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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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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3answers
7k views

Extending concrete Slab

I have a 10 x 10 slab (4 inches thick) that is already in my back yard in the corner. I bought a kit to build a 10 x 10 shed on it, and then realized that would put it right up to my fence. So my ...
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3answers
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How do I hang a chair from a concrete ceiling from a single hook?

I'm putting in a "hanging chair" in the basement and it's supposed to hang from a single hook in the ceiling. The ceiling is reinforced concrete. Now, I'm about 125 kilograms (275 lbs) so I reckon ...
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8answers
30k views

What is the best way to remove and prevent leaf stains on concrete pavers?

We have a brand new paver stone walkway/patio. To my dismay, I noticed that their were leaf and acorn stains from the oak tree in the front yard. I've learned my lesson and I'm going to try to keep ...
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2answers
157 views

What's the proper way to fill this hole?

Recently a dip formed in our flooring inside our sports performance training facility. We discovered that the concrete job there had a good number of stones in it, and I believe that it was that ...
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10answers
70k views

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. Now,...
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1answer
5k views

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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6answers
33k views

How to remove construction adhesive from concrete?

We removed a wooden dance floor that was glued to concrete with liquid nails. How do I remove the liquid nails that is all over the concrete floor? Has anyone had success with heat, mineral spirits ...
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1answer
263 views

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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2answers
1k views

How to repair cracks in concrete overhang over entrance

I have a slab of concrete over the front entrance of my house with some serious cracks in it. I don't actually know what the proper name for it is, which makes this difficult to Google - so I've ...
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1answer
534 views

Installing a strong-tie post anchor on unlevel concrete

I'm building a short (3.5 ft) fence in my front yard. I have most of the posts sunk in dirt holes, but two of them will need to be mounted on a concrete slab. The problem is that the slab has a ...
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2answers
1k views

Building on top of 3/4'' plywood subfloor

I want to build this: http://www.mrmoneymustache.com/2012/12/21/how-to-make-a-relatively-sweet-shower-cheap/ and I'm building in my basement bathroom: on top of the foundation I have 2x4 (horizontal) ...
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1answer
58 views

What type of substrate should I use to install pavers over an existing poured slab patio

I'm going to be putting pavers over an old slab patio. The current patio has settled and spalled, so I'm looking to pitch the paver patio in such a way that it drains as the original slabs did. In ...
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3answers
24k views

How to mount hooks into concrete ceiling that must be able to support several times bodyweight?

I am on the top floor of a loft apartment that used to be a factory. I want to install several hooks or some other fixture into my concrete ceiling from which I can hang gymnastic rings, a punching ...
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7answers
42k views

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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4answers
9k views

What is the best way to remove pet odor from concrete?

The concrete floor in my garage had been home to a large dog for several years. There is a visible stain and strong smell in one area of the garage floor. The concrete does not appear to be sealed ...
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1answer
1k views

What is involved in enlarging a concrete garage door opening?

I have a concrete garage with an opening measuring 99" wide by 85" high. There is 10" of concrete from the door opening to the left and right walls and about 1' above. All walls are 8" thick and ...
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2answers
2k views

Concrete slab at a brick wall

I want to build a concrete slab (upon which a deck will be build later) at the foot of a brick wall (by foot I don't mean the foundation foot, I just mean where the brick meets the grade level). I ...
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4answers
6k views

Can I mix latex paint into concrete

would like to color concrete mix can I use outdoor latex paint to mix in with the concrete?
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3answers
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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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2answers
12k views

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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4answers
1k views

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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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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2answers
7k views

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
4k views

When would I use epoxy anchors?

Epoxy anchor is essentially a metal alloy rod set onto epoxy. A hole is drilled and cleaned, then epoxy is put into the hole and the rod is inserted into the hole and left until epoxy sets. Using ...
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3answers
819 views

How will concrete fill in?

So I am pouring some footings for a deck I am building and my current plan is to dig a hole that is 18" wide and 18" deep. I'm then going to suspend a sonotube about 6 inches above the bottom (using ...
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2answers
4k views

Building a raised wall for a pond

We are looking to build a small pond (9'x18'x6'), but we want the edge to be raised up about 8". I am thinking about using CMUs (Concrete Masonry Units) which are 8x8x16. The entire pond will be lined ...
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1answer
155 views

Can I rest cement posts directly on the bedrock to build a structure for a large shed?

