Basement Waterproofing

Basement Waterproofing is the act of keeping moisture out of your basement. Simply put, the hope is to keep the water out for good.

Waterproofing a basement, done correctly, is maintainable, reliable, and a key to transforming your basement from a health hazard to an area in your house that nourishes the foundation of your home.

Exterior Waterproofing

Goal: To keep the water in the soil from reaching the foundation and soaking through the concrete or cold joints (the separations between the parts of the basement, wall, floor, and footing).
How: There are a few new standards that have been introduced: Polyethylene Vapor Barriers placed on the soil before the foundation being poured. After the walls are in place, the Polyethylene is wrapped up the exterior of the footing and foundation wall, creating a barrier between the concrete and the soil. A “French drain”, which in this application is perforated pipe, is then installed near or at the footing on the exterior, covered with crushed stone, and the back fill (also crushed stone) is then applied around the rest of the exterior concrete foundation walls. Soil can now be reintroduced around the home and landscaping can take place.

Pros: Stopping the water from reaching the foundation is your first line of defense. Exterior systems help to prevent the contact of water with the foundation, footing and floor slab. The drain can then channel the water away to a designated spot on the land.

Cons: Exterior systems aren’t always installed during the construction of a new property.  Depending on your budget, doing a full system can cause a lot of collateral damage which can include, and is not limited to, disrupting landscaping, removing fixtures, fencing, patios, decks, hatchways, and depending on your foundations stability can cause further damage to the property if not designed and executed precisely.

 

Interior Waterproofing Systems
Goal: To redirect the water, fix leaks, and remove the water infiltration of the foundation to outside using the grade of the land.

How: Again, standards have changed recently, introducing new technology in this industry.  Your floor slab is broken out (jack hammered; it’s not as bad as you think), the fill in that trench is removed to expose the footing of the foundation.  A drain system is designed to match the perimeter of the basement and is placed into the newly designed trench.  A polyethylene vapor barrier is adhered near the sill plate (the wooden beam that rests on the top of your foundation wall) on the concrete, and is extended down into the trench to meet the drain. Sump pumps and sump grates are installed at the lowest point of the basement to which the drain is then directed. The trench is then filled with crushed stone and the floor is then concreted back to the original condition. Water enters the walls, footing/wall joint, or comes from under the concrete floor and meets the drain which channels the water to the sump pump. The sump pump activates and removes the water out of the home, through a pipe, which can be submerged and connected to a small dry well that can be installed on the property.

Pros: Compared to exterior systems the collateral damage is minimal.  They are faster to install, quality is maintainable, serviceable, and you get your basement floor space back. The systems can be finished over with proper design and construction.  They can be designed with power supplies for battery back ups in case of power outage.

Cons: If you have a finished space, and you have a major issue, the demolition can increase the price. There are so many different styles and no industry standards that are enforced.

 

Current Industry Practices and Standards:
http://www.nawsrc.org