Do you need gravel under concrete footing?

How to Pour a Concrete Slab for a Shed [Complete Guide]All you need to do is stake out your site, remove the topsoil, build and level your forms, spread and compact 4” to 6” gravel, lay out some rebar, and you're all set to pour your concrete slab.All storage sheds should have a foundation; whether pier, gravel or concrete.More items...

Footing thickness - 8 to 12 inches. Footing depth - varies based on frost line and soil strength (some footings can be shallow, while other must be deep)

Otherwise you could bury a pvc pipe in the concrete to run your gas line thru. Yes, you can bury the gas line. First I would bury a straight pipe larger than your gas line under the patio and then run the gas line in the pipe. If you ever need to replace the gas line it will be easy to remove.

With a brief look, a 16x16 area at 6 inches deep, you would need approximately 6.73 tons or 4.74 cubic yards of gravel. Concrete reinforcing is also recommended in high traffic areas and medium to large areas.

7 Answers. With a 1:3:6 mix for 100 cubic meter of concrete you would need 420 x 50kg bags of cement, 56 cubic meters of fine aggregate (sand and gravel passing through a 5mm sieve) and 79 cubic metres of coarse aggregate (gravel retained by a 5mm sieve).

You should NOT place a vapor barrier BEHIND the backer board. Where, pray tell, would any such collected vapor/water go? Answer:There's nowhere proper for such moisture to egress. The current best practice is to place waterproofing OVER the backetboard and just UNDER the tile.

In what order you should mix your wet concrete First mix the gravel with the sand. After that you add the cement. When gravel, sand and cement are mixed together properly, you can add the water. If you use Cementmix instead of water, your concrete will be waterproof after hardening.

Once the subfloor of proper thickness is properly installed then you can apply cement board directly to the subfloor material. ALL CEMENT BOARDS MUST be installed in a fresh bed of thinset. ... If you want the cement board under the shower tray then do so - doesn't matter.

With a brief look, a 20x20 area at 6 inches deep, you would need approximately 10.52 tons or 7.41 cubic yards of gravel. Concrete reinforcing is also recommended in high traffic areas and medium to large areas.

The good news is that you can pour the concrete in water. ... The biggest issue with pouring concrete under water is movement. If the water is moving, it can wash away the cement paste that's holding the sand and gravel together. But if the water is calm, then it's not a problem at all.

No, 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.

The good news is that you can pour the concrete in water. ... The biggest issue with pouring concrete under water is movement. If the water is moving, it can wash away the cement paste that's holding the sand and gravel together. But if the water is calm, then it's not a problem at all.

Most exterior slabs do not need a vapor barrier. ... In general, place the concrete slab directly on top of the vapor barrier, with the subbase below. ... The vapor barrier can be placed under the subbase, if the building is closed in when the dry subbase material is placed.More items...

Under ideal circumstances, acid etching works to expose the pores of the concrete. However, acid etching won't remove glues, mastics, caulk, and common stains, If your floor is marred or stained by these substances, you'll need to resort to grinding at least part of your floor.

The Surface Below the Cement Board Flooring: For ceramic tile floors, the cement board usually rests on a plywood subfloor (minimum 5/8-inch-thick exterior-grade plywood or OSB). ... In such wet areas, never install cement board directly over drywall or green 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..

45 cubic feet of concrete when mixed with 2.5 quarts of water.

In order to have enough concrete for 1 cubic yard (27 cubic feet), you'll require 2.2 bags of 60-lb concrete.

Since bags are only sold in whole (not half, or quarter) quantities, you'll need to purchase three (3) 60-lb.

bags for one cubic yard..

You don't need any cement board under the tub. It is far more important to have a sturdy layer of ply under the tub.

Because concrete slabs “float” on the soil, soft ground or voids underneath may cause unsupported areas to crack under heavy weight like vehicles. ... of sand or gravel over clay and other poorly draining soils to provide even support.

Laying a concrete driveway over an existing gravel one is possible, but it is not generally recommended. ... The kind of gravel that is intended to go under cement is typically a smaller grade than what is used for gravel driveways.

A hot tub requires a stable surface — whether it's a concrete slab, reinforced deck, or firmly compacted soil with crushed gravel.

There's also the option to have the hot tub installed in the ground but that still requires a concrete vault..

You don't need any cement board under the tub. It is far more important to have a sturdy layer of ply under the tub.

Applying a bead of polystyrene-compatible caulk or mastic to the top of the insulation board minimizes water infiltration behind it. For under-slab applications, the rigid foam insulation typically should be installed over a gravel base, with a poly vapor diffusion retarder between the gravel and insulation.

To create the base, spread a 4-inch layer of gravel over the excavated area. Level the gravel, following the initial grade, and cover it with a 1-inch layer of sand. Tamp the gravel and sand down with a plate compacter before laying the blocks.

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.

can you make concrete without gravel? A typical concrete mix cannot be made without gravel. Concrete is made from a mixture of cement, sand, gravel (crushed stone), and water. A mix ratio of 1 part cement, 2 parts sand, 3 parts gravel, and water, will give you a strong concrete mix.

