50

Lay the steel plate on the concrete where you want it. Draw a line around it. Cut a piece of paper to the same size as the steel plate. Place it on the concrete in the same position as the marked outline. Locate the concrete holes by gently pressing down where you think they are (tracing paper makes this even easier). Poke a hole through the paper at ...


43

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 presumably supposed to be fixing the post against it popping out sideways. I suppose it was meant to be bolted to a metal beam underneath the concrete. So either ...


31

By way of example, the pink Owens-Corning FOAMULAR 250 product and the blue DOW STYROFOAM Brand SM product rated for 25 and 30 psi compressive strength respectively. If weight is distributed and applied evenly a square foot of FOAMULAR 250 could support 25*12*12=3600 pounds at its limit while the STYROFOAM could support 4320 pounds. A footnote in the data ...


27

Unless your home is a 20 bedroom mansion I would simply tell them to keep that off your driveway period. You can't tell what load it will take because it depends how packed it still is, what condition it is in and how thick it was poured (and if this was uniformly done). Often these large trucks will crack driveways in the corners of their pours since ...


24

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, do you live in an area that gets a lot of rain? Also, what's missing from that photo ( that hasn't been installed) is a concrete footing of some sort to ...


21

My only guess is that a watery mix will have the layers settle in their different sedimentary layers with the fine cement settling to the bottom... One reason is that the aggregate can settle to the bottom much too easily, yes. This is called segregation and results in non-cohesiveness of concrete. Another reason too much water is bad is that it can ...


21

The simple way to "achieve that shape" is, of course, to buy it precast, which is almost certainly what the picture is - depending on size, it's either a section of well-casing, drainage pipe, or a manhole extension. @BrownRedHawk is correct that it may (indeed, probably will) destructively deteriorate if used as direct fire containment - the interior ...


20

Like Greebo says, you want to get back down to the concrete, but I'd suggest that more to have a flat surface to build on top of. To make the job go faster, you can use a power tool. Several would get the job done: Power Chisel (best fit for the job): Air Hammer (you'd need a high capacity air compressor): Demo Hammer (more power than you need, but it ...


20

Concrete is a mix of large aggregate, small aggregate, and cement (a 4:2:1 ratio is a good approximation - though designed mixes will be more calculated than that). The size of the large aggregate isn't particularly important, unless you are working in very tight spaces or around reinforcement, in which case you want suitably small aggregate. In this case ...


19

While you probably could, this wouldn't be a good way to try and match a color. It would likely effect the setting performance of the concrete and you'd never match the color of the paint. On top of everything else, it would be much more expensive than the alternatives - all you really need is the pigment and everything else that makes up the paint is ...


18

The tile floor shouldn't be a structural weakness, but if it's glazed you won't get a good mortar bond. I'd install anchor bolts every 32" or so, aligned with block cores, and fill those cores with mortar. It might be easier to simply cut the tile inside the wall line and remove it, though. Also be aware that your slab may not be designed to carry a ...


16

Well this is a pretty big deal because we don't know the cause. First let's go over common reasons we get cracks on new floors. Soil wasn't properly compacted. Soil should be compacted with a rock bed on top. Bad mixing at site. Especially in the summer contractors pump too much water in the mix. The water makes the concrete weaker and it does crack ...


16

The item you have pictured appears to be a precast fire ring. Several companies manufacture them specifically for fire pits. Depending on pricing and availability, it might be a lot easier, and possibly even cheaper to purchase one instead of trying to create your own. Since these are specially made for the purpose of being a fire pit, the manufacturers ...


16

You need to slow down and rethink this. You are on the verge of making a couple of serious mistakes. Rather than directly answer your question, I am going to advise a plan to do this correctly. First, you should not pour concrete around wood support posts. This is a good way to invite rot and an unstable support system. The floors should be jacked up a bit ...


