Exterior Waterproofing Technique
1. Excavate the suggested perimeter structure.
- Dig down to the base of the foundation.
2. Inspect structure for cracks.
- Clean wall.
- Verify areas of cracks that are causing water to seep into your home.
- Fix any crack/holes.
3. Apply sealer to the wall (Sealant).
- The propose of the sealer is to close all possible pores/invisible to the naked eyes or any crack that wasn’t able to be fixed using hydraulic cement.
4. Membrane Installation
- Do not use tar because when exposed to air, it dry-out and become very brittle thus easy to crack hence re-leak happens
- Bituminous Waterproofing Membrane
- Compose of petroleum-based asphalt material.
- Consider the most commonly used exterior membrane.
- Highly resistant to moisture.
- Apply to the wall using trowel and rollers.
- A fiberglass mesh material is usually used between applications.
- Over time this type of membrane becomes brittle because it exposes to the environment causing it to dry-out.
- Liquid Waterproofing Membrane
- More often used for interior waterproofing because of its low odor and very easy to apply.
- Apply to the wall using a paintbrush.
- Extremely effective to use in any environment (hot or cold).
- Unlike Bitumen, it won’t crack or shrink.
- Elastomeric Waterproofing Membrane
- Considered to be a “lifetime waterproofing” technique because it’s composed of polyurethane.
- Apply to the wall using paintbrush and/or rollers.
- Mainly used for exterior waterproofing.
- Comparably expensive.
- Crystalline Waterproofing Membrane aka Capillary Waterproofing System
- Almost entirely use for interior waterproofing.
- The liquid penetrates through the concrete wall to form crystals and seal the capillaries inside.
- This product permeates through the wall to forms a chemical reaction with the line in the concrete thus preventing moisture from penetrating.
- less expensive.
- Easy to apply but several applications are necessary.
5. Apply Drainage Mat
- This dimpled material must create air gaps between the newly treated wall and itself. These air gaps serve as channels for moisture to diverse to the drainage system/weeping tile.
6. Installing Weeping Tile / Drain Tile / Perimeter Tile
- Weeping tiles are usually 4” diameter wide perforated pipe wrap with thin cloth/sock.
- It’s a good idea to install cleanup valves for maintenance purposes only.
- The proper slope of weeping tile is essential so water can flow easily away from the structure.
- Sometimes 4” corrugated pipes are used that are wrap with landscaping fabric.
7. Back-filled excavated area.
- cover weeping tile with crush rocks.
- Add a layer of fabric to the excavated soil. The soil must be compacted ever few inches depending on the type of soil.