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Residential concrete slab help.

jar546

*****istrator
Joined
Oct 16, 2009
Messages
8,027
Location
Palm Beach County Florida
Ok . Can you explain how you can see that?

Wood sole plates at all exterior walls on monolithic slabs, wood sole plates of braced wall panels at building interiors on monolithic slabs and all wood sill plates shall be anchored to the foundation with minimum 1/2-inch-diameter (12.7 mm) anchor bolts spaced a maximum of 6 feet (1829 mm) on center or approved anchors or anchor straps spaced as required to provide equivalent anchorage to 1/2-inch-diameter (12.7 mm) anchor bolts. Bolts shall extend a minimum of 7 inches (178 mm) into concrete or grouted cells of concrete masonry units. The bolts shall be located in the middle third of the width of the plate. A nut and washer shall be tightened on each anchor bolt. There shall be a minimum of two bolts per plate section with one bolt located not more than 12 inches (305 mm) or less than seven bolt diameters from each end of the plate section. Interior bearing wall sole plates on monolithic slab foundation that are not part of a braced wall panel shall be positively anchored with approved fasteners. Sill plates and sole plates shall be protected against decay and termites where required by Sections R317 and R318.
 

Garrett Foster

Garrett
Joined
Jun 8, 2019
Messages
30
Location
Oklahoma
Wood sole plates at all exterior walls on monolithic slabs, wood sole plates of braced wall panels at building interiors on monolithic slabs and all wood sill plates shall be anchored to the foundation with minimum 1/2-inch-diameter (12.7 mm) anchor bolts spaced a maximum of 6 feet (1829 mm) on center or approved anchors or anchor straps spaced as required to provide equivalent anchorage to 1/2-inch-diameter (12.7 mm) anchor bolts. Bolts shall extend a minimum of 7 inches (178 mm) into concrete or grouted cells of concrete masonry units. The bolts shall be located in the middle third of the width of the plate. A nut and washer shall be tightened on each anchor bolt. There shall be a minimum of two bolts per plate section with one bolt located not more than 12 inches (305 mm) or less than seven bolt diameters from each end of the plate section. Interior bearing wall sole plates on monolithic slab foundation that are not part of a braced wall panel shall be positively anchored with approved fasteners. Sill plates and sole plates shall be protected against decay and termites where required by Sections R317 and R318.
Nice thank you
 

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,735
I am going to guess that you decided that contractors know what needs to be done and that you do not need an engineer. Too many small time contractors present themselves as knowing more than they really know. Individuals wanting to build an individual house are their natural prey. Some developers may not be much better.

The only "standards" on acceptable crack widths are promoted by a group of developers and are so generous that you will not find them helpful

While it does not appear that the cracks will cause major problems it should be noted that concrete cracks because of too much water in the concrete and inadequate curing. #3 bars in the slab are totally inadequate to control cracking. My practice was to use a 5" slab with #5 @ 12" OC. I suspect that you will find that the cracks do not occur at the crack control joints which would support my belief that they are not effective. This is why I use more reinforcement than most do recognizing that you generally cannot prevent all cracking but that you can minimize the size of the cracks..

I doubt that the Xypex, which is a good product, will provide you much benefit. Xypex is most effective as a concrete additive. Using Xypex to repair the cracks assumes that the concrete is a major barrier for moisture transmission and the crack is a break in that barrier. It also assumes that there is excessive moisture in the ground that will migrate into the house because no adequate membrane was provided under the slab. Concrete is less effective as a moisture barrier than a good membrane under the slab.

You could provide a troweled layer of Xypex over the whole slab but this will likely create objections where you wish to have exposed concrete floors.

Obviously they placed the footings separately from the slab and did not remove the rock pockets in the footings prior to the second pour. This is a key sign that the contractor didn't know what to do or didn't care.

I would question the number of and location of anchor bolts.

You may find that the end result will be a house not much different from your neighbors and in the absence of major earthquakes or winds will be habitable.

Consult with an engineer to understand what your risks are. Recognize that if you get righteous at this stage you will likely get involved in litigation which will cost you much money and will result in delays. It could be that the cheapest thing to have done was to have an architect and engineer design the building and then hired a different contractor.
 

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,735
1/2" diameter anchor bolts at 6 feet on center are totally inadequate when subject to earthquakes and high winds such a tornados and hurricanes.
 

