Traditional concrete is a mix of fine particles used for sealing pavements. Unfortunately, its density causes waterlogging and might not be a great choice for parking areas and some walkways.
Pervious concrete is your holy grail if you are looking for a sustainable and better option. This comprehensive guide provides a vivid idea about pervious concrete and how you can use it to turn your building into dream work!
Hiking Machinery provide high quality concrete roller screeds to customers all over the world. The screed roller is the most suitable machine for permeable concrete construction because it does not vibrate the voids in the concrete.
Before we begin any further, let us wrap ourselves around the idea. Unlike other concrete mixes, Pervious concrete has a high porosity and is composed of cement, water, and coarse and fine particles, such as sand. Since this type of concrete mixture is highly porous, it helps the water from precipitation to easily pass onto the soil. How can it help? Well, pervious concrete reduces runoff, increases groundwater levels, and contributes to sustainable construction.
Is it worth it?
Since pervious concrete is a new concept, you might feel skeptical. However, pervious concrete has been acknowledged as the Best Management Practice for Stormwater by the US Environmental Protection Agency (EPA) as it also helps with pollution control. The main purpose of incorporating pervious concrete in construction sites is to reduce the demand for stormwater retention ponds and storm sewer capacity.
How can you install it?
Pervious concrete is the perfect stormwater retention basin for your home. Besides, they take care of the groundwater levels around the neighborhood. They also reduce runoff pollutants, which flow into streams and other water bodies.
As a newbie, you might be frowning about the procedure! Well, rest easy. It is surely not rocket science. Pervious concrete is mostly delivered to construction sites with ready-mix trucks. Besides, tools like hand screed, power roller screed, power trowels, etc., are required to level the ground, and a steel roller helps in increasing the strength. However, this concrete mix has very low water content. Hence the curing process requires it to be misted with water and covered for at least seven days.
Why should I choose pervious concrete?
Although it may resemble traditional cement in composition, pervious concrete lacks sand, making it an open-celled porous material that allows water to pass easily. Choosing this unique and effective concrete for your pavements can be beneficial. Why? Well, it has a high intake capacity of 3 to 5 gallons per minute per square foot of surface area, which can easily prevent runoff. Moreover, the rainwater is stored in the harsh aggregate underneath, which easily passes onto the ground. Pervious concrete pavements have interconnected voids that house aerobic bacteria that aid in disintegrating toxic pollutants and chemicals. The pavement acts as an independent retention area which also purifies the water before percolating into the soil.
Pervious Concrete: An economical solution?
If we look at the installation and life-cycle costs, we have our unmatched champion. While the material can be a bit pricey compared to the traditional concrete mix, it is usually installed 6 inches thicker instead of 4 inches for conventional concrete. Besides, here are some of the reasons that prove that pervious concrete is a cost-effective solution.
● Cheap installation charges
Traditional concrete construction wraps at more costs than you can imagine. For regular pavement, installing traditional curbs, gutters, storm drain inlets, piping, etc., usually costs more than pervious concrete constructions. Incorporating a sustainable material eliminates the need to install storm drains, underground piping, etc., thus cutting additional costs. Besides, grading is also avoided since pervious pavement does not need slopes to drain stormwater.
● Allows the use of existing sewer systems
The rising demand for rebuilding existing sewer systems for new residential areas etc. needs to be addressed immediately. This is why cities prefer pervious concrete construction since it reduces the need for municipalities to increase the stormwater intake capacity. It allows the use of an old sewer system without the need to reinstall a new one each time, taking care of extra costs.
● Better use of land
Pervious concrete constructions act as an independent stormwater management system. Hence, you do not need to install additional retention ponds, etc. Property owners can easily cut costs and use their land more efficiently and get a better return on their investment in the property.
● Life-cycle costs:
When it comes to the price, pervious concrete is more expensive than regular concrete. However, its life expectancy outshines the latter and can easily last up to 20 to 40 years after construction.
Making Pervious Concrete: How can I make it?
Besides buying it directly from your local store, you can also make pervious concrete right in your backyard. But isn’t it complex? Well, the main composition of this mix is the same as the regular concrete minus the sand. The basic ingredients include three parts rock, 1 part loose cement, and water. The rocks should be 3/8″ gravel, easily available at any nearby rockery. However, you should remember to choose rocks that have little to no sand particles. If you want a fine, smooth finish, make sure to use smaller rocks. Although, smaller rocks can challenge the uniformity of the concrete mix. A void content of 15 to 25% is required to make the perfect mixture.
For loose cement, you can choose any of the options from type I-II, type III-V, etc., that are available at any hardware store nearby. Make sure to add the cement in the right proportions. However, adding water to the concoction seems to be the most difficult step. Adding too much water to the concrete mix results in loose rocks. The best way to make sure that the water content is adequate is to wear gloves and make small balls that stay intact and has a shine to them. Besides, the water-cement ratio in pervious concrete mixture is 0.28 to 0.40.
Don’t lose hope if you couldn’t nail it on the first try! Even seasoned professionals often fail to get the perfect mix on the first attempt.
After getting all the ingredients in one place, mix them well under a shade. Why? Well, pervious concrete is often moisture-sensitive and can quickly dry and cannot be regained by adding water, unlike regular concrete.
On a budget? Well, you can still make pervious concrete on your home! How? Using old crushed aggregates, recycled concrete, and clay-brick aggregate are the most compatible components for pervious components. This is not only a cost-effective procedure but also reduces the carbon footprint, and the density may differ given the aggregate quality. The average density should range from 1420 to 1840 kg/m3.
How can I pour Pervious concrete?
Given the difference between the textures, pervious concrete requires compaction, aggregate interlock, and a porous surface for a proper pour and cure procedure. One can find different ways to pour pervious concrete. But which one would be the best option for you? Since this mix has a slow-lump texture, pumping might not be your best bet. Instead, it can be poured directly using a ready-mixed truck.
Moreover, this type of concrete is usually poured out as strips which provide even distribution and curing time. Strips are usually 12 to 20 feet long, and equipment like roller screeds (We mentioned in the previous article: the roller screed is the best equipment for the pervious concrete pouring) are the best equipment to cover larger areas. You can also use pervious mixture on a regular concrete slip-form paver. Since they do not require a straight pathway, it is done on slabs instead of using forms.
● Among the many advantages of pervious concrete, its environmental impact is surely a holy grail. Since the filtered stormwater reaches the ground easily, it creates a high-moisture content, and the interconnected voids create a perfect environment for trees to thrive.
● The water seeping into the ground plays a great role in maintaining high groundwater levels.
● Since the pervious construction is a stormwater management system, it eliminates the need for sewers and allows new residential buildings to use their previous concrete sewer systems.
While this unique material might be a match for you, it is not without its weaknesses.
● Not ideal for pavements with heavy traffic.
● Longer curing period.
● Needs regular cleaning to keep its permeability intact.
● Tests like slump test and compaction factor test are not applicable.
● Requipes special construction expertise.
For many floors or roads, good drainage is very important. However, regular concrete waterlogging and runoff are always a concern. This may result in an unfortunate accident and result in serious injuries. Hence, pervious concrete is the best solution for you. They act as an independent sewer system, thus preventing water logging, etc. Moreover, it helps you save some extra bucks and enjoy the warmth of your dream city.