why do i need crushed stone under concrete

what do you use under concrete?

We don t use recycled concrete under any concrete floors we install We use mostly gravel and sometimes the stone I would also recommend a vapor barrier of 6 mil poly on top of the stone before you pour the concrete Click here to post comments Join in and write your own page It s easy to do How? Simply click here to return to Concrete ....

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What Kind of Crushed Rocks Do You Use for Artificial Grass ,

Turf Application Your crushed rock layer is typically 1 to 4 inches deep within a 5-inch excavated area After spreading the proper rock ratio onto the ground, you need to compact it to a level ....

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should I use stone under my cellar floor

My cellar is dirt Should I lay stone before I lay the concrete A Y First determine how much head room you need You may need to dig out some of the existing sub-base before adding crushed rock Check the building codes in your area Once the sub-base is ready and level add two to three inches of 3/4 inch crushed rock over it...

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How Much Crushed Stone Do You Need? A Sure

Crushed stone is a material that is typically used as a base or underlayment, upon which the stuff that actually shows -- for example, the concrete of a patio-- will rest Guessing is rarely a good solution to such dilemmas when undertaking a big project, so let s look at ,...

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Why Put gravel under concrete? 2019 UPDATE

May 06, 2010 0183 32 Coarse gravel, like 57 stone, under a slab is used as a capillary break to prevent ground moisture wicking up through the concrete All good concrete needs the bottom almost as flat as the top, creating a uniform thickness to maximize strength The concrete is prone to cracking wherever the slab gets thinner no matter how thick it is...

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Gravel under concrete footing

Some builders fill the bottom of their excavation with 4 inches of crushed stone, and then pour their footings on top of the crushed stone If you do that, water can flow readily under the footings If instead you pour your footings on either undisturbed soil or compacted crusher-run gravel, it s a good idea to include a few 4 pipes through ....

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How Much Base Material Do I Need for Walkways, Patios and ,

How Much Base Material Do I Need for Walkways, Patios and Driveways Brick pavers, when properly installed add considerable beauty to your home and are very functional as well Without the proper walkway base material laid beneath the pavers you will run the risk of them sinking or settling unevenly...

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Aggregate required under footing?

I am going to pour an 8 deep x 16 wide concrete footing under the frost line 4 down , with a block wall on top of it going up to grade The soil is very heavy, solid, red clay Do I need to have aggregate under this foundation for drainage, or can I pour the cement directly onto the soil? Usually, I believe 6 of stone is recommmended, but ....

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How to Build a Gravel Shed Foundation Essential Guide

Use 190 crushed stone mixed with finer crushed material and dust 21-A , NOT gravel Remove the topsoil, it is compressible and will shift under the weight of the gravel and shed, causing you pad to settle and shed to tilt Make sure to build your pad level, especially if building on a slope...

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Does anybody use sand as a base before they pour concrete ,

Concrete cracks no matter what you do, that is why you see regular spaces groves or lines in sidewalks, its a control joint to allow cracking to occur there rather than where it wants Otherwise, what is under a slab depends on the ground you are pouring the slab on, some soils don t need anything, some need a ,...

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Gravel or Sand Below a Foundation

Jun 05, 2007 0183 32 RE Gravel or Sand Below a Foundation SlideRuleEra Structural 30 May 07 20 19 During placement of concrete foundations, it gives a route for any excess water in the concrete to escape without causing problems...

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Gravel under garage floor?

I like crushed stone because it drains best, and naturally compacts best Find out what gravel means in your area,if you are not sure Without trying to add confusion to Dick s and Charlie s ideas, another way to go, if you decide to insulate under the slab, is to extend the out 2 feet beyond the garage and pour a monolithic slab with ....

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Crushed stone vs concrete for footings HomeImprovement

Crushed stone vs concrete for footings After doing some work in my crawlspace, I got to thinking about crushed stone for footings instead of poured concrete Specifically, with regards to footings that you might use for a deck or house support piers but not as a footing for the foundation necessarily...

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What kind of gravel can I use as a base for my retaining ,

You normally use 3/4 crushed stone, unwashed You would also normally want a good 2-3 of crushed limestone screening on top of the gravel under the footprint of the wall itself It all has to be very well compacted or it will settle...

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Shouldn t I Have Gravel Under Concrete Footers?

Sep 29, 2012 0183 32 Our contractor is telling me that a layer of gravel is not needed under the concrete footers I called the inspections office in my area and spoke to the lead inspector in my area and he told me the same thing, but couldn t tell me why gravel isn t needed under the poured concrete I called the inspector for a second opinion...

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Best Gravel for Your Driveway

The final layer of a gravel driveway consists of smaller gravel blended with coarse rock dust, known as fin Crushed stone 411, which is a mixture of 57 stone and coarse rock dust, is a ....

