Best answer

Subgrade—this is the native soil (or improved soil), usually compacted. Subbase—this is a layer of gravel on top of the subgrade. Base (or base course)—this is the layer of material on top of the subbase and directly under the slab.

Answered by: Mister Jojo Date created: Jun 23, 2022

What is a cement slab?

Asked By: fevid Date created: Jun 17, 2022

Ways To Use A Cement Slab Essentially, a cement slab is a flat, solid pouring of cement that is allowed to dry and harden in place. The most common use for a cement slab is as the foundation for a home, and many contractors believe that a cement slab foundation is the most secure option out.

Answered By: Fab Date created: Jun 17, 2022

What is normal concrete cracking?

Asked By: Alex Martelli Date created: Jun 09, 2022

Probably the single most common reason for early cracks in concrete is plastic shrinkage. When the concrete is still in its plastic state (before hardening), it is full of water. This water takes up space and makes the slab a certain size. As the slab loses moisture while curing it gets a bit smaller.

Answered By: hvgotcodes Date created: Jun 12, 2022

Can I pour concrete in a hole full of water?

Asked By: Andrew Whitaker Date created: Jun 24, 2022

For a structural, engineered assembly, having water in the bottom of a form is a no-no, because it can liquify the soil, and make the final assembly height unstable. That is, things may settle as the wet mud underneath flows away, and slowly dries out.

Answered By: Cheers and hth. - Alf Date created: Jun 26, 2022

What happens if plaster of Paris gets wet?

Asked By: Michał Perłakowski Date created: Jun 14, 2022

Can plaster of paris casts get wet? Absolutely not! A wet cast may not hold the bone in place because the cast could start to dissolve in the water and could irritate the skin underneath it, possibly leading to infection.

Answered By: Caner Date created: Jun 16, 2022

What is the minimum depth for a concrete slab?

Asked By: Matti Virkkunen Date created: Jun 15, 2022

5 cm thickWhatever you plan on doing, your concrete slab should be at least 5 cm thick. That is the bare minimum of a concrete slab thickness. This is the thickness of the concrete slab alone and it doesn't include the gravel base, if you are using something like that.

Answered By: thatguy Date created: Jun 18, 2022

What is a structural concrete slab?

Asked By: Shubham Chaudhary Date created: Jun 15, 2022

A concrete slab is a structural feature, usually of constant thickness, that can be used as a floor or a roof.

A slab-on-ground is supported on the subsoil and is usually reinforced with reinforcing bars or welded wire mesh..

Answered By: Rick James Date created: Jun 16, 2022

Can you pour a concrete slab over a septic tank?

Asked By: Noldorin Date created: Jun 22, 2022

You should never pave over your septic tank. Although soil compaction is not a major issue for septic tanks, there are other dangers presented by placing an insecure septic tank underneath concrete and heavy vehicles.

Answered By: Paul Kulchenko Date created: Jun 25, 2022

What is reinforce concrete slab?

Asked By: Arthur Azevedo De Amorim Date created: Jun 20, 2022

A reinforced concrete slab is a crucial structural element and is used to provide flat surfaces(floors and ceilings) in buildings. On the basis of reinforcement provided, beam support, and the ratio of the spans, slabs are generally classified into one-way slab and two-way slab.

Answered By: Slipstream Date created: Jun 23, 2022

What is the ratio of concrete slab?

Asked By: sebaferreras Date created: Jun 21, 2022

A concrete mix of 1 part cement : 2 parts sand : 4 parts coarse aggregate should be used for a concrete slab. Concrete must be placed within half an hour of mixing. Place your concrete into your formwork; work the concrete into awkward places and corners using a shovel or trowel.

Answered By: Ben Date created: Jun 23, 2022

Is Thinset under cement board necessary?

Asked By: Andrew Date created: Jun 23, 2022

Not only is thinset a critical component underneath cement board but the other critical component is the fasteners. And you won't have the fasteners if you are trying to install it over concrete.

Answered By: SethMMorton Date created: Jun 25, 2022

Related Question Answers

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What is concrete slab on grade?

Slab-on-grade or floating slab foundations are a structural engineering practice whereby the concrete slab that is to serve as the foundation for the structure is formed from a mold set into the ground. The concrete is then placed into the mold, leaving no space between the ground and the structure.

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What size rebar do I need for a concrete slab?

Rebar in patios, basement floors, footings and driveways may vary from size 3 to 6. Contractors sometimes use the “1/8 Rule,” meaning the size of the rebar is 1/8 the thickness of the slab. For example, a slab that is 6 inches thick might have rebar marked as size 6 or 3/4-inch.