15

Having done this exact thing recently, I found that using the hard metal brush attachment for the angle grinder worked very well to remove thinset without affecting the concrete beneath it. I'd lean towards the stiffer bristles. Be sure to wet the thinset before starting, and as needed. The thinset comes off like mud, leaving clean concrete. Once finished, ...


15

My suggestion is to add to the size of the concrete drive way in the following manner: This gives you the option of backing up out of the car port in the new area toward the rear yard. Then you can drive in a forward direction which would be far easier to navigate by the truck and the corner of the house. Additionally the part added onto the side nearer ...


15

The usual methods are: Careful measurement. Really this doesn't need to be that precise, you are not looking for a press-fit between bolts and clearance holes. If it goes wrong, just elongate a hole into a slot using whatever tools you have to hand (e.g. a round file, clapped-out old Bridgeport, ...) - Remember: "A grinder file/filler and paint make me ...


14

I would be tempted to try those removable stick up hangers from 3M. They come in different sizes for different weights. They don't penetrate or leave a stain when you remove them.


14

Great question. Adding this addition requires a really good, deep, compacted base. I would isolate it from the building by 1/2 inch, but if the base is good, rebar to the existing pad will help stop any displacement. You have to expect some settling, but the better the base, the smaller the amount. Web rebar won't help much, but 3/8 or 1/2 inch bar will hold ...


14

No. Unless you live in a swamp, there won't be enough moisture, and even if you do it won't be mixed with the cement properly. The concrete will be dry, crumbly, and have no strength. Just mix it like the directions say.


13

Probably yes. And probably an oil based primer unless the can says otherwise. On top of that a concrete primer if they exist. If you don't prime then you run the risk of the paint peeling, especially since garage floors are so smooth. Plus you might run through way more paint than you think and need to get more since concrete is so porous, it will soak ...


13

I'll assume that the hole is there because concrete was put onto unrammed gravel. The current state is left on the picture Now assuming you've got rid of the animals you have to stabilize the existing concrete and the gravel beneath it. The easiest way would be to excavate some of the gravel until you reach some stable foundation (I'd guess it's around one ...


13

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'd suggest getting an engineer who know the local soil and hydrology to look at it and tell you what it'd cost to redo this properly. Better to spend a few ...


13

Any information you'd glean from this discussion is untrustworthy for the following reasons: No photos. They often reveal issues not mentioned in your short description. No dimensions. In engineering, dimensions are key. No information about construction era or age. That would tell us a lot about common building techniques. No liability. Anyone telling ...


13

With the epoxies I have used minor imperfections like small divots from a heavy object chipping the floor are usually filled in. The epoxy can make a very slick surface. For instance, I coated one bay of my shop that I do automotive work in and wanted it like glass so oil spills were easier to clean. This worked great until I spilled some antifreeze. The ...


13

Shouldn't be a problem at all - look in your local hardware store for masonry bits and concrete wall anchors.


13

This slab is small enough that you should be able to easily lift it out and repair the base soil. Unless the concrete was weak initially or in otherwise poor condition it won't break. From the lawn side, trench along the slab about 6" wide and to the bottom of the concrete. Save the sod by wrapping it in a tarp. Using heavy steel or wood bars and some ...


12

It's all about particle size, which is classified using the Wentworth scale or The Krumbein phi (φ) scale. Sharp Sand Sharp Sand, also known as Concrete Sand is a coarse sand with larger particles. This type of sand is typically used in concrete. φ scale - 1 to 0 Size range - 1/2 to 1 mm (0.020–0.039 in) Builder's Sand Builder's Sand, also known as ...


12

Yes you can remove them. They are not a complete unit anymore. There was a wire extending from the center of the square disk, you will still see the nib that held the wire. The purpose of the wire was to push one type of insulation or another over it. The insulation was held in place by another disk that grabbed the wire and it would not allow the insulation ...


12

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 nearby combustibles turns a pinkish hue. That color change is due to chemical changes in the iron-containing compounds in the aggregates used in making concrete ...


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