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3 Reasons Why It s Important To Use Crushed Stone Under ,

Apr 28, 2014 0183 32 Concrete may seem strong, but after many years, elements, and pressure, it will eventually crack So in order to make your concrete last as long as your money that went into it, adding a layer of crushed stone under a slab of concrete will increase the life of your investment Here are 3 reasons why a layer of crushed stone is important to the life of your concrete...

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Do you need to put gravel under a concrete pad? Yahoo ,

May 12, 2008 0183 32 I am a concrete worker, and the answer is y It helps with the drainage, and also with the settling of the concrete, so the cracks are minimal You want 4 inches of gravel under 4 inches of concrete Any less concrete and you will have problems in the near future Dig down 8 inches in your backyard the size of the pad you are pouring...

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gravel or crushed stone under concrete Mobile Crushers ,

Jan 27, 2015 0183 32 gravel or crushed stone under concrete heavy industry is specialized in the design, manufacture and supply of crushing equipment used in mining industry The product range of our company comprises mobile crushing plant, jaw crusher, cone crusher, impact crusher, milling equipment, ball mill, vibrating feeders, screens and equipment for ....

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Choosing Best Gravel For Concrete Pad

Jan 06, 2008 0183 32 Re Choosing Best Gravel For Concrete Pad does 3/4 mean 3/4 and 57 or 5/7? mean 5 to 7 cm stone? I compact it all the same, but doesn t seem to do a whole lot except aroudn the edg...

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How important is gravel under a concrete sidewalk? Home ,

Oh - and BTW - rounded/river gravel is not best - a CRUSHED rock product though same size as gravel - typically 1/2 or 3/4 minus for this purpose is much better - does not move around as much under load, though under a sidewalk not anywhere as near important as under a driveway where rounded gravel can cause significant issu...

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Shed Foundations Made Easy The Best Types Explained

Sep 17, 2012 0183 32 Generally, smaller sheds of up to 8 6 do not need a foundation Small sheds can be rested on crushed stone with either treated wood foundations or concrete foundation blocks Large sheds will need to have strong foundations Considering Backyard Buildings smallest shed size is 8 8, all of our sheds will need a foundation setup prior to the ....

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Do I need crushed stone/gravel under my retaining wall ,

Apr 22, 2008 0183 32 You need 4 of crushed gravel under your wall to allow drainage so that frost doesn t heave it out Just as importantly you need gravel behind the wall Lay a length of weeping tile 6 perforated pipe along the base of the wall at the back and cover it with 12 of gravel, a piece of tar paper and then some earth...

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Sand under slab instead of gravel

Mar 04, 2013 0183 32 I d want to know why the sand is so wet in the first place If it s just due to weather exposure and would drain/dry if under cover, that s one thing If it s due to high water table, I might be inclined to build up the slab area with crushed stone aka gravel in ,...

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Bases and Subbases for Concrete Pavement

concrete or asphalt paving equipment that can achieve a smooth surface As such, the use of stabilized bases under a concrete pavement can contribute to achieving a high level of smoothness for concrete pavements Figure 6 shows an example of an asphalt-treated base, and Figure 7 shows a cement-treated open-graded drainage layer...

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What is Crushed Stone 57?

57 Crushed Stone This stone varies in size from a 4 sieve to a 190 inch, This product is cubical and used for projects with a specification for the crush count or mix The crushed stone of 190 inches is an aggregate size, and a 190 inch square screen has been used to crush and reduce the size The Best Uses for 57 Crushed Stone The best ....

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Gravel under footings Structural

Jul 07, 2004 0183 32 Compacted crushed stone can be used and is the only foundation used in all wood dwellings Never caught on here but have 20 or so around for 15 years or more without apparent problems It will take and darn good engineer to convince me that round rocks can be used under a footing even compacted...

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Proper Subgrade Prep Concrete Construction Magazine

Sep 20, 2007 0183 32 The top 6 to 12 inches of the backfill under the slab should be filled and compacted with well-graded gravel or crushed material Walls are typically backfilled with the removed earth or with a granular, open-graded material, says Tull...

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Bases and Subbases for Concrete Pavement

Bases and Subbases for Concrete Pavements AASHTO classification A-6 or A-7 soil groups or the Unified Soil Classification System CH, MH, and OH soils o Degree of moisture change within the soil Other factors responsible for non -uniform foundation include variability due to a number of reasons including, natural causes, excavation and...

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How Much Does Crushed Concrete Cost? HowMuchIsItorg

When crushed concrete is charged by the ton, the price can vary anywhere from 6 to 14 per ton By the yard, crushed concrete can cost anywhere from 20 to 30 Generally, the more you purchase, the lower that price will be per yard or ton Mainslandscapesupply, for example, sells its crushed concrete from 2295 to 2495...

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