Garrett Foster

Garrett
Joined
Jun 8, 2019
Messages
30
Location
Oklahoma
1/2" diameter anchor bolts at 6 feet on center are totally inadequate when subject to earthquakes and high winds such a tornados and hurricanes.
Ok. We're on a hill where it gets a lot of wind. Also this is a 2 story house they're trying to build with 2x4 exterior walls.
 

Garrett Foster

Garrett
Joined
Jun 8, 2019
Messages
30
Location
Oklahoma
I am going to guess that you decided that contractors know what needs to be done and that you do not need an engineer. Too many small time contractors present themselves as knowing more than they really know. Individuals wanting to build an individual house are their natural prey. Some developers may not be much better.

The only "standards" on acceptable crack widths are promoted by a group of developers and are so generous that you will not find them helpful

While it does not appear that the cracks will cause major problems it should be noted that concrete cracks because of too much water in the concrete and inadequate curing. #3 bars in the slab are totally inadequate to control cracking. My practice was to use a 5" slab with #5 @ 12" OC. I suspect that you will find that the cracks do not occur at the crack control joints which would support my belief that they are not effective. This is why I use more reinforcement than most do recognizing that you generally cannot prevent all cracking but that you can minimize the size of the cracks..

I doubt that the Xypex, which is a good product, will provide you much benefit. Xypex is most effective as a concrete additive. Using Xypex to repair the cracks assumes that the concrete is a major barrier for moisture transmission and the crack is a break in that barrier. It also assumes that there is excessive moisture in the ground that will migrate into the house because no adequate membrane was provided under the slab. Concrete is less effective as a moisture barrier than a good membrane under the slab.

You could provide a troweled layer of Xypex over the whole slab but this will likely create objections where you wish to have exposed concrete floors.

Obviously they placed the footings separately from the slab and did not remove the rock pockets in the footings prior to the second pour. This is a key sign that the contractor didn't know what to do or didn't care.

I would question the number of and location of anchor bolts.

You may find that the end result will be a house not much different from your neighbors and in the absence of major earthquakes or winds will be habitable.

Consult with an engineer to understand what your risks are. Recognize that if you get righteous at this stage you will likely get involved in litigation which will cost you much money and will result in delays. It could be that the cheapest thing to have done was to have an architect and engineer design the building and then hired a different contractor.
Yes. I'm out of town all the time so I cant over see every day operations. So I hired a building contractor and have seen nothing but inexperienced labor so far.
 

mark handler

Sawhorse
Joined
Oct 25, 2009
Messages
10,877
Location
So. CA
I am going to guess that you decided that contractors know what needs to be done and that you do not need an engineer. Too many small time contractors present themselves as knowing more than they really know. Individuals wanting to build an individual house are their natural prey. Some developers may not be much better.

The only "standards" on acceptable crack widths are promoted by a group of developers and are so generous that you will not find them helpful

While it does not appear that the cracks will cause major problems it should be noted that concrete cracks because of too much water in the concrete and inadequate curing. #3 bars in the slab are totally inadequate to control cracking. My practice was to use a 5" slab with #5 @ 12" OC. I suspect that you will find that the cracks do not occur at the crack control joints which would support my belief that they are not effective. This is why I use more reinforcement than most do recognizing that you generally cannot prevent all cracking but that you can minimize the size of the cracks..

I doubt that the Xypex, which is a good product, will provide you much benefit. Xypex is most effective as a concrete additive. Using Xypex to repair the cracks assumes that the concrete is a major barrier for moisture transmission and the crack is a break in that barrier. It also assumes that there is excessive moisture in the ground that will migrate into the house because no adequate membrane was provided under the slab. Concrete is less effective as a moisture barrier than a good membrane under the slab.

You could provide a troweled layer of Xypex over the whole slab but this will likely create objections where you wish to have exposed concrete floors.

Obviously they placed the footings separately from the slab and did not remove the rock pockets in the footings prior to the second pour. This is a key sign that the contractor didn't know what to do or didn't care.

I would question the number of and location of anchor bolts.

You may find that the end result will be a house not much different from your neighbors and in the absence of major earthquakes or winds will be habitable.

Consult with an engineer to understand what your risks are. Recognize that if you get righteous at this stage you will likely get involved in litigation which will cost you much money and will result in delays. It could be that the cheapest thing to have done was to have an architect and engineer design the building and then hired a different contractor.
If you actually go to the link I provide, they do have a fix for the cracks, which I have specified, and was used and prevented water intrusion into a basement that continually leaked prior to the use of Xypex. don't poo-poo something unless you know.
 

