There are many common situations that can lead to flooding or dampness in your basement site. The need for draining a basement site due to a wet foundation, basement or crawl space is a common occurrence. Some of these problems can be remedied in the construction process, by allowing for proper drainage in and around the basement. The right contractor will be able to help design and build a basement or foundation that is suited for proper drainage, elongating the structural integrity of the entire building.
Sources of Basement Moisture
- In only a single inch of a rainfall, a 2,000 square foot home will be hit by 1,250 gallons of water. If the home is built without the proper downspouts, gutters and grading, some of this water is going to flow into the basement. Flooding is a common occurrence when the home is not built to protect against rainwater pooling around the home. All this water needs someplace to go.
- Moisture is also a consideration. It isn’t uncommon for a basement to be a moist environment due to humidity and other such issues. Concrete, the primary material used in the creation of foundations, is a porous material, which means that water and moisture can pass through the material very slowly over time.
While new construction is designed in such a way that it can avoid serious problems with free-flowing water, water issues must still be considered and protected against in as many different ways as possible.
Many basement water issues can be solved simply by handling problems with rainwater and surface drainage properly. The most common tools for this purpose include proper gutters and downspouts, and correct grading. When combining these three tools, you will have a better chance.
- Proper Gutters: Proper gutters will aid in preventing water from flooding into a basement, by collecting it and allowing it to be routed away from the house. Proper gutters are the first line of defense against flooding issues, but you also have to make sure that the home has proper downspouts as well to make sure the water is routed away from the home so that it cannot seep into the basement or foundation.
- Proper Downspouts: Downspouts and downspout extenders work by directing water away from the home so that it cannot seep into the basement. Generally there should be an impervious clay surface directly below the roof, around the home. The downspouts and the extenders should be long enough that they can divert the water away from the home entirely. It may take some time to guarantee that they are working effectively, by regularly monitoring the basement’s dryness level after rains.
- Correct Grading: The slope of the grade going away from your home can also help with proper drainage during rains. This may involve bringing fill to the site in order to create the proper grade, but it is well worth the effort when you consider the positive impact. When the slope grade is adequate to keep runoff moving away from the home, this can prevent excess water from pooling near the home which would ultimately seep down into the concrete foundation and cause flooding issues.
- Exterior Drainage Systems: If the building already exists, then one option that is available to you is to install an exterior drainage system. It is important to note that this can be a costly option, but it also happens to be one of the most effective options available to you. What it will require is that you have a contractor dig the area up around the foundation. You would then rebuild the area as if you were rebuilding a new home. If there are obstacles around the house, such as trees or shrubs for example, they may need to be removed prior to the installation of this system. This type of system will make sure that water is drained off and away from the property properly and that there is no risk of flooding or excess humidity.
- Waterproofing and insulation would both be installed simultaneously in most situations, in addition to making any necessary repairs to the structure. Traditional exterior drainage systems make use of free-draining sand in their backfill, and drain tiles which are placed next to or above the footing. There should be at least 12 inches worth of coarse aggregate present around the drain tile for adequate drainage.
- Interior Drainage Systems: There are different types of interior drainage systems for you to choose from, the mostpopularofwhich istheperforateddrainpipe, which you would have installed around the footing perimeter. Whatthiswillrequire is that you remove the concrete at the edge of the slab and then replace it. When youplacethedrainpipe under the slab, this allows for the area to be drained to a lower level than before.
- Similarly to the exterior drainage system, this system requires the use of a sump. It is important that the sump possess a completely airtight, completely childproof cover. The sump pump’s discharge needs to go to a location that cannot slope back toward the home where it is being pumped from, meaning that a proper grade is also essential with this type of drainage system.
- In situations where the walls of your basement are made from blocks rather than poured concrete, it will be essential that you place dimpled plastic sheeting at the wall bases as well as beneath the edge of the slab. You can think of dimpled sheeting as being similar in nature to egg crate. It allows for free drainage from the wall to the drainpipe, and it also happens to be more cost effective as compared to specialized channel drainage systems. In soils that have a low level of permeability, the system will not be able to accept rising groundwater unless an aggregate layer has been installed beneath the slab.
- Sump Pumps: There are additional considerations in situations where a sump pump needs to be installed. For example, you will need to acquire a building permit if a sump pump is being installed, which may not be required for other types of drainage systems. You also need to make sure that all utility lines and pipes are clearly marked before any digging is performed. A licensed and bonded contractor will know how to properly identify and mark these types of lines and pipes, or will know who to bring in to make sure that it is conducted properly.
Insuring the proper drainage for your home in order to protect your basement, crawlspace or foundation is absolutely essential. The right construction contractor can help you determine whether your home has enough protection or if more is necessary to achieve your goals. A contractor will also be experienced in identifying power lines, water pipes and other utilities that need to be avoided prior to the digging process, as installing drainage systems almost always involves digging.
This is why working with a licensed and bonded contractor is important. Make sure that you are choosing a contractor with the right experience and expertise, as well as someone that you feel comfortable with to help you complete this work. This will ensure that you are completely satisfied with the results.