Try to avoid the following 7 FRENCH DRAIN MISTAKES

A french drain is a great solution to keep the outside water away from your house’s foundation. It looks like a linear trench with a perforated pipe in it. The pipe should be about four inches in diameter. This trench should be at least two feet deep and up to 6 inches wide. Such parameters are optimal for the facility to perform its function smoothly.

The pipe inside the trench should be covered with a certain kind of gravel whose pieces are about the size of a walnut or grapes. There shouldn’t be any sand mixed with this gravel.

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The french drain usually runs to the lowest position in your yard going down-slope from your house. That allows the excess water to flow rapidly through the gravel and be caught by the pipe. Such a system that is normally located underground can make your yard dry even after the heaviest rain.

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There should also be a slight slope at the bottom of the trench. It can make up one-eighth inch for one foot of its horizontal extension. Many yards have some steeper slopes, so the bottom of the French drain, especially, in the part that runs past your foundation, can have a gap between the down part of the trench and the pipe. It means that it cannot be parallel to the steep surface of the ground and in some places, it is shallower than in others. You should avoid this because then the excess water may not run into the pipe but flow immediately across the yard and make it muddy.

The main french drain detail is the trench that is properly excavated across your yard and then lined with the appropriate filter fabric that is made of geotextile and meant specifically for French drains. There is also some bedding material that can cover the bottom of the trench.

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So, while installing this facility, try to avoid the following FRENCH DRAIN MISTAKES:

Usual Mistakes You Can Make While Installing Your French Drain

1. The Wrong Type of Gravel Is Used

You need this drainage rock to ensure the perfect permeability of the French drain. This filling material should consist of natural stones of mostly the round shape.

When the stones are round, the water flow will be smoother and faster. There is one more plus in such a shape. No separate piece can break off from the stones and clog the French drain. Repairing suc clogs is a big challenge, so you need to be very attentive about the choice of the rock.

The perfect option here is 1 ½ inches round rock. These washe round stones are ideal for your facility.

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2. The Lining of the Trench Is Missing

Lining the trench with a special kind of fabric is essential. If you have a long swath of this fabric which is not cut to pieces, it is the best variant. Though, you can also use separate srips of it that are at least 12 inches long. Then, you will need to overlap them and the ends of the strips should be reliably fastened with the secure staples. If you notice the excess fabric while laying it, just fold the loose material. You will be able to cut it off after the end of laying.

The fabric should be overlapped in a certain direction that will allow the water to flow. The fabric on the lower part of the trench needs to be overlapped with the one on the upper side but not vice versa.

Your system will guarantee you smooth and effective performance for many years only if the lining is laid correctly. It means the correct direction and the appropriate kind of material. You can use the method of wrap installation that is described here or opt for some other one if it is effective enough.You need to remember these things:

  • The French drain without lining material will not last you long.
  • The lining fabric should be of high quality to be used for many years.
  • Never install the perforated pipe without wrapping it into the drainage materials or it will get clogged very quickly with soil or dirt that will be washed out by the excess water.

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3. Adding the Excavated Soil Back to the Trench Should Be Avoided

Many homeowners do not know what to do with the soil that has been excavated from the trench and they just make a simple decision about putting it on top of their new drainage system.

The contractors also do this because they want to leave the space around the trench after the work is completed clear and nice-looking. Never do this if the soil is not just a sod strip that is placed on the trench for decoration and making the trench fit into the yard. Even if you utilize such a method, the strip needs to be very thin without additional dirt on it.

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4. French Drain Mistakes: The Slope of the Drain Is Not Positive Enough

If you do not know how to tell if French drain is working, pay attention to the overall condition of your drain pipes. If the water stays inside pooling or puddling around, your system is working poorly and you will have to reinstall it soon. So, it is always better to check this matter at once, in the process of installation.

If you have noticed something like that, take the instant measures to improve the situation before the completion of the entire work.

However, it is easier just to prevent such a scenario. You need to make sure that the pipes are sloped correctly. The drainage that is located on the plain surface will never work properly and let’s explain it to you why it is so.