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How do I find a water leak under a concrete slab?

Signs Of A Leak Under Concrete1). There is water or damp spots on your floor. If hot-water lines are leaking, this may also lead to warm spots on your floor. ... 2). You can hear the sound of rushing water underneath your floor. ... 3). There is a significant increase in your water bill.Jan 10, 2021

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How do you fix moisture in a concrete slab?

Installing sub-drains at the building perimeter to carry water away from a building: This technique incurs some cost but is the most effective solution to tackle any further detrimental effect of moisture on the concrete slab. Place a vapor retardant underneath the new floor finish.

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Do you have to plaster after removing wallpaper?

In some cases, and this is only possible to judge after removing the wallpaper to see what is underneath all layers, a plaster will be the best option, specially if you have a case of too rough and uneven areas.

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Do you have to seal concrete after painting?

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Do you need Thinset under cement board?

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And you won't have the fasteners if you are trying to install it over concrete..

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Do you seal concrete before or after painting?

As previously stated, concrete is porous, and can absorb moisture. If you are painting interior concrete it is vital to seal the concrete. This will prevent moisture from seeping in underneath the paint and causing mold.

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What does troweling concrete do?

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Why does my concrete slab sweat?

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How do you break concrete slab?

With small slabs of concrete, such as patio squares or air conditioner pads, you can also have one person pry up the slab a few inches, using a demolition bar, while another person strikes the slab with the hammer. Prying up the slab has the same effect as digging underneath it.

LinusGeffarth

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Why is my cement driveway sinking?

Why Does Concrete Sink/Settle? Slab settlement is the movement a concrete slab experiences when the soil below can longer support the weight of it. You experience cracks and movement when most likely, the soil changed underneath the concrete.

Nicolas Gervais

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What are concrete slabs used for?

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hrbrmstr

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What is cement slab?

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Can I use sand under concrete slab?

Pour concrete over a solid, well-drained base Because concrete slabs “float” on the soil, soft ground or voids underneath may cause unsupported areas to crack under heavy weight like vehicles. Pack about 4 in. of sand or gravel over clay and other poorly draining soils to provide even support.

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What is a concrete rat slab?

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What is concrete slab-on-grade?

A slab-on-grade is a type of shallow foundation in which a concrete slab rests directly on the ground below it. A slab-on-grade foundation usually consists of a thin layer of concrete across the entire area of the foundation with thickened footings at the edges or below load bearing walls in the middle of the building.

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What is the purpose of a vapor barrier under concrete slab?

The use of a vapor barrier (more accurately termed a vapor retarder), having a water vapor permeance of less than 0.3 perm is frequently used to retard the flow of moisture through the slab. These vapor retarders are typically polyethylene or polyolefin sheeting materials.

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What animal would burrow under a concrete slab?

Rats, mice, moles, voles, gophers, and several other types of ground-burrowing rodents are natural diggers, constantly seeking out shelter and sources of food. Sometimes, they choose to make their dwelling space underneath concrete foundations.

Darek Kay

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What is the best way to break up a concrete slab?

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greg-449

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What are footers on a concrete slab?

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Is crushed concrete good for drainage?

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Can you cover concrete with a tarp?

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What is concrete etching?

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What is sand mix concrete used for?

Sand Mix is an extremely versatile concrete and mortar mix, ideal for products including but not limited to: Repairing wide cracks in concrete and masonry. Shallow concrete repairs or construction from ½” to 2” Thick mortar bed applications, such as underneath ceramic tiles.

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How do I remove concrete from my lawn?

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How do you know when concrete is bad?

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How do you prevent frost heave in concrete slab?

We've found that putting in a layer of insulation underneath the concrete actually helps to prevent frost heaving from penetrating into the underlying soil and thus prevents the soil from freezing and expanding to the point where it pushes your concrete around.

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What is the minimum thickness for a concrete slab?

2 inchesWhat is the minimum thickness for concrete.

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Four inches is most common for a slab.

The thinner applications would include drives, walkways, slabs and footers, just to name a few..

Dean Taylor

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Should I cover concrete from rain?

If rain is in the forecast, you should postpone a large concrete pour until conditions improve. Even if rain isn't predicted, you should always be prepared to cover the concrete with a tarp or plastic sheeting just in case. Make sure to seal the edges so rainwater can't seep underneath.

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What is the difference between a concrete slab and a cement slab?

