moldy area of basement water leakage

Basement Leak Problem Solving

During my years of travels in the roofing and contracting business, often I received calls and performed inspections and work in an attempt to stop rain water from entering people’s basements.   I learned that often, basement water can be decreased or even eliminated entirely without incurring a large expense and without performing a large intrusive project. It is important to attempt the simple inexpensive  “adjustments” first, in order to avoid the larger project. Hopefully, some of the smaller simpler and less expensive repairs will stop the water infiltration, however if they are not successful at holding back the water, they simply become completed chores in your “ process of elimination’ towards learning more,  and eventually understanding and solving the problem. While many basements can be “dried out” with fairly simple means, some problematic homes do have a high water table and such a situation may require extensive reparations. Initially, the goal is to perform all of the simple measures with the hopes that the problem will go away, because if the problem persists after these positive changes have been completed, you may have to face the fact that a larger project is needed: most often that larger project is not necessary.   Simple maintenance and drainage suggestions mentioned in this article will often do the trick.


When you learn to camp out at the Boy Scouts or the Girl Scouts, one of the first lessons is learning how to pitch your tent for overnight shelter.  They always say “Pitch your tent at a high spot”. Without fail, often people will mistakenly pitch their tent at the location with the best view or the prettiest spot,  with all other criteria being a lower priority. When that thunder and lighting shows up at 2:00 AM, the camper is helpless. The tent pitched at the top of the hill is shedding water nicely and since the tent is located on the apex, the water that runs off of the roof and sides of the tent is reaching positive slope in the direction away from the tent, so that no water is pooling beneath the tent floor and while the campers are awakened by the storm and the thunder, they are dry because gravity and drainage are working in their favor.   Conversely, the tent at the bottom of the hill is dry at the beginning of the storm, however during the deluge some or all of the water is beginning to naturally collect and pool beneath the floor of the tent. The floor of the tent is supposed to be waterproof, but after years of setting up and breaking down, that connection where the floor canvas material is stitched to the tent walls has become loose and fatigued; in addition to some of the scuffs and scrapes the floor has sustained over the years. As water enters the ground area beneath the tent floor, the water level begins to rise putting water pressure on the floor and the floors weak connections to the tent walls.  The more rain that enters the area beneath the tent, the higher the water level rises, and the more pressure that is put on the floor. Eventually the water naturally determines that it is just as easy for enter as it is to stay out; so the path of least resistance at some of the defects allows water into the tent and the campers are not happy about it.


In the initial attempt to solve a home’s basement water, we need to think about it in a fashion similar to camping.  The simplest thing for the camper to do to keep the water out, is not to focus on repairing the tent floor, rather to focus on simple adjustments that can be performed to keep the water from breaching and pooling beneath the floor.   Luckily, the camper can take down the tent and move it to another location; homeowner’s do not have that luxury, so here are some of the simplest suggestions that can be performed in order to solve your basement water problem. Unfortunately, if these suggestions do not work, you may end up at the realization that you do have a difficult and elaborate problem, but most of the time this is not the case.  For example, if your entire property area has a high water table that is higher than (relatively speaking) your basement floor, then these suggestions likely will not work for you. If you have a water table problem, there are things you can do to alleviate or solve, however unfortunately someone chose a difficult place to set up your “camp site”.


When a homeowner realizes they have water entering the basement, they often decide to focus on the basement floor and an attempt to “waterproof” the basement floor.    I suggest that you should focus on all other factors prior to focusing on the basement floor or foundation walls. Focusing on the basement floor, would be like the camper leaving the conditions as they are and simply attempting to waterproof or fill all of the defects where the water is breaching; while this may eventually be necessary, solving the problem in the simplest easiest fashion involves employing a strategy that focuses on all of the other relevant inexpensive factors first.   Unless attempts are 100 percent complete, strong and continuous, performing waterproofing on the inside of the basement is often largely ineffective and often, water problems can be solved without ever performing any work inside the basement. While it may make sense to fix some foundation cracks eventually, most scenarios can result in greatly decreasing or entirely eliminating basement water without ever performing an interior repair. (side note: cracked foundations are better repaired if one digs down and reveals the crack and repairs it from the outside, where the water pressure originates.)

Basement Leak Water Mold Mildew
  1. LANDSCAPE ADJUSTMENTS: One of the most important  and simplest rules for decreasing basement water, is to slope your land away from the home so that surface water will naturally run away from your foundation.  Dirt and turf can be added to raise the level of the landscape or to simply divert drainage flow in this regard. It is very common to see the land surrounding a home, incorrectly sloping back towards the foundation. Many homes have good positive general land slope, however the garden areas immediately surrounding the house often might slope back and drain toward and into the foundation.  Garden borders often create a barrier not allowing the water to drain away. In many cases, a foundation and basement will not leak even if the gardens do not offer positive drainage, however if your gardens are receiving water and channeling it beneath your basement floor, you might consider adding soil to slope it away. Many homes will be “forgiving enough” to stay dry while allowing direct rain to collect in these low areas, however allowing direct rain to collect in a low spot is an entirely different scenario than allowing high volume roof drainage water to pool in these trouble spots.   If you have low areas surrounding your home and you can not add slope, then you must at least stop the roof drainage water from dumping in these low problem areas. Extend your leader pipes and gutter's downspouts past the low spot so that the outer end of the pipe is depositing the water past the low spot and effectively onto the soil that slopes away, so that the water will not retreat back around the foundation causing a pool beneath your basement floor. Some homes have very low cellar windows such that the addition of soil for positive slope, would cover the window opening. In such cases, buy a window well so that you can pile the dirt up high against the window well, create positive slope, but still preserve the window opening.   If you have a scenario where creating positive slope would otherwise cause your turf to be higher than the upper edge of your foundation, then you have a pretty serious problem that may require extensive drainage pipes and possibly mechanical water pumps.

