Exterior Basement Waterproofing

Many waterproofing companies will come inside your basement and try to capture the water after it's come through your walls. There are cases when this is the right option, but to really solve a basement water issue, the best solution is outside.

What is Exterior Basement Waterproofing?

At its simplest, exterior basement waterproofing is a process of removing the dirt around a foundation, and creating a new barrier on the outside of the block or poured concrete wall that will not allow water to permeate through the foundation. This used to be done by trowling a think coat of mortar over the foundation wall, but now specialty rubberized coatings, that will last for decades, are painted on the surface.

Why Exterior Basement Waterproofing?

Most other waterproofing options are simply a bandaid on the real problem. Whether that's covering interior walls with waterproofing paint, or even creating a vapor barrier with plastic sheeting, you are still stopping the water after it has passed through the wall. This can cause structural issues as well as allow moisture to be one step closer to your basement, opening up the possibility of damage to walls and carpeting, and everything else you've stored in your basement. Interior sump-pumps have their place, but if water can be kept from ever entering the interior space, that is the ideal and more permanent solution.

Exterior Waterproofing Benefits

The benefits are many, but the primary one is done correctly, exterior basement waterproofing will solve the problem once and for all.

• Stopping water at its source
• Lessens the possibility of structural damage to your foundation due to years of water seepage
• It lowers the humidity of your basement, thereby reducing airconditiong and dehumidifying costs.
• Is a final solution, not a bandaid fix

Exterior Basement Waterproofing Considerations

There are many things to be aware of from the early planning process, all the way to the end of the project's completion.

• Electrical/Plumbing - It is always a good idea to have all utility lines marked before beginning a project. This includes incoming power lines, gas lines, sewer lines, phone and cable lines, sprinkler systems, etc...
• Landscaping - Do you want your landscaping saved? Sometimes larger bushes and trees might not survive the move, so it might be necessary to replace them after the project is complete.
• Access - Depending on the scope of the project it may be necessary to move fencing, or drive through neighbor's yards, etc... to access the worksite. This, of course, will all be discussed before the project is begun.

How Exterior Basement Waterproofing Works

Here's a quick step-by-step guide of what you can expect when the A-1 pros come out to do your exterior waterproofing job.

1. Excavation - For most houses, the first step will be to move any landscaping that may be around the foundation for later replanting. After that is completed, depending on the size of the project, A-1 will either dig a trench along the foundation by hand or bring in a small excavator to dig down to the footer for the foundation. Typically the trench might be even a few inches below the top surface of the footer, this will assure that as the water drains down the outside of the foundation, it'll run off and away from the wall.
2. Footer Drain - Once the trench is dug along the foundation, our technicians will shore up the dirt wall for safety purposes, and then lay down a bed of gravel in the trench. This will support our footer drain, which is typically a 4" perforated pipe. Oftentimes a larger 12" culvert pipe will be inserted vertically in one end of the trench. This will act as our sump pump well. The pipe will rise vertically to the surface of the existing grade, allowing access to the pump for future maintenance as necessary. A hole is drilled in the pump well, and the 4" perforated pipe is inserted into it. Once complete, the drainpipe is covered completely with about 2"-4" of gravel.
3. Sump Pump - Once the drain and pump well are in place, a sump pump with an attached extension pipe, long enough to reach the surface, is lowered into the culvert pipe/pump well. It's important to put the sump pump in at this point because during the next step, the surface of the exterior wall will be cleaned with water, and we need a way to pump that water out of the trench.
4. Cleaning and Tuckpointing - The wall is cleaned with a hose or high-powered pressure washer. Then any holes or broken blocks are tuckpointed with cement, to fill any voids where water may be flowing into the foundation.
5. Rubberized Coating - After the surface of the foundation wall has dried, and any cement tuckpointing has cured, it's time for the rubberized coating. Depending on the product used, this can either be sprayed on the wall or rolled and brushed on. It's important to make sure the coating covers the entire surface and is applied up above the final grade.
6. Backfill - Once the rubberized coating has dried, it is now time to backfill. Care should be taken not to scratch or damage the new coating with heavy rocks or the tools when backfilling.
7. Final Plumbing - After the final grade has been reached, the sump pump drain will need to be tied into existing downspouts, or routed to a runoff area. An access cap is then placed over the pump well.
8. Replace Landscaping - At this point, the trenched area should be tamped down and any landscaping that was moved returned to its original location, and the area cleaned up.

Why Use A-1 for Exterior Basement Waterproofing?

• Highly trained crew, with years of experience
• Expertise for the right products and techniques for your specific needs
• Multi-year warranty on every crawlspace encapsulation job
• No job is too large or too small
• Locally Owned and Operated
• Supported by our National A-1 Franchise Network
• A-1 is a fully insured contractor