Foundation Waterproofing Retrofit
A foundation waterproofing retrofit refers to the process of applying waterproofing measures to an existing foundation, as opposed to implementing these measures during the initial construction of a structure. Foundations are critical components of buildings, ensuring stability and structural integrity. Protecting them from moisture and water damage is crucial for the longevity of the structure and the health of its occupants.
Here's a deeper look into foundation waterproofing retrofit:
Reasons for a Foundation Waterproofing Retrofit:
Existing Water Issues
Homeowners might experience a wet basement, signs of mold growth, or visible water infiltration, suggesting that the original waterproofing measures (if any were applied) have failed or become less effective over time.
Structural Concerns
Continuous water exposure can lead to the deterioration of foundation materials, compromising the building's structural integrity.
Health Concerns
Moist environments within a home can lead to mold and mildew growth, which can cause or exacerbate respiratory issues among occupants.
Property Value
A well-maintained, dry basement can enhance property value. Potential buyers typically prefer homes without basement water issues.
Methods of Foundation Waterproofing Retrofit
Exterior Waterproofing
This involves excavating around the home's foundation to install or replace a waterproof membrane on the exterior wall. While this is the most effective method since it stops water at its source, it's also the most invasive and can be quite costly.
Considerations
When considering a foundation waterproofing retrofit, homeowners should:
Assess the extent of the issue
Sometimes, signs of moisture may be due to other factors, like condensation.
Hire a professional
Addressing foundation water issues is typically not a DIY project. A professional can accurately diagnose the problem and recommend appropriate solutions.
Think long-term
While some measures (like sealants) can offer temporary relief, addressing the root cause ensures a more permanent solution and can prevent more costly repairs down the line.
In conclusion, a foundation waterproofing retrofit is a crucial step in ensuring the structural integrity of a building and the well-being of its occupants. Given the potential costs associated with water damage and the loss of property value, proactive waterproofing measures can be a wise investment.
Why Waterproofing Retrofits?
Some of the oldest houses around us were built at the beginning of the 20th century. Houses built through the 70’s didn’t have any waterproofing, and the waterproofing systems for houses built even into the 90’s was mediocre.
And the modern waterproofing systems are excellent. So a common project for us is to excavate the perimeter of the foundation and install a new waterproofing system and footing drain.
Excavation
This type of project - and the related expenses - are often driven by the porches, hardscaping and landscaping around the house. Too much disruption due to excavation can make the project expensive, which is why an interior drain can be an attractive choice.
But the process is not difficult. A 3’ wide path is excavated around the perimeter of the foundation. Dirt is held onsite when possible, and when it is appropriate for use as foundation fill. ( It should be free draining).
Waterproofing
The waterproofing process is the same as it is with new construction, and involves the application of a sprayed membrane and drainage course.
But first the foundation must be prepared. It gets pressure washed, imperfections are sacked, and any large issues evaluated with the homeowner.
Footing Drains
After waterproofing, the footing drain is put in. A footing drain is constructed like a french drain, except it is built next to the footer. 4” perforated PVC pipe is surrounded in clean 1.5” rock and the whole thing is wrapped in drain fabric. This is installed with 0% slope.
Downspout Drains
The excavation usually means that the downspout drains need to be redone. The system can be installed near the footing grade or closer to the surface, but unlike footing drains, should be be installed with slope, often a minimum of 2%.
The downspout drains and footing drains need to be separate. We get called out to a lot of jobs because of this mistake. The footing drains need to act as a drain. But if you pump a bunch of water into them from the roof, they act as a dispersion trench, flooding the foundation.
The two systems can be tied together to share a discharge line past the house. After that, the city and each property will have their requirements about what needs to be done with the stormwater.
Backfill and Grading
The excavated soil is usually used to backfill - it is expensive to move earth. But it should be free draining. The backfill should be compacted in lifts, a time consuming process that is part of doing the job correctly.
It is important that the earth slope away from the house. This can be difficult on all sites, and sometimes requires a combination of grading and drainage to function correctly.
Hardscapes and Landscapes
The final part of the project is to re-install the landscaping and hardscaping that was taken out. This is often left to other contractors, but we’re happy to help when the customer would prefer that we do the work.
Typical Services
Substrate Preparations
Waterproofing Membranes
Drain boards and protective coverings
Filter Fabric
Insulation