French Drain System Installations
Can an interior French Drain System be installed in my basement without a sump pump? Can French Drain piping discharge into my trap/sewer system?
In some homes, there is a sewer trap below the basement floor. This is where your main sewer pipe leads to the exterior sewer system. In theory, a drain system can terminate into this trap area if the main sewer line cap is removed. But in most municipalities, it is illegal to discharge a French Drain System into a city sewer. Also, if the sewer backs up- your basement will flood with sewage. If your home is connected to a septic system discharging into your septic system could lead to a complete septic overload.
How should water seeping between my foundation walls and floor be repaired? How should water seeping up through cracks in my basement floor be repaired?
Installing a perimeter French Drain System is the only correct repair for this situation. A French drain will keep the water table below your basement floor and prevent any further leaking. All French Drain piping should terminate into a sump pit and a quality sump pump should be installed
Can I seal up water that is entering my basement from between the floor and the foundation walls, or in my basement through cracks in the floor?
No. This problem can only be rectified with the installation of a French Drain System.
You cannot prevent water from accumulating from under your basement floor! This is the level of the water in the ground in your area (known as a high-water table). This water table is also at the same level under your neighbors’ basements. An exterior French Drain System will not prevent this from happening neither. If an exterior or interior drain system was installed, the water level under your basement floor would still be as high as the bottom of the drain system piping.
Do I need to install a French drain around the entire perimeter of my basement if water is seeping between my foundation wall and floor along one wall only?
A French Drain System can be installed along one wall only-it can also be installed along two walls or in a very small area of only 5ft if needed. Generally, if your basement is leaking along three walls, we recommend a full perimeter drain system at this point. French drain system pricing is by the linear foot. If a small system needs to be connected into an existing system, you might pay three times the amount per foot on a small job due to the additional setup and preparation time. Again, a partial drain system can be installed and we can always add on to it if needed in the future. Things to consider when requesting a partial perimeter drain system installation.
Are you going to finish off your basement? Installing a French Drain in a finished basement is costlier and more damaging to your basement. Installing these systems in an unfinished basement is much easier and less expensive.
Do I need to remove the wall or drywall in my basement prior to the installation of a French Drain System?
No! In most cases, we can install a drain system with all walls in place. It is recommended that all base moldings are removed prior to starting as the drywall at the base will incur minor damage. When reinstalling base moldings, the damage will be covered over. However, some drywall areas above the base might take on minor damage during the installation process as some concrete floors are much more difficult to remove than others. We have installed complete drain systems in finished areas with literally no damage to drywall at all. Bottom line, you should be prepared for some minor spackling and paint after our work is completed. If a finished wall partition is built too far from the foundation, some drywall might need to be removed to complete a drain system.
If a French Drain System is installed along one wall only, will water be push to another section of the basement?
Absolutely not! French Drain Systems are also called pressure relief systems. Upon the installation of a full perimeter or partial perimeter drain system, the water pressure is being relieved in the areas the drain system has been installed. A partial perimeter system will not prevent the rest of your basement from leaking.
Should my French drain system be installed on the interior (under my basement floor) or on the exterior around the perimeter of my foundation?
On homes that are not under construction, it is always easier and less expensive to install an interior drain system. If you are having a new home built and the building site is set up high and there is an option to run the drain system piping to a low area, then you can install an exterior system. We still recommend an interior sump pump for a backup.
Also, visit our French Drain System page for the pros and cons of interior systems vs. exterior.
The holes in PVC piping should always be facing upward! This subject is not open for discussion! The holes faced upward in the beginning of time and always will face upward. Minerals, iron bacteria and silt will always settle to the bottom of the drain system trench. Holes facing downward will clog and contaminate the interior of the pipes causing the french drain system to fail prematurely.
If you have flooding in your basement and the water is entering from under the foundations slab, you will need a sump pump. If you are considering a French Drain system installation, you will also need a sump pump to complete the job. Sump pumps can also be installed as insurance. This does not mean you will never have a flooding situation in your basement. It will only prevent the water from becoming much deeper than the floor surface.
If you have a consistent water table and often experience power failures, you will need a battery backup system. A battery backup unit runs on a 12-volt deep cycle marine battery. A battery backup system is specifically designed to work together with your primary AC pump. If the power to the primary pump fails or if the primary pump malfunctions, the battery backup system will take over. All battery backup systems are wired to a charger that is plugged into your homes AC power supply. When the primary pump fails or the power goes out the battery backup will be on a full charge and take over the job. The charging unit usually has an alarm that will sound to let you know the backup system has been activated. When purchasing a battery backup, be very cautious as the prices vary tremendously. It is important to purchase a quality unit that will handle a large volume of water. Power failures are quite popular during heavy rains and hurricanes. So, a unit that pumps 119 gallons per hour (GPH) will probably not be sufficient. Basement Waterproofing Solutions recommends a backup system that will pump a minimum of 1500 GPH.