So I live in Canada, where winters are cold, and where there's not much soil above the bedrock. I would like to build a sturdy structure for an existing "shed" (in fact a 100-year old former stable or ...
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1answer
5k views

How wide does a 6x6 concrete post footing needs to be?

Need to attach 6x6x8 posts for a free-standing pergola - I'll use Strong-Tie anchors attached to the concrete footing. The hole for the footing will reach well below the freezing line, but how wide ...
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1answer
942 views

How do I flatten my uneven concrete floor?

We have an old Victorian house with a concrete floor throughout the ground floor. The ground floor is partitioned in two by a dividing wall and french doors. From the front of the house to the doors,...
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2answers
525 views

How should I waterproof a concrete roof?

We have a 28y/o Medical Clinic in a remote area of Haiti. The roof is concrete and has one coat of DryLoc on it which is lifting off in many areas. The roof is 136' X 35' with a very slight pitch to ...
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2answers
178 views

Should cement be placed under concrete slabs for driveways or is sand enough?

I am about to get my driveway full slabbed using normal concrete slabs like below (i will be using rectangle slabs as opposed to square). The builders that came to give me an estimate said it would ...
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2answers
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How can I replace laminate with polished concrete flooring?

I'd like to investigate whether I can replace my first-level flooring - currently faux-wood laminate - with polished concrete. What do I need to know? Is it even practical to put down polished ...
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2answers
2k views

How can I remove a parking block from my garage?

So, builders have this thing, for some reason, of installing cement parking blocks a few feet in front of the hot water heater in the garage. I've lived at plenty of places without those and managed ...
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0answers
162 views

Installing an 18kg (40lb) projector screen onto a concrete ceiling

I have a large projection screen that I need to install into a (seemingly) pretty stable concrete ceiling -- at least that's what I assume it is -- it sounds very solid when hit with a hammer, ...
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3answers
185 views

Installing hook on strange wall

I need to install some hooks on my wall, which I plan to use to perform elastic band exercises. Hence, I need to install these very well so that they will handle the stress properly. Situation is I ...
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2answers
10k views

Are there any advantages to using metal post spikes set in concrete when building a privacy fence?

My neighbor and I are considering alternatives to wood-in-concrete fence posts for a privacy fence that can have significant wind load in an area that gets up to -30 degree frosts in winter. The ...
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1answer
856 views

How tall can I go above ground with a concrete footing?

I am building a 20' x 20' foot deck with a 10' x 12' Pavilion in one corner, away from the house.I need the concrete footings for the pavilion to be flush or just above the surface of the deck. There ...
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4answers
12k views

How realistic is lowering a concrete floor?

So first off, I love basements, its almost like a fetish. Ook.. so this guy is selling a basement in his building and its perfect(got good water, electricity, comms, location and cheap!) except for ...
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1answer
428 views

Can I avoid the slab and run the new PEX through walls and interstitial space?

… and many other questions. The following is the incoming water for my small 2-story townhouse. This picture was taken in my downstairs hall closet. This is what I have figured out so far: (1) is ...
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1answer
139 views

Installing long 20ft metal poles in concrete around a football pitch

I work at a football club and I need to install some long 20 ft metal poles into the ground set in concrete. My question is how deep must the holes be and what diameter hole needs digging. The poles ...
0
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1answer
1k views

How should I extend a concrete patio under an existing deck?

I have a 18x20 second floor deck with three 6x6 support posts. Under the deck is a 40-year-old, well-settled, 12x20x6" concrete patio. The deck posts are set outside of the patio, set on footings ...
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0answers
78 views

Cracks in basement cement just poured

I saw this in my wall that was just poured. Contractor says its not a problem, I think it is.
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2answers
7k views

How do I get rust stains off my driveway?

I used fertilizer with iron and, unfortunately, didn't sweep adequately afterwards. Afterwards I ran my sprinklers and now my driveway and sidewalk are peppered with unsightly rust stains. What are ...