Concrete is composed of cement, aggregate (including crushed rock and sand) and water. In homes, it's frequently seen in the foundation, driveway, sidewalk, patio, and stone walls. Note that bricks use mortar in the joints, not concrete.

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How to add on to a concrete patio?

I would like to add on to my existing concrete patio with more concrete. I will about double the size of the patio. My question is, should I have the new patio free floating from the existing or ...
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Are cracks in a newly poured concrete basement floor a problem?

I'm having a new home built and found a large crack in the newly poured concrete basement floor and wanted to see if it's something I should be concerned about. The floor was poured sometime in the ...
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Why do builders say that wet concrete/mortar is not as strong?

I have been watching a few videos demonstrating the mixing of mortar and cement and a constant theme is that you must not have the mix too runny. I cannot fathom the reason... Does anyone care to ...
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651 views

Is it OK to pave without mixing?

Going upon the advice of a reputable builder, I used Quikrete fast-drying concrete for a small slab outside my house. Not load bearing. His recommendation was to dry-pour the whole thing. Framed, ...
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992 views

How can I pour a concrete pad with a circular hole in it?

Essentially, I'd like to put down a concrete pad for a patio, but leave a couple of circular areas within that patio unpaved (for planting shrubs). I'm familiar with the techniques for using ...
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re-using wood from a concrete form?

I strive to not waste materials wherever possible, and "use once then discard" methods are particularily irksome. So with this mind, what suggestions do you have for enabling re-use of lumber used for ...
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How do I fill in around waste pipes?

Broke the concrete in my basement to run new pipes for the basement bathroom. The plumber put sand under the pipes to support them at the correct angle. I asked him not to glue the vertical sections ...
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4answers
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Do I have to remove the old thinset before installing new tile?

I will be installing some new 12x12 tiles in two bathrooms approx 25 sq/ft each. When I pulled up the old tiles, there was no thin set that had made contact with them so the removal was very easy. ...
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How do you secure wood framing to a concrete basement floor?

I'm using Pressure treated lumber for the bottom plate in a basement finishing project. What should I use to seperate the wood from the concrete? What are ways to secure the bottom plate to the ...
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Driveway expansion joints are rotting wood: What to replace the wood?

My driveway was poured in sections with lengths of 2x4 which remained between the slabs as expansion joints. Due to heaving and moisture many of these are in poor shape. I replaced one once by ...
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How can I level my basement floor, which has a 4-inch dip?

I googled today on how to level a basement floor. Most people recommend using SLC (self leveling concrete)... I don't think I can just use that because of the pitch of my floor (and from what I hear, ...
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Should gloves be worn when working with concrete to prevent it from coming in contact with skin?

I was told recently that concrete is slightly corrosive. Should gloves be worn when using concrete or is it fine to handle concrete as long as its not done on a regular basis?
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How do I build a form and pour a concrete pad?

I have a new safe that I want to put out in the garage. I'd like for it to be in a specific corner, but that corner has a few quirks. First, the slab is pretensioned. No cutting, drilling, coring, ...
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How can I color concrete?

I'm going to be using a mold to pour a concrete pathway and I was wondering about coloring options. I've done this previously with this quikrete product. It worked and turned out okay, but one bottle ...
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3answers
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How do I remove THIN layer of carpet glue from concrete?

The folks who owned this house before us were the cheapest people around. They glued carpet to our concrete floor with a very thin layer of glue. Now, I'm having a terrible time scraping it off. I ...
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427 views

How can I get the 2-part epoxy smell out of concrete?

Six months ago or more, my friend used a 2-part epoxy (no longer have the packaging, but it's a double-syringe with clear liquids, purchased at Home Hardware) on something, and some of it (one or both ...
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2answers
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Can old concrete fragments be cleaned and used as crushed stone?

Suppose I need to replace old concrete on a driveway or in any similar scenario. The usual way is to just gather all the old concrete and dispose it to a landfill, then buy cement, sand and crushed ...
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How can I make these concrete columns?

I want to make a narrow concrete, decorative column like the ones found in this garden.. What is used as a mold for these types of columns? What gives the concrete those subtle color changes (the ...
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How can I hang a large but light poster on a concrete pillar?

I have a large (est. 5'x7') sheet of plastic foam with a poster printed on it. It weighs maybe 3 lb and is reasonably stiff. I'd like to hang it on a solid rectangular concrete pillar about 2' wide. ...
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627 views

What are “concretors' nippers” for?

I came across this tool called "concretors' nippers" I guess they are for some operations with concrete reinforcement, but can't find any details. What operations is this tool for specifically? ...
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Does 100 yr old concrete floor need replacing?

Our house was built in 1905 and the concrete floor is uneven and gets a lot of moisture at times. We replaced the gutters which helped a little. We'd like to finish the basement, maybe use stained ...
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How do I know when concrete needs replacing rather than just mud-jacking?

I have a concrete driveway and path to my front door. Much of it has become unlevel and I'm contemplating having it mud-jacked. However, before I do, I wanted to know how I could easily tell when a ...
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How can I prepare uneven concrete basement floor for vinyl planks?

I have roughly 600 sq ft of basement that needs new flooring after some unfortunate flooding this past summer. We had carpet over concrete and are now looking to lay vinyl planks down. There is about ...
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Is it safe to drill small holes in load-bearing concrete beams for expansion bolts?

It seems to be very common to drill small holes in any kind of structural concrete for mounting fixtures without worrying too much about any kind of reduction in strength of the structure, but I ...
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What drainage should I install under concrete slab in garage?

