Using a dryer final mix results in a stronger slab and prevents water absorption by the underlying soil. Lay your bricks in Set the bricks down one by one, starting on the near side before working outwards. In fact, clay soil can have its advantages, as it holds water well and is rich in nutrients. Riprap are large, irregular-shaped rocks â¦ Clay soil has poor drainage, and it softens and erodes when it gets wet, so flagstones can shift and break with regular foot traffic. Continue spreading and compacting the crushed rock in 3-inch layers until the base reaches a total depth of 12 inches. Spread crushed rock -- containing roughly equal parts 3/4-minus stone (stones that are 3/4 inch or less in size) and stone dust -- over the area in 3-inch increments. A former nationally ranked sport fencer, Gerard also spent several years as a fencing coach and trainer. This type of soil is generally more fertile than sandy soil, but it will always need amendment of some sort if you want to grass â¦ How to Fix Pitted and Cracked Garage Concrete, How to Pour Concrete Landscape Curbing by Hand, The Family Handyman: How to Pour Concrete, Schlatter Family Site: Pouring the Concrete Slab. Born in West Virginia, Jack Gerard now lives in Kentucky. Mark out the area for the flagstone patio or walkway, using several garden hoses or ropes. If the clay soil is very soft, excavate the soil to a depth of several inches and mix in gravel to create a firmer base for your slab. Keep the top of the concrete slab moist to help ensure even curing. The soil below should be at a slight grade so that when water drains through the sand and gravel and reaches the poorly draining clay soil below, it runs off of the soil instead of forming pools beneath the rock. A floating slab spreads the structure weight over the entire base instead of at strategic supporting columns. The terminology used for soil support systems, unfortunately, is not completely consistent, so let's follow the American Concrete Institute's definitions, starting from the bottom: 1. For example, a flagstone might be perfectly flat on one side, but if you flip it over, part of the opposite face sits up higher than the other half. Place 3/8-inch or 1/2-inch rebar inside the frame to provide additional strength to your concrete slab. Laying turf on clay soil mixed with sand. While you may want a smooth slab surface, adding control joints that are approximately 1 inch deep gives you more control over where the cracks occur and helps to hide them from view. Concrete shrinks as it dries out and this usually results in cracks. Step 3. Here's my questions: 4) Riprap. Clear and level the area where you plan to pour the concrete slab. The sand and rock layers must be perfectly level before installing the flagstones. Over time and especially during rains, the native soils could eventually mix with the compacted class II base material and eventually weaken the paving system. The patio is to be 4m x 3m. To get the necessary slope (1:60) the surface of the patio will need to be less than 150mm from the dpc - about 100mm is the best I can do. Fill in the gaps between the stones with your choice of coarse masonry sand, pea gravel or decomposed granite. Southern California soils commonly are clay or silt based. The slabs can be seen to be sloping away from the house and a slope, or fall, of 15mm per 1.5 metres is a good fall for a patio. â¦ How to Install Concrete Bricks for Lawn Edging, How to Build Your Own Flagstone Mowing Strip, How to Make a Garden Path With Slate Slabs, Paver Search: A Guide to Installing Flagstone Pavers, University of Minnesota SULIS: Paver and Brick Installation, This Old House: How to Lay a Bluestone Patio, Pave Tech: Installation Guide to Paver Walkways and Patios, How to Use Fieldstone As a Border Around Gardens, How to Make a Walk With Pea Gravel and Concrete, How to Prepare a Yard for Landscape Stone, How to Lay Flagstone With Crushed Bluestone Over Concrete. When stone flags are laid to town â¦ Build a wooden frame for your slab, using a carpenter's level to make sure that the walls of the frame are leveled properly. Compact the 3-inch layer with a plate compactor; a hand tamper works well on small areas such as walkways. There are two ways to go about preparing your clay soil for laying the turf. Mix the concrete according to package directions, using as little water as possible so that the concrete mix is wet, but not saturated. For flexible construction, clay pavers are laid in exactly the same way as concrete blocks â a screeded bed of grit sand is prepared, the blocks are laid by hand, cut-in and compacted. Smooth the surface and begin laying down the slabs for your shed starting from one corner and working your way out. Remember to use a spirit level on each and every slab once placed, if not level use a mallet and wooden block to hammer until it â¦ Control joints should be placed every 4 to 10 feet across your slab, depending on its size. Â© Copyright 2020 Hearst Communications, Inc. Disassemble the frame from around the concrete slab after five to seven days have passed. Use the back side of a bow rake to push the crushed rock around. Choose stones with shapes that fit together together so you leave no more than 1 to 1 1/2 inches of space between stones. Allow the concrete sufficient time to settle and begin to cure before troweling the top surface of your slab.