Different Types of French Drain Slope: 

  • Slants Are Missing. It means that the drainage pipe has been located on the flat surface without any angles for the water to flow down. Such a system needs rather high water pressure to work consistently but it is not available. If there is no slope, the water will not flow down. So, it will not be drained and just stand making problems with the excess moisture in the lower layers of your house.
  • Some Spots Are Lower Within the Trench. When the surface of the trench’s bottom is not smooth enough having some dips or lower spots, the water can pool in them. The amounts of such pooling water in these dips can be rather hazardous because the available water will attract the roots of trees that are constantly searching for moisture. That is why they will grow in the direction of this settling water. Then, step by step, the roots will penetrate the drainage system and prevent the water flow or even block it completely. The drainage system with dips on its bottom will attract the attention of tree roots sooner or later. The French drain may be seriously damaged by them, and, if its integrity is broken,the harmful vermin or bugs will invade the system.
  • The Slope Is Set Up in a Negative Position. The negative slant is extremely undesirable. The slope should run from the house’s foundation down away from your yard but not vice versa or the water will not run at all. If the trench or the pipe has acquired the opposite grade, the excess water will never flow into the pipe but be saturated by the ground and soon come back to the foundation of your home and into the basement. So, as you see, the negative sling of your French drain cannot even be considered as an option because it can threaten and damage the foundation and the entire building structure.
  • Try to Reach the Ideal Slant. The best water flow is normally provided by a 1% grade slant. In this case, the excess water will drain correctly into the pipe and be driven away from the foundation and lower parts of your home. The gravity works most efficiently at this angle so it will do all the job properly.

5. The Installation of the Drainage Is Made with Gravel Only but Without a Pipe

hen you want to save some cost and effort on the installation of the drainage system, leaving out the pipe is not the best idea. If the drain pipe is missing, this may become a big issue over time.

The matter is that, if the water flow is too heavy (as it happens in spring when th esnow is melting or the water is flooding), the excess water will not be redirected effectively because it may not find its proper way without being directed by the pipe. The pooling surface water needs the exact way of flowing from your house.

If it cannot find this way, it may spread all over your yard, get to the foundation and inside into the basement.

Only if you have installed the perforated drain pipe of four inches in diameter, surround it with gravel, and wrap it with the proper fabric, it is capable of working efficiently. Moving all the excess water away from the foundation and preventing its pooling is the main function of the French drain and it should be able to perform it consistently.

6. Installing the French Drain Around House Is an Incorrect Solution

You have already noticed that any seasonal flooding never passed by your house. You usually get the flooded basement or crawlspace, or any other lower area in your home. It means the worst scenario – your French drain is installed incorrectly. It goes around the house or too close to the foundation. If the case is like that, you will inevitably get continuous problems with the excess water.

So, you need to remember that the French drain distance from house is important. The durian should be installed at the distance of at least 3 feet from the house’s foundation. You should also consider this distance equally from the deck, patio, or porch.

Now, let’s speak a bit about the French drain depth. The standard depth required for the French drain is two feet. In any other case, there is a risk of damaging it by electricity, gas, or water supply facilities that can go over the trench. The shallower installation can be dangerous both for your family and your neighbors. If the drainpipes have been damaged despite all the precautions, find the phone number of the federal helpline and ask them to help in any case of the damaged facilities. The experienced technicians who will be repairing the issue will also mark the areas of your French drain location to prevent it from further unearthing.

7. Directing the Downspout into the French Drain Can Be Harmful

A lot of homeowners believe that they can route the gutter spouts into the French drain system directly. It is a bad mistake because the drainage system can get overwhelmed with all that excess water when it is raining heavily. This flow of water can damage the entire system badly and your household may receive a severe backup of water into the basement.

The installation of a catch basin in front of the drain area looks like a much better solution. Only after that, you can connect the water flow from the French drain into that basin. Additionally, the catch basin can stop all the leaves and other debris from entering the French drain and clogging it badly.

In conclusion, remember that the installation of the French drain in your backyard is not a simple process. You can make some French drain mistakes while doing it and they will cause bad consequences and much damage to your house from the excess water collected in its lower layers. As a result, you can receive seasonal flooding, severe water backups, and a lot of moisture in the basement or crawlspace. You also need to take into account that if the French drain has ever been installed too close to the foundation, you are likely to need some help from professional plumbers and have it reinstalled correctly.

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