18
votes
Accepted
Why are there holes drilled through a basement slab near exterior walls about 18” apart?
The holes are an indication of drilling through the slab to inject termiticide as a treatment for subterranean termites.
This is common in slab homes in the southeast of the United States.
Plugs are ...
- 42.8k
16
votes
Accepted
Are loose-stacked bricks a suitable base for concrete steps?
The bricks are very dense and make a good fill.
Not having the steps covered does not make them structural. Structural is something that supports something else.
If you don't want the bricks to be ...
- 42.8k
13
votes
My bathroom slab is 2 inches lower than the rest of the home's slab. How should I level it?
What a great opportunity to do a slightly sunken walk in shower so you don’t need to have any curbs or whatever. Drop a claw foot on top that drains to the floor? Very cool.
Definitely go with a ...
- 131
13
votes
Pouring a concrete slab in batches
A 7x9 slab is not very big...unless you are buying bags of concrete mix, loading them in your vehicle, unloading them to the site of the work, mixing them with water from a hose, pouring out of a ...
- 42.8k
12
votes
Accepted
Increase Thickness of Concrete Pad (for BBQ Island)
I would drill a few/bunch of holes in the old concrete and fill with short steel rods/rebar/bolts as anchors. About two inches above the old level, and in about two inches in the old concrete.
Fill ...
- 30.3k
8
votes
Accepted
My bathroom slab is 2 inches lower than the rest of the home's slab. How should I level it?
I would suggest using concrete and leave enough depth for expected tile work.
Per https://www.cement.org/docs/default-source/fc_concrete_technology/is144-07t-resurfacing-concrete-floors.pdf
The ...
- 16.9k
8
votes
My bathroom slab is 2 inches lower than the rest of the home's slab. How should I level it?
The old homes built from the 40s to and early 60s used concrete as the base for a tile floor. The usual rule was a minimum of 2 inches.
This is why the floor is 2 inches lower after you removed the ...
- 42.8k
8
votes
Increase Thickness of Concrete Pad (for BBQ Island)
There's no need to raise it that much.
Put on ~1/2" of thinset, with proper slope for drainage (so, not 1/2" evenly, if it puddles now. Slope at 1/8" per foot towards the edges so water ...
- 226k
8
votes
Pouring a concrete slab in batches
Yes, you can do that. You have to provide something like rebar between the sections to tie then together, and maybe some expansion joint material. Heck, they pour road beds like that all the time. ...
- 7,022
7
votes
Accepted
Is it safe to excavate soil next to concrete slab?
The only issue would be if the regrade created a soil erosion problem that eventually removed soil from below the slab. As long as the compacted soil stays below the slab, you're fine. Assuming that ...
- 10.6k
6
votes
Accepted
Concrete bags vs truck for slab
You should get a batch mix for this so that you can continuous pour it from end to end in a short period of time. This is the best way to assure a uniformity and even drying time for the whole slab. ...
- 66.5k
6
votes
Accepted
How much should I worry about this large crack in the foundation slab?
Sigh. Cheap builders are forever spending thousands on concrete, but unwilling to spend a few hundred on steel to make the concrete properly reenforced. Nobody sees the steel, but the lack of it does ...
- 226k
6
votes
How can I pour a 20' x 20 ' slab on a slope?
Assuming you're planning to DIY, be ready for it to be a lot of work.
The primary method to place concrete on a slope without having it all end up on the bottom is to use "low-slump" ...
- 226k
5
votes
Accepted
Is there enough time to pour 40 sqf 4" slab with 60lb bags of premixed concrete if working alone? Any hints?
The answer depends on your level of physical ability and ambition, and is therefore mostly subjective. There are plenty of folks who could do it. I wouldn't try it myself at my age and level of ...
- 149k
5
votes
Is this crack something that my builder should fix?
That crack is typical of concrete. There is just minor separation with no shifting along the 2 sections.
The groove formed in the adjoining surface is a "control joint". It is there to ...
- 37.4k
5
votes
Pouring a concrete slab in batches
Addendum to SteveSh's answer...
You want to form the sections separately by running a board across at the point where you'll stop the section. The form board at that point can be shorter in height ...
- 149k
5
votes
concrete slab for shed base
2" concrete is not a good idea. 4" is the usual standard. That calculates to:
80 cubic feet
3 cubic yards
133 80 lb. bags
Plus you need a base under it (not sure what's best - I see a ...
4
votes
Accepted
Should I form and pour the concrete all at once?
If you don't care about leaks (or want drainage, so the dog is drier) forming the rim, pouring the rim, and then pouring the central slab is similar to whats typically done in a house basement. The ...
- 226k
4
votes
Accepted
How best to repair 24 sqft dirt hole in concrete slab
Probably low-stress, may not need anything much, but in the "better safe than sorry" mode I'd drill half-inch holes around the edges and stick reinforcing rod into them anyway. Steel is cheap compared ...
- 226k
4
votes
Is there enough time to pour 40 sqf 4" slab with 60lb bags of premixed concrete if working alone? Any hints?
You want to pour a slab of 40 square feet (so something like 5 by 8) and four inches thick. Let's break it down with numbers:
I'm imagining about 1 bag per square foot, so you want approximately 40 ...
- 666
4
votes
Accepted
What to use as a screed edge along a brick wall?
The conventional way to handle this problem is to use a length of 1.5 or 2 inch diameter pipe as the screed reference level. This pipe sits on top of a series of stakes that you place in the ground in ...
- 66.5k
4
votes
Can the vapor barrier between a dry floating concrete slab and linoleum flooring be foregone?
Insulated slabs usually have vapor barrier underneath. Since you did a test and found no moisture, there should be no problem installing vinyl flooring on it.
- 149k
4
votes
Does laminate flooring need an independent vapor barrier on concrete?
Lots of slabs are covered in carpet without any problem. It depends on your specific slab. To know you need to test the slab. Take a trash bag tape it down to the floor. In 24 hours pull it up. If the ...
- 103k
4
votes
Can I put a 32” x 60” curbless shower in a post tension slab?
The problem with a post-tension slab is that you, at this point, don't know where the tensioning bars/cables are nor do you know what parts of the slab are "structural".
Even if you can find ...
- 23.5k
4
votes
How can I pour a 20' x 20 ' slab on a slope?
You want a decent bedding below that slab anyway. Dig and fill that so it's level. Build the retaining form you'll pour the concrete into so it's at least close to level, perhaps with a slight slope ...
- 33.2k
4
votes
Will I have condensation on a slab cooled with groundwater?
Hint - what's the dewpoint in cooling season? is it below 55°F or above that? Dry desert you might not drip, as the dewpoint might be below 50°F all summer; where it gets hot and muggy with dewpoints ...
- 226k
4
votes
Accepted
concrete slab for shed base
If you're buying bags of gravel and concrete mix, you'll find that they are around the same price. Gravel may even be a little more expensive than the equivalent weight of concrete mix. There's no ...
- 12.8k
3
votes
Accepted
DIY poly-jacking?
I suspect Tyson is right about the old holes being from termite treatment (although they should be 1' apart for that, so it would have been a crappy, ineffective treatment job). If they were from ...
- 6,198
3
votes
How to repair concrete damage from pulling up nail strips
Those small dimples are unlikely to ever be a problem, but if you want peace of mind, get some vinyl concrete repair patch material and skim it on with a wide putty knife or trowel.
- 149k
3
votes
Is gravel required under a concrete slab under a building?
Summary: No, gravel is not mandatory in all cases; but it can be very important in others. It depends what you need: gravel can provide a capillary break (preventing water from wicking upwards), can ...
- 5,635
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