Registered User. permanent wood foundations require gravel, not concrete or soil for the footings - every situation is a little different, but all footings need to bear on the soil/gravel/bedrock/ whatever is supporting the structure equally, or it's going to settle at different rates.

Using Rebar for Concrete Deck Footings Plain concrete deck foundations without rebar are acceptable under the minimum standards of construction established in the International Residential Code.

...

Footings with large bearing areas or unstable soil can benefit from adding rebar to prevent cracking..

Do I need a DPM under laminate flooring? Simply put yes. In order to prevent damp rising through the concrete floor and causing issues, a DPM should be used under all final floor types including wood flooring, laminate, vinyl and floor tiles.

InstructionsDig Under the Concrete. Dig out the soil, gravel, or other material from under the concrete, using a shovel and a pickax. ... Strike the Concrete. Lightly sprinkle the concrete with water to minimize dust. ... Pry Off Stubborn Pieces. ... Move the Concrete Chunks With a Hand Truck.Feb 19, 2020

A floating deck that is built close to the ground will not need to have any kind of deck footing. You can use some small concrete blocks where you can lay planks into grooves that are already there, or a post that sets into a pre-formed hole.

Gravel is a whole lot cheaper than a concrete, asphalt, or other paved surface. It can cost less than 1/2 of paved driveways. Even though you will have to maintain the gravel, it is inexpensive to do so.

The application of vapor barrier in exterior concrete is unnecessary due to the fact that water penetration does not matter. Any slab on grade that is enclosed and on the interior of a building should have a vapor barrier installed prior to pouring concrete, especially if flooring will be applied.

Installing pavers is very similar to concrete installation. You must start with a solid base and foundation. Most frequently, this involves digging down into the ground and removing the existing dirt and replacing it with gravel and sand.

Concrete Footings are typically poured in temporary forms constructed from plywood or 2x lumber. Wood stakes and braces hold the forms in position. The top edges of the footing forms must be level, and the concrete footings must be set to the dimensions specified on the plans.

Yes! A strong gravel base is required when building a concrete patio in order to prevent the concrete from shifting or cracking. Adding gravel under the concrete also provides a level surface for your foundation and adds proper drainage when there is pooling water.

One reason it is used as a backfill or sub-grade material. As with all material, it has to be placed correctly and compacted properly. Sand needs to remain damp as well as other material before placement of the concrete. If you want to build a road, use gravel, but this does not mean you will not have issues.

Excavate the slab area to a depth of about 7 inches, allowing 3 inches for a gravel base and 4 inches for concrete.

While not a requirement, a concrete slab foundation provides a solid, clean surface for your steel building and can help it last longer. Since the building will require anchoring to minimize shifting, pouring a concrete slab gives you a chance to pour footings as well.

6 inchesWall Footing Thickness. For masonry or concrete construction, the minimum foundation wall will be 6 inches. The minimum reinforced concrete footing thickness will be 6 inches or 1-1/2 times the length of the footing projection from the foundation wall, whichever is greater.

Whether you pour concrete for a walkway or patio, a strong gravel base is required to prevent the concrete from cracking and shifting.

Gravel is especially important in clay soil because it doesn't drain well, which results in water pooling under the concrete slab and slowly eroding the soil as it finally drains..

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.

InstructionsDig Under the Concrete. Dig out the soil, gravel, or other material from under the concrete, using a shovel and a pickax. ... Strike the Concrete. Lightly sprinkle the concrete with water to minimize dust. ... Pry Off Stubborn Pieces. ... Move the Concrete Chunks With a Hand Truck.

5 Bags# It takes approximately 5 Bags of Portland cement, 8 cubic ft of sand, and 20 cubic ft of gravel to make approximately 1 cubic yard (27 cubic feet) of concrete.

An average 1:2:3 mix contains one part cement, two parts sand and three parts gravel. To make 1 cubic yard of concrete, you'd need seven 94-pound bags of cement, about 1/2 cubic yard of sand and just over 3/4 cubic yard of gravel. The amount of water you use depends on how wet the sand is.

Laying a concrete driveway over an existing gravel one is possible, but it is not generally recommended. ... The kind of gravel that is intended to go under cement is typically a smaller grade than what is used for gravel driveways.

After the concrete blocks are laid, the voids can be filled with a cement-based mortar or poured concrete that contains small pea gravel....Do you need to fill cinder blocks with concrete?Block Wall ThicknessBlocks Filled per Cubic YardConcrete/Grout per 100 Block6″120.83 yd38″1001.0 yd310″801.23 yd312″651.54 yd3Mar 3, 2020

12 inches deepBy code, the bottom of a footing must be at least 12 inches deep and below the local frostline—whichever is deeper—and bear on stable, undisturbed soil that is free of organic matter. And the code requires a minimum compressive strength of 2,500 psi for the concrete.

Remove the loose soil with a shovel or garden spade. Continue to loosen and remove the soil around the outer edge of the footing in stages as you work toward the bottom of the concrete footing. Dig until the entire footing is exposed from ground level to the bottom.

Steps in Removing Concrete Deck Footings Using a spade shovel manually excavate around the footing at least 3/4 the way around and at least 2/3rds of the length of the footing. Dig until you see the footing wiggle a bit. The more you dig the easier the footing will come out.