The difference between cement and concrete Concrete is basically a mixture of aggregates and paste. The aggregates are sand and gravel or crushed stone; the paste is water and portland cement. Concrete gets stronger as it gets older. ... Cement comprises from 10 to 15 percent of the concrete mix, by volume.

Mariano Luis Villa

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Do you need to use thinset under cement board?

Not only is thinset a critical component underneath cement board but the other critical component is the fasteners. And you won't have the fasteners if you are trying to install it over concrete.

Burhan Khalid

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How do you remove concrete overlay?

Once you have a place started where the overlay is broken through, continue to remove the concrete overlay. This is easily done by prying up the concrete from underneath and breaking it into smaller pieces. Use a flat scraper with a long handle to drive under the overlay and lift up.

Philipp Schwarz

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Should I seal concrete before painting?

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cedricbahirwe

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How much does a 30x30 concrete slab cost?

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rayryeng

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What is a composite concrete slab?

Composite slabs comprise reinforced concrete cast on top of profiled steel decking, which acts as formwork during construction and external reinforcement at the final stage.

Amir Saleem

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What is a floating concrete slab?

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ntalbs

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What is normal moisture in concrete slab?

MFMA recommends the relative humidity level for a concrete slab for a non-glue-down maple floor system be 85% or lower and for glue down systems the concrete slab relative humidity level should be 75% or lower before installation.

Tsvetomir Tsonev

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What is the minimum thickness of a concrete floor?

Standard concrete floor slab thickness in residential construction is 4 inches. Five to six inches is recommended if the concrete will receive occasional heavy loads, such as motor homes or garbage trucks. To prepare the base, cut the ground level to the proper depth to allow for the slab thickness.

Jeffrey L Whitledge

Guest

What is the purpose of plastic sheeting under a concrete slab?

The sand layer cannot dry downwards by vapor diffusion because of the plastic sheet—it is a vapor barrier after all. In fact that's why we have it under the slab. We want a vapor barrier under the slab. ** We want to prevent water vapor from coming up from the ground into the concrete slab.

Axel Fontaine

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What is the thinnest concrete slab?

Four inches is most common for a slab. The thinner applications would include drives, walkways, slabs and footers, just to name a few. With this type of application, both a fine and coarse aggregate are required. Products labeled “High Strength Concrete Mix” are ideal for these types of applications.

hasen

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What is the tolerance of a concrete slab?

Traditionally allowable tolerances of concrete floor slabs were determined by checking the slab surface with a 10 foot straightedge. Common tolerances were 1/8 inch or 1/4 inch in 10 feet.

Domi

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What can I use for concrete expansion joints?

A pliable material is used (asphalt coated, cork, plastic) to construct these types of joints. The material should extend the depth of the slab and extend the full width of the slab. Ideally, for expansion joints on the exterior of a structure, sealing these joint is preferable.

Gufran Hasan

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What causes concrete blisters?

Why Does Concrete Blistering Happen? It begins when either bleed water or bubbles of entrapped air move through the concrete and are unable to escape the surface. Usually the surface was sealed too early during finishing, resulting in the hidden voids of air and bleed water underneath the mortar skin.

Slava Vedenin

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Can you pour concrete over a wood deck?

Benefits of Installing an Overlay Over Wood The concrete is rot-proof and insect-proof. This process provides a waterproof area underneath the deck which can then be used during inclement weather (if the deck is on the second story) or just for storage.

ford04

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Can you put Trex over concrete steps?

Yes Virginia, it can be done! You will have to build a frame over the existing stairs first and then add your composite stairs. ... Composite boards require closer support beams underneath than lumber.

Klaus Byskov Pedersen

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What material will Concrete not stick to?

Almost any non-pourous work surface is fine. I use wax paper, glass, Teflon sheet, Faux Bone, sheet plastic, Plexiglas, etc. The concrete will take on the finish of the surface against which it sets. If you just place it on Teflon or similar, the concrete will leak from underneath.

Laurent Perron

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Do I need a permit to pour a concrete slab in Florida?

Yes, you will be required to pull a permit when removing a tree, including dead trees. Do I need to obtain a permit to pour a concrete slab, patio, or driveway? Yes, a site plan will be required with a description of what is being done.

Eric Wendelin

Guest

Does homeowners insurance cover concrete driveway?

Rather, they happen because the earth underneath shifts. After periods of rain, the soil underneath your driveway could shift or wash away. In turn, this weakens the driveway concrete, putting pressure on it and cracking. Generally, home insurance will not cover this issue because it is deemed a long-term problem.