to bed.
Any input on the actual jacking? (How fast to go, etc.?)
It's been an interesting experience....but one I'd rather not go through again anytime soon :)
Thanks again Glenn! All the best from Golden, CO!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
It's been several weeks since it was poured...I think about 6 weeks. So hopefully it'll hold together.
Another interesting thing is that they had fabricated steel brackets (out of 1/4" steel) to place under the beam at the OUTSIDE walls. These brackets will attach to the concrete foundation (using Red-Head concrete anchors) and will replace a couple of other crummy looking footings.
If you have any experience with these I'd also appreciate it.
But my guess is that the outside walls don't carry anywhere near the load of that central footing.
I'm hoping that these efforts will finally put my home's settling issues to bed.
Any input on the actual jacking? (How fast to go, etc.?)
It's been an interesting experience....but one I'd rather not go through again anytime soon :)
Thanks again Glenn! All the best from Golden, CO!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
Just take it slow and steady. The main thing is to use several jacks and jack the girder up evenly and in small increments. Keep checking doors and windows over the area being jacked up to insure they do not get into a bind. Unlock all the windows and open them slightly to help keep them from binding and breaking the glass.
It sounds like your contractor knows what he is doing.
Good luck
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
It sounds like your contractor knows what he is doing.
Good luck
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
Thanks again Glenn!
I can't tell you how much I appreciate your opinion on this. I've been driving myself crazy over this project (ok, much more so than most of my other projects--which also drive me crazy!)
Take care!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
I can't tell you how much I appreciate your opinion on this. I've been driving myself crazy over this project (ok, much more so than most of my other projects--which also drive me crazy!)
Take care!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
Happy to help K2.
Good luck with your project.
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
Good luck with your project.
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
Hi Glenn,
Just wanted to give you a little status report.
Actually, all went quite well that I can tell (knock on wood). I worked with him on it and found the work to be strangely satisfying.
I was most surprised by the fact that this work is more about "finesse" than "brute force." We didn't actually do all that much jacking...it was more about replacing some crummy posts. As I'd mentioned, we'd already put in a couple of new footings (one of which will bear quite a bit of weight).
They also had fabricated 3 welded metal brackets to attach to concrete foundation wall. Two of these bracketed the main girder (made up of 4 2x12's) (to keep it from twisting, mostly); the other went underneath a triple-joist. We hung these with "red heads" (kind of like large, heavy molly-bolts for concrete). We used his "Bosch Brute"....a great hammer drill; worked so well I think it should be called a "*****cat" instead of "brute." (OK, that probably wouldn't do much for marketing!)
As I mentioned, we didn't do much jacking. The house sags about 3/4" or so in the middle and my main concern was keeping it from sagging any more. As this fellow said, houses can behave differently when they're going "up" than when they're going "down." As the physician's code says, "First, do no harm" and he's a big believer in that. OK with me!
Only repercussion I see so far is that the front door's bolt doesn't want to lock now. This has been an ongoing problem anyway and I've shimmed its hinges a couple of times over the years. Maybe the front door will act more predictably in years to come.
Anyway, that's my report. Thanks again for your assistance Glenn! And any further feedback, of course, is welcome!
All the best from Golden, CO!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
Just wanted to give you a little status report.
Actually, all went quite well that I can tell (knock on wood). I worked with him on it and found the work to be strangely satisfying.
I was most surprised by the fact that this work is more about "finesse" than "brute force." We didn't actually do all that much jacking...it was more about replacing some crummy posts. As I'd mentioned, we'd already put in a couple of new footings (one of which will bear quite a bit of weight).
They also had fabricated 3 welded metal brackets to attach to concrete foundation wall. Two of these bracketed the main girder (made up of 4 2x12's) (to keep it from twisting, mostly); the other went underneath a triple-joist. We hung these with "red heads" (kind of like large, heavy molly-bolts for concrete). We used his "Bosch Brute"....a great hammer drill; worked so well I think it should be called a "*****cat" instead of "brute." (OK, that probably wouldn't do much for marketing!)
As I mentioned, we didn't do much jacking. The house sags about 3/4" or so in the middle and my main concern was keeping it from sagging any more. As this fellow said, houses can behave differently when they're going "up" than when they're going "down." As the physician's code says, "First, do no harm" and he's a big believer in that. OK with me!
Only repercussion I see so far is that the front door's bolt doesn't want to lock now. This has been an ongoing problem anyway and I've shimmed its hinges a couple of times over the years. Maybe the front door will act more predictably in years to come.
Anyway, that's my report. Thanks again for your assistance Glenn! And any further feedback, of course, is welcome!
All the best from Golden, CO!
Regards,
-k2 in CO
Moderator, Miscellaneous Forum
http://www.bobvila.com/BBS/Miscellaneous
Glad to hear all went well.
If you should decide you want to take out the sag later you can always jack it up 1/4" at a time over a period of several months. By doing it slowly over an extended period of time you should have no problems other than adjusting a few doors.
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
If you should decide you want to take out the sag later you can always jack it up 1/4" at a time over a period of several months. By doing it slowly over an extended period of time you should have no problems other than adjusting a few doors.
Glenn
Moderator: Construction Systems, Foundations, and Masonry & Stone
For more information about me and/or my qualifications please visit my website at:
www.consultationdirect.com
