43
votes
Is this cracking foundation under a jack post a problem that requires repair?
I'm not familiar with USA house construction methods (I live in the UK) but speaking as a mechanical engineer, I wouldn't even stand near that thing while debating how safe it was.
That bolt is ...
- 894
32
votes
Accepted
How do I self-repair a section of crumbling basement wall, or should I hire a professional?
It looks like a cosmetic DIY patch-job was already attempted before. The current situation is exactly how you can expect your attempt to turn out.
This is a structural issue and I would hire a ...
- 16k
27
votes
Accepted
Why did cracks form over the rebar grid in my concrete footings?
This is known as "plastic settlement cracking", a type of shrinkage crack. It's the result of the rebar being too close to the surface. As water settles out of the concrete, it tends to ...
- 126k
24
votes
Is this cracking foundation under a jack post a problem that requires repair?
This should make the hairs on your neck stand-up. What my first thought was is the sand fill that the concrete was floated on has been undermined. Is there a sump pump well in the basement? And if so, ...
- 10.9k
23
votes
Accepted
What to do with sprinkler pipe under spiral staircase foundation?
Dig the hole bigger.
Buy four elbows, some pipe clamps and some extra pipe.
Turn off the water for that pipe.
Cut the pipe and with the elbows have it go around the box.
Make your footing and no ...
- 21.9k
19
votes
Can a power transformer cause building vibration
You mention the vibration happens more often when it's cold. It could be related to the building's heating system or, perhaps, the outdoor unit of a HVAC system with an old or imbalanced fan.
- 1,012
18
votes
Accepted
Contrator made Concrete parallelogram for shed foundation
I am not going to get into payment/ legality/ recovery discussion. Obviously the guy messed up and you will have to deal with that as best you can.
Removal and redoing the slab would certainly be ...
- 4,523
17
votes
Can I pour a concrete foundation in multiple pieces?
Yes, you can do that. Provide plenty of rebar length past the joint. The vast majority of commercial projects are poured in sections, and virtually everything more than 60-70 years old was poured in ...
- 191k
15
votes
Accepted
Does this water tunnel for rain look ok?
Without some sort of retention, that trench will likely cave in or mud up.
Using the existing trench, you can improve it with a bit of effort:
Dig the trench a bit deeper and lay some "big-o"...
- 15.7k
14
votes
Accepted
Can I pour a concrete foundation in multiple pieces?
I agree with Ecnerwal, yes you can do that. I also agree to extend the rebar past the pour (drill holes in the form boards and extend the rebar out the holes).
Code (and CSI) require 30 bar diameters. ...
- 3,728
14
votes
Does this water tunnel for rain look ok?
Call me old fashioned but there is a downspout which you can extend to your destination.
- 16k
13
votes
Is this cracking foundation under a jack post a problem that requires repair?
Definitely get a home inspector to look over tbe place; there may be other damage from this subsidence...
If the price is attractive enough that you'd consider trying to have this redone properly, I'...
- 25.4k
12
votes
Accepted
In a house fire, how hot does the foundation have to get before it too has to be replaced?
The information is incorrect, the temperature at which concrete becomes unsafe for re-use is significantly lower, 570 degrees F actually. The 'telltale" sign is if concrete that was not charred from ...
- 14.8k
12
votes
Accepted
Can this water damage be explained by lack of gutters and grading issues?
You've really got a two-step question here
Would a lack of gutters and grading explain the water?
The simple answer is yes. That's the source here.
Even without gutters and proper grading, should ...
- 23.4k
12
votes
Accepted
Can I run an underground wire to a shed on blocks?
Yes, the national electric code allows wiring in structures like your shed.
If you plan on using UF wire for the run buried 24” deep you need to bring the wire up in conduit so the wire is protected.
...
- 102k
12
votes
Why did cracks form over the rebar grid in my concrete footings?
Potentially there are three issues. The cracks could be caused by any single issue or any mix of the issues.
Not enough clear cover over the rebar mat.
The concrete mix contained too much water (...
- 3,362
11
votes
Can I run an underground wire to a shed on blocks?
It is advisable to use a slip joint [expansion coupling] on the conduit stub up, otherwise nothing out of the ordinary. Around here, that's not out of the ordinary even with a poured foundation.
...
- 191k
10
votes
Accepted
What are my options for saving this building?
Ultimately, I decided to save it. I used stacks of cribbing with large beams to jack the building up off of the failing foundation walls. Similar to this (much larger) example:
Once I had it up on ...
- 587
10
votes
Accepted
Is it common for residential foundations from the 1960s to contain asbestos?
For concrete foundations no, asbestos is not an issue. However, the earth in your location may contain asbestos. In Northern California my brother is having a pool installed and they had to monitor ...
- 102k
10
votes
Leaving basement forms on permanently
Sounds like a hack-job approach to me.
That wall could be built from concrete blocks (aka CMUs or concrete masonry units), with bond-block rows and reinforcing steel, and grouted full, making it ...
- 191k
10
votes
How do I self-repair a section of crumbling basement wall, or should I hire a professional?
The first step of repairing a deteriorated wall is to knock loose and remove the bad materials to the solid base. However, in your case, I suspect there is nothing solid that remains, as the cracks ...
- 3,362
10
votes
What to do with sprinkler pipe under spiral staircase foundation?
A pipe rupture beneath the foundation could cause soil subsidence that will destroy your staircase. For that reason I would now route the pipe far from the staircase. Cut it inside the hole you dug, ...
- 31.8k
9
votes
Is this cracking foundation under a jack post a problem that requires repair?
If your gut is telling you to run then run. But if you are still thinking about purchasing the house I would make sure that the builder gives you something in writing to back up what he/she is saying. ...
- 988
9
votes
Accepted
Should I repair or replace floor joists with holes in poor locations?
None of the holes are an issue.
There is some slight compression with the one joist - in your top picture. But it doesn't look to be an issue and it is certainly not caused by that small hole. If ...
- 47.7k
9
votes
Why are basement walls subject to tensile forces?
All walls experience tensile stress. This is not a force trying to pull the wall apart as such. The stress comes from lateral forces that can arise from two sources.
Firstly, a simple lateral force ...
- 1,294
9
votes
Accepted
What's the intended purpose for these rebar protrusions?
Those pieces of steel are not rebar, they are form ties that are used by the foundation people to rigidly hold the inner forms and outer forms at a fixed distance. They are held in place during form ...
- 9,806
9
votes
Concrete base for parcel box
Size will be an opinion mainly, but at least 5 to 8 cm(WxL) bigger than the box and about 8cm deep/thick.
Anchor bolts should be easy to use to anchor the box and will make the box easy to remove for ...
- 21.9k
7
votes
Accepted
Will the concrete slab in a partially heated shed conduct a lot of heat to the unconditioned area?
I'd have no concerns about doing what you describe. I've seen it done many times here in frigid Minnesota. Build your walls (using treated lumber and suitable nails where it contacts the slab), ...
- 126k
7
votes
Concrete base for parcel box
The depth depends on your regional frost line. For europe we have 80-150cm (varies wildly per source, depends on your location) frost line. That means, to avoid frost-heave, the textbook says the ...
- 2,501
7
votes
Accepted
Is this crack a sign of foundation problems?
Most houses move a bit. Unless you have some kind of sudden catastrophic fail, which is extremely rare, then really the trouble with foundation slippage or subsidence is it's usually so slow you can't ...
- 9,265
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