I have a concrete garage which is halfway inside the hill. Essentially the surface behind the garage is at garage's roof level. Garage's floor is concrete slab 3"-4" thick (at least it's best I could ...
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Do I really need to use primer when painting an unfinished concrete floor?

I'm turning a one car garage into an office and want to paint the floor. I bought some Behr concrete paint, and the guy at Home Depot insisted that I have to put down a layer of primer first. Do I ...
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633 views

How to connect wood to concrete

How can I attach wood to concrete in this bench?
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Is it possible to patch concrete stairs?

At my church, there is an old set of stairs made of concrete. They've begun to crumble on the top to the point where the treads are no longer flat and smooth. I've not seen any material that has ...
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Would wrapping a wood fence post in plastic help protect it?

I'm geting ready to install a couple new wooden privacy fence gates on the sides of our house. One of my co-workers suggested to wrap the 4"x4" with plastic stretch wrap around the 2' part that will ...
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Can I hang a heavy weight from a concrete ceiling if I reinforce it with fiberglass?

I'm investigating the possibility of hanging a pull-up bar/ rock-climbing training board from the concrete ceiling in my apartment. The slab is 180mm (7inches) thick and the (static) weight which I ...
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5answers
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Do they make a non-liquid concrete/mortar color additive?

I've been trying to find a cement additive to change the color of some mortar, but only seem to be able to find it in liquid form at my local big-box hardware store. I'm looking for a similar ...
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Can I build a deck this low to the ground?

I want to build a deck off the back of my house. The door is near grade level, about 1' above. The grade doesn't have very large slope, so that means that the beam at the far end would be below grade: ...
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How to finish room with protruding concrete ledge/foundation?

I am finishing a basement room and have a concrete ledge which is part of the foundation. It protrudes into the room about 2.5 inches and is about 6 inches high. This ledge is the result of a ...
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Best way to tear up half a concrete parking pad?

I have a concrete parking pad in my back yard (butts up to an alley) that is substantially larger than I need, and I'd like to reclaim some of that space for my yard. To that end I'd like to tear up ...
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How do I drywall over a partial cement wall?

I have 9' walls and the bottom foot or so is cement on one wall. What's the best method to drywall over this wall so no moisture seeps in? As you can see, there was moisture seeping in down at the ...
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Drilling holes in concrete

I'm not what you'd call a handy guy, and now wife wants me to put up curtains. This task is reduced primarily to getting a bit of metal stuck to the ceiling. I bought screws and anchors. The anchors ...
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6answers
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How do I hang shelves on poor quality brick/concrete walls?

I'm trying to install some shelves in my apartment (brick/concrete) but when I drill holes the walls almost seem like they're made of sand. I'm not able to securely fix the screws (I'm using wall ...
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2answers
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How can I stop mortar plugs from popping out of slab holes?

Our termite people plugged their dozens of chemical insertion holes using a regular grout. Needless to say the plugs are popping out left and right. (They tell me that is normal, the plugs pop out in ...
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How do I seal a large gap between slabs to avoid freeze/thaw heaving?

I have a very large slab patio on the back of my home in Southern MN that has pulled away from the house about 6-8" due to freeze/thaw heaving. The previous owners have filled the gap with river ...
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How do I fill a hole under a sidewalk?

The sidewalk leading up to my front door developed what looked like a sink hole under it about a year ago. Since then, an animal of some kind has made the hole even bigger and it now runs as a tunnel ...
6
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1answer
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What should I do about my concrete shower curb that I did not remove all the air bubbles from?

I'm building a concrete shower curb and pan. I built the curb and when I removed the 2x8 forms I notice that I didn't pack the cement all the way to the bottom in some parts: A bit crumbled and ...
6
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1answer
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How do I prepare an interior cement floor for painting?

I have an enclosed carport that serves as 4th bedroom/den in a 30 year old house. This room has long been used as storage, etc, and is in fairly bad shape. I'm rehabbing it to serve as a home office, ...
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2answers
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What can I do about this gap between my driveway and the street?

I have a low car and the ditch between my driveway and the street is pretty big. I usually enter my car in reverse at a very steep angle as to not have it scrape the lower front. My neighbors park ...
6
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2answers
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Is it normal to find cracks in new concrete?

I'm having a house built and they just completed pouring the slab for the foundation a few days ago. When I inspected it today I noticed several narrow (but sometimes long; one or two do them appear ...
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2answers
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What should I consider when cutting/making window in concrete foundation?

I am thinking about putting in another window for my basement apartment. I would like to know what do I need to consider before trying to find a contractor to do this. I have uploaded a picture of ...
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2answers
702 views

How can I strip and repaint a concrete porch?

My porch is concrete and has been painted over several times, the last time by the previous owner using paint that is obviously not appropriate (it's very slick when it rains/snows). It needs to be ...
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Pouring a concrete slab against my house: how to frame it up against the outside wall?

I have a concrete front stoop that drains some water into the basement, so I am going to knock it out and pour a new slab with better grading. The slab will be about 4 feet square, and fits into a ...
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1answer
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How to stop outside rainwater from coming in under the wall and through the concrete floor of my garage conversion?

I have got a problem with an attached garage converted den in a 1978 built brick home. The heavy spring rains are redirected to the two year old perforated drain system on the side of the house ...
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2answers
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What should I do about a crack in the concrete slab in my living room?

We purchased the house about 2 years ago. The house is about 50 years old. Today we removed the carpet and the hardwood floors under the carpet. We found out the slab has an approximately 10ft long ...
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How do I secure a canvas garage?

I picked up one of those cheap canvas garages from Costco, to keep a few things out of the weather. It's 10' wide, 20' long, and maybe 11' high at the peak. Our area is a bit prone to windstorms. I'm ...