Exposed aggregate concrete is a construction technique where the material at the surface of the concrete mix is left uncovered.
Normally, this material is broken into small pieces of hard rock or other materials. Exposed aggregate concrete has become very popular in recent years because it allows architects to create many different designs that can be found on walkways, patios, driveways and other structures.
The installation consists basically of pouring the normal concrete mix into the formwork, compacting it and allowing it to set. Once the concrete is dry, the formwork can be broken away revealing an exposed aggregate concrete surface that is rough in appearance. In order for this to be achieved, the concrete mix must have a very high cement content and a coarse aggregate size.Exposed aggregate also known as pebble dash is a type of masonry coating that consists of small pieces of stone or rock set in concrete base material such as cement or an adhesive after being fixed with a binder. The most common use is on exterior surfaces like block walls, brickwork or stucco siding. It's often used to cover the grey colour of cement which doesn't look attractive outside buildings. It can come in different colours to suit your taste including white, black, brown etc. Exposed aggregate concrete surface, exposed aggregate paving, exposed aggregate driveway and exposed aggregate finish have become popular over the years because it provides several benefits like easy installation, low maintenance and long-lasting quality. There are different types of distinctive exposed aggregate finishes that were developed by using a variety of techniques which include:
Involves breaking large pieces of stone into smaller fragments and then laying them regularly across the surface of the plinth. The joints between stones must be tightly packed to prevent water from seeping in behind the wall. It's recommended, especially for a plain concrete and sand base, to use a sand-cement mortar mix or another type of cementing material for this kind of job.
It's very similar to rubble finishing where small pieces of rocks are laid across a foundation surface instead of on top of it after being fixed with a binder. The difference is that pebbledash doesn't require the use of a fixative and instead water is used to smooth over the surface. However, it's important not to apply too much pressure as you wipe down the surface otherwise some of the stones will end up breaking.
This involves applying a thin layer of mortar or adhesive on top of a substrate that contains crushed rock that has been graded into appropriate sizes. Tile dashing is normally done with either a roller or trowel where you have to evenly spread out the material onto your wall before proceeding with laying tiles on its top. The best part about tile dash is that it requires little maintenance and can be applied on vertical or horizontal surfaces.
The main reason why exposed aggregate has become very popular over the years is that it provides several benefits like easy installation, low maintenance and long-lasting quality. It's also an economical choice compared to other kinds of materials used for surface finishes like timber, stone or plastic. Exposed aggregate can come in different colours to suit your personal preferences and tastes making it perfect for exterior landscaping projects. Exposed aggregate is normally available in black, white or brown colour options which make it suitable to be installed on driveways, walking paths etc.
Exposed aggregate is a simple procedure where you can do it by yourself provided that you have the right tools and equipment. This means that following these steps will allow you to install exposed aggregate on your own:
First, create formwork (a box-like structure) that will act as an enclosure for the exposed aggregate mix or laid concrete mix. Formwork is very important because it gives shape to your product which would be smooth and flat on top if no formwork was used. The size of this structure depends on how large or small your project is; generally speaking, it has to be big enough to accommodate the desired outcome without any compromises.
After pouring the base, start adding the stones and materials that you've chosen for your exposed aggregate job. Add-ons can include hydrochloric acid, liquid limestone or any other acid wash or stone from sea beds. You should whole mix them with wet cement or adhesive depending on what kind of subtle aggregate finish you're going to do after laying the stones. To make things easier, choose a uniform-sized stone instead of using a variety.
It's recommended to remove any excess material before proceeding because doing so will help the surface dry faster which ultimately results in a better quality product at the end. Exposed aggregate concrete is normally allowed to dry for several days before applying any sealing material but if it rains during this time, you'll have no choice but to wait until everything dries up again first. Using decorative concrete or concrete finishes for exposed aggregate finish can give a finer texture and appearance.
Once your exposed aggregate has dried up enough, apply a sealer on its surface to create polished aggregate or even decorative aggregate using surface retarder and also protect it from three elements that can compromise the condition of your project.
Applying too much sealant will result in a glossy surface which can be very slippery when wet so make sure to test out several samples of slip resistant, skid-resistant sealant on concrete slabs before choosing the best one for your job and the amount best suited on a concrete slab. Testing is the most common type of method to ensuring standard concrete has the desired ratio of a non-slip surface. You may even want to hone the final product for a different finish.