  2. MAINTENANCE:    Any experienced professional will tell you that wherever anyone is attempting to control water flow, maintenance will always be required.   Flowing water carries items and debris, therefore keeping water flowing in an optimal manner and in the desired direction, will always require maintenance which includes removing the debris  items that the water carries in order to preserve water’s desired “path of least resistance”. If maintenance is not performed, water will always cause blockages at the lower spots which causes the water to rise to higher spots or undesired areas.   In short, gutters and drains must be periodically cleaned in order to keep them flowing so that the water will stay controlled. When leaves or debris clog a gutter or a downspout, the water will overflow and be deposited in undesirable areas such as that garden that slopes backwards toward the foundation.  Even areas of ground drainage need to be maintained by removing debris so that the path of least resistance allows the water to naturally exit properly. As an improvement, gutter cleaning and maintenance can be decreased by installing gutter guard products that keep the gutter from clogging and decrease the maintenance frequency, but when there is debris and a requirement for water flow, there is always going to be a need for maintenance so choose your gutter guard products wisely so that they can be easily maintained.  The point is to eliminate gutter clogs that cause the water to flow in an undesired manner. Proper gutter maintenance will not only decrease water infiltration, but it will also preserve your home, decrease window and trim rot and decrease foundation damage.

  3. DRAINAGE WATER CONTROL:  There are two distinct categories of drainage which are 1) the direct raindrops that hit the landscape and 2) the roof and home drainage.  For the most part, we hope that the direct rain that hits the ground is positively sloping away from the home so that we can focus on the majority of the controllable water which is the roof drainage.  While all of the water matters, the roof drainage is typically the lion’s share of the problematic volume and control of it may be enough to keep the basement dry. Often water might enter a basement solely at one corner, in which case the leader pipe or downspout at that corner might be dumping the water into a garden that slopes backwards.   Often, people will correct basement water by eliminating that downspout and hoping that the water makes it to the other downspout at the other end of that gutter. Eliminating a downspouts might solve the basement problem temporarily, but that downspout was usually necessary and complete elimination of such can cause problems to re-occur during a heavy downpour when the drainage system gets inundated and over-run.    If you solve your basement problem by eliminating a downspout, consider re-introducing that previously removed pipe in a new location that continues to promote proper gutter drainage but somehow keeps the water away from the undesired location(s). Proper design suggests that each gutter should have the redundancy of at least two outlets or downspouts in order to perform properly in most conditions. If the removed downspout had previously been located at the same corner where the basement leaks, consider a creative new location in that same gutter but perhaps 20 feet away from the corner and additionally directing that water further away from the trouble.  Rather than entirely eliminating a downspout at a troubled area, try to relocate that downspout so that it carries the water away. Common practice is to simply lengthen and extend the downspout out past the garden. Downspouts or even solid ground pipes or “storm drains” can be added to extend the drainage pipe past the low spots to deposit that water where desired; or even carry the water entirely off of the property. For optimal water control, perform repairs as needed and keep gutters and downspouts in proper working condition.

  4. ELIMINATE WATER PRESSURE IN THE BASEMENT:    All of the above techniques are in an attempt to keep the water from flowing down around the foundation and filling  the space beneath the basement floor. Many years ago, basements were able to be kept dry, even though the home had a dirt floor and a loose block foundation; they accomplished this by keeping most or all of the water from flowing toward the foundation.   Earlier in this article, I had explained that having a high water table can be a serious problem, but do not confuse a high water table with having a high level of water beneath the basement floor. With a high water table, the water is actually migrating through the land  soil and raising the water level in an almost uncontrollable manner. If you do not have a high water table, then accomplishing control of the drainage and landscape water will keep the level of water around your foundation and under your floor, to a minimum and eliminate the water pressure that causes infiltration.  If you control water pressure, you may not need to perform any foundation or floor crack repairs at all. If you do have high pressure water, those repairs would have to be perfect to have a positive affect.


Some homes are somewhat forgiving, and do not allow basement water infiltration even though some amount of water is allowed to run back toward the foundation. Many homes have drainage stone or gravel under the basement floor so that a small amount of under-floor water can exist and yet not leak or cause a problem. Other homes leak, even when only the smallest amount of water breaches.  Through the process of elimination, and attempting to adjust minor items first, over time you will learn “what works”, what does not work, and to what extent you will need to control your water. While some difficult and expensive problems do exist, in most cases, logical improvements can solve your problem and once gutters and drainage have been properly adjusted, all you need to do is perform your maintenance program regularly to keep your drainage clear, keep the water flowing away,  and keep the basement dry.


Alex “The Roofer” O’Hanley

6/20/18

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