The primary reason a homeowner should consider a sump pump in their basement is to prevent ground water from rising above their floor. Sump pumps are also installed as a component of a French Drain system. This is where all French Drain piping terminates. Sump pumps can also be installed as a preventive measure.
Submersible and pedestal pumps are the two common types of primary sump pumps; A submersible pump is smaller than a pedestal pump and its motor assembly is completely sealed. The motor sits directly on top of the pumping mechanism and the entire unit can be placed completely under water. The motor assembly on a pedestal pump is mounted several feet above the pumping mechanism and the motor cannot get wet. Bigger is not better when comparing a submersible pump to a pedestal pump. A basic or primary sump pump should run on household AC current. The most common size pumps are 1/3 and 1/2 HP. These units will pump between 2000 and 4500 gallons of water per hour. All sump pumps should have an external float switch or internal pressure switch to operate the pump automatically so when a water table fluctuates the pump will turn itself on and off.
A battery back-up pump system should only be used as a secondary pump to prevent flooding should the power or primary pump fail. These systems are complete with a small DC operated pump, a 12-volt deep cycle marine battery (sold separately) and a charging system to keep the battery at maximum charge. The charging system also has several lights and alarms to keep you informed when there’s a power failure, the battery’s life is near end or if the primary pump fails. Caution should be taken when purchasing these systems as their pumping capacity can vary from 119 gallons per hour (GPR) to 2500 GPR. Also, affecting the pumps capacity is the height of the discharge piping. Some battery back-up systems advertise an attractive GPR pumping capacity at 5-foot head height and drop down to 1000 GPR at 10 feet.
AC, DC converters are other options for power failures but we found the battery back-up systems to have a longer run time. These units will run an AC pump on DC power.
Water powered sump pumps are another option for a back-up systems but max out pumping only 1000 GPH. These systems are connected directly to the city water supply in a home and will not work if the homes water is supplied by a well. The plus side of this system is it will continue to operate as long as there is city water.
Primary 1/3 HP pumps can be purchased in a store between $80 to $250. If an existing sump pit is already in place, professionally installed prices range from $400 to $650. ½ HP pumps generally cost $100 more than a 1/3 HP.
A quality battery back-up pump system installed will cost $800 to $1100. We don’t recommend a homeowner installing a battery back-up as we have witnessed many professionals install them improperly.
What would you recommend homeowners shopping for a sump pump look for to ensure they have one that will do the job properly?
A submersible pump with an external float switch is the preferred pump by most professionals. Stay away from inexpensive sump pumps. It’s a great example of being penny wise and dollar foolish. Stay away from pedestal pumps. A pedestal pump is a pump that has the motor assembly mounted several feet above the pumping mechanism. These pumps are difficult to install and can tip over easily. When they tip over they don’t work. Sump pumps are usually installed in storage closets in the basement where people store their luggage. It’s very common to tip a pedestal pump when grabbing your suitcase causing a major flood while on vacation.
How a pump is discharged can make all the difference. If a quality pump is installed with a battery back-up and it is not discharged properly, the pumps can fail.
All leader downspouts should be diverted away from the home. If a homeowner currently has a sump pump, they should be aware of how often the pump operates during heavy rain events so they can stay prepared. Homeowners and landscapers should never raise the ground or flower bed above the top of the homes foundation. Running a quality dehumidifier during the summer months will keep the air in their basement and home dry and healthy.
A pressure relief system is French drain piping installed under a basement floor/slab. When drainage piping is installed under a basement floor, it will relieve the water pressure from under the floor in a given area.
A water table is the level of water in the ground. This should not be confused with the water level in a deeper well known as the aquifer. A water table can vary according to specific weather precipitation. During heavy rains and spring thaw, water tables will be high. During dry weather seasons, water tables will lower. Some water tables are always high even during droughts.
Unpleasant odors can come from several situations:
- High humidity levels.
- An undetected foundation leak.
- A previous flood that was not dried completely.
What recommendations do you have as I am planning to finish my basement to create additional living space?
We urge you to do a complete inspection of your basement after a heavy rain or during the spring thaw. Many times, we have been told by homeowners, they never had a basement leak until they finished off their basement. In most cases, the leak was always there but no one spent any time in the basement prior to converting it to living space- so the leak went undetected.
A basement is always prone to have some kind of leak. Even if it has a drain system that is 100% perfect, there are several flooding situations that can occur. Most basements have a hot water tank or heating system, and most plumbing pipes run through the basement ceiling. Anything can happen with these items that can flood your basement.
When installing drywall, have your contractor keep it, a minimum of ½ inch off the basement concrete slab. When base moldings are installed they can be placed right on the floor covering up the ½ inch space. Drywall is like a sponge and can absorb water 4Ft up the wall. Mold loves drywall and will grow very quickly on it. The base moldings do not absorb at the same rate as drywall and do not mold up as quickly.