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,735
Being located on top of a hill is less critical than if your area is subject to tornados or hurricanes.

Was a geotechnical report prepared?

2x4 exterior walls limit the amount of insulation in the walls. Many projects use 2x6 in order to accommodate more insulation.

Hire an engineer to help you to understand your risks and develop an approach.. Some times it may be cheaper to pay the contractor to do things different from here on. Sometimes it may be appropriate to get a new contractor but if you go that route consult with an attorney familiar with construction.
 

Garrett Foster

Garrett
Joined
Jun 8, 2019
Messages
30
Location
Oklahoma
I'll pro
Being located on top of a hill is less critical than if your area is subject to tornados or hurricanes.

Was a geotechnical report prepared?

2x4 exterior walls limit the amount of insulation in the walls. Many projects use 2x6 in order to accommodate more insulation.

Hire an engineer to help you to understand your risks and develop an approach.. Some times it may be cheaper to pay the contractor to do things different from here on. Sometimes it may be appropriate to get a new contractor but if you go that route consult with an attorney familiar with construction.[/QUOTE
I'll probably have to consult an attorney. Thank you for all your information.
 

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,735
Mark

I am familiar with Xypex and have used it in repair situations but there is a difference between cracks in walls with water leaking through the cracks and a slab on grade where your concern has to do with moisture migration from the soil to the interior of the residence.

Concrete slabs may slow down the moisture transmission but they are less effective than assumed. In many locations there is not enough moisture under the slab to be a concern. If there is, you normally address it by having a good membrane directly under the slab. If this is not done just repairing the cracks may provide little benefit and you are better off by providing a surface treatment of Xypex on the entire slab.
 

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,735
There is a curse that goes "may you be blessed with a law suite where you are in the right" The reference to an attorney was with respect to firing the contractor. In general it may be that you are better off paying more money and accepting some delays. Avoid litigation. it can be very expensive, result in delays, and be emotionally draining.

It may make sense to accept a less than perfect building than to fight to get perfection.

f you are married make sure that your spouse is supportive. These sort of problems can put a strain on a marriage.
 

jar546

*****istrator
Joined
Oct 16, 2009
Messages
8,027
Location
Palm Beach County Florida
Garrett, I hope that you take the bull by the horns in this situation before you start framing. It is bad enough what we see when there are permits and inspections, when there are no permits or inspections, I could only imagine how lackadaisical construction may be. Good luck. You really need to slow this down and make sure it is all done to the state code regardless of whether or not there is a permit.
 

Garrett Foster

Garrett
Joined
Jun 8, 2019
Messages
30
Location
Oklahoma
There is a curse that goes "may you be blessed with a law suite where you are in the right" The reference to an attorney was with respect to firing the contractor. In general it may be that you are better off paying more money and accepting some delays. Avoid litigation. it can be very expensive, result in delays, and be emotionally draining.

It may make sense to accept a less than perfect building than to fight to get perfection.

f you are married make sure that your spouse is supportive. These sort of problems can put a strain on a marriage.
Thank you. Yes my wife is on board and absolutely disgusted with the work done so far. With all the changes I'd like to make I'm told I cant use my pick of contractors nor can i talk to the contractors also my say so means nothing. Like when I told the builders I did not want control joints cut in the slab over a week after pouring. So the builder told his concrete guy to go cut them before I found out.
 

Garrett Foster

Garrett
Joined
Jun 8, 2019
Messages
30
Location
Oklahoma
Garrett, I hope that you take the bull by the horns in this situation before you start framing. It is bad enough what we see when there are permits and inspections, when there are no permits or inspections, I could only imagine how lackadaisical construction may be. Good luck. You really need to slow this down and make sure it is all done to the state code regardless of whether or not there is a permit.
I'm trying to find the right routes to get a state inspector to make sure these guys dont screw me. However all I have found are engineers charging $650 for an assessment. Which I dont know if that will even help.
 

ICE

Moderator
Joined
Jun 23, 2011
Messages
9,344
Location
California concrete jungle
Every two story house that I have been involved with had an engineered set of plans. The cracks appear to be shrinkage cracks. I am not familiar with Xypex but I did watch an application video. I don't think that it is a viable solution in your case. I would recommend Redgard. You stated that you have a bid of $7000.00 for some method of crack repair. That seems too costly for what you need.
 
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