Why You Need Drainage Under Pavers. Water can be a home's worst enemy. A build-up of moisture around your home can damage your foundation and your landscaping, cause mold and mildew, put you, your family, and your pets at risk of slipping and falling, and much more.
An influx of water that sits for a long period of time can damage your paver surfaces by weakening the cracks or chips already present. If your pavers are already loose, they may collapse. Flooding can also lead to erosion when soil and rock are transported and deposited into the area.
Pavers are permeable and are laid with small spaces in between them. These features allow water to run through them and back into the ground below instead of sitting on top, like it would with asphalt or concrete.
Materials to put under pavers might include mortar, sand, bituminous material or pedestals. Should I Lay Pavers on Sand or Mortar? Again, it will depend on several factors. The mortar set method is most popular and is typically used in pedestrian or vehicular areas where a rigid system is required.
Sand Bedding
Before laying the pavers, a layer of bedding sand is placed over the compacted base material. This layer provides a bed into which the pavers are set.
Whilst it is technically possible to lay pavers on bare, unprepared ground, this practice is not recommended as the ground will shift over time, causing the pavers to develop a sunken look, or even crack.
Crushed stone makes a solid paver base because it allows water drainage and is easy to work with. Like sand, crushed stone comes in several varieties. The best aggregate for paver bases is a quarry processed dense grade aggregate. Quarry processing creates a combination of 3/4-inch crushed stone and stone dust.
A GRAVEL BASE LAYER BEFORE SAND IS A MUST! Using sand alone to set pavers is not enough. The best and recommended paver base is 3/8-inch crushed gravel.
Lay a Good Base
If sand is used between each of the pavers, water will naturally percolate through it until it reaches the base. If the base consists of sufficient gravel and sand, the pavers will stay put. If the base is not thick enough, the paving stones could sink or the sand could wash out, causing shifting.
Unfortunately, pavers sink from time-to-time, most commonly because of uneven soil drainage. There is hope, however! To fix sunken pavers, follow the six-step process we've outlined below. Sunken pavers are quite the tripping hazard and can leave you with large, unsightly puddles of water.
The Problem With Polymeric Sands & Water Mitigation
Most polymeric sands don't drain water which meant small stones were used to fill the joints between the interlock. For driveways, this solution isn't a big issue but near a pool or patio, people prefer the smooth uniformity of polymeric sand.
It's simple science. Water moves in between things and by adding pavers to your landscaping, you're ensuring there are cracks and joints between them, which allows water to drain through. One thing to remember though is to allow sufficient space between pavers to allow water drainage.
Because open-graded paver bases allow water to flow freely, they're a great option for permeable paver installations or environmentally friendly landscapes—if you live in an area that's prone to flooding or has drainage issues.
Decreased Drying Time: Properly sealed pavers do not allow water to absorb inside them. This significantly reduces drain time. Pavers that dry more quickly, are much less likely to support mold and algae growth or develop efflorescence.
Just like all other construction installations, you also need a base for pavers if you want them to not move from their place. Sand is ideal for this purpose as it forms the perfect base. You need to make sure that you only use high-quality sand for creating a base under the pavers.
The amount of sand you use can make or break your paver installation, so it's best that you use no more than the recommended 1 inch. Here's why: A sand layer that is too thick can create waves in your patio during the installation. Pressing pavers into a thick sand bed may result in misalignment and a messy look.
Laying pavers on top of concrete is a viable project in many situations. The process can save you money and avoid labor-intensive removal. Always lay a proper sand foundation over the concrete before adding pavers.
There are two different methods of laying pavers, and they depend on the type of pavers you're laying. Concrete pavers are generally laid on a sand bed, whilst natural stone pavers are best laid on a mortar bed.
Start with the gravel that's sitting atop the soil. It must be compressed down so it's laid on the soil in a stable and neat manner. Add a thin sand layer on the gravel – it serves as the paver's base. Also, compress it to make sure that it's level with the surrounding pavers' base and stays fully flat.
Wind string and tie securely around the stakes at ground level. Remove the garden hose or chain. Slide the carpenter's level all the way around the rectangle along the string. The ground should be level for pavers to drain, but with a slope of 1 inch to every 4 feet in length, to encourage drainage.
Porcelain pavers can be laid directly over existing grass or lawn as 'stepping stones' or to create a pathway, but for better stability of the pavers, the grass beneath the pavers should first be removed, together with a shallow layer of the topsoil.
Acidic cleaners: Harsh, acid-based cleaning products and stain removers can damage the seal and finish of your concrete pavers. Bleach: This alkaline solution may be effective for other household uses, but it can discolor concrete pavers that have been colored or stained.