How to Waterproof Exterior Foundation Walls?
An exterior foundation wall is a vertical structure that forms the underground perimeter of a building.
Waterproofing an exterior foundation wall is applying a waterproof membrane on the exterior foundation wall in order to prevent water penetration into the basement inside. Waterproofing exterior walls prevents water infiltration, protects structural integrity, avoids mold and mildew growth, improves indoor air quality and prevents pest infestation.
You will need suitable waterproofing materials and tools for foundation exterior waterproofing. You should follow the below steps for the process.
9 Steps to waterproof exterior foundation walls
- Excavate a trench along the foundation.
- Clean the exterior foundation walls.
- Inspect and repair the exterior foundation wall.
- Apply primer to the foundation wall.
- Apply a waterproof membrane
- Install drainage board
- Install French drain system.
- Backfill the dug trench.
- Grading the ground
After you waterproof the exterior foundation wall you should avoid plantation near the foundation walls, level the soil properly near the foundation, insulate the foundation, use a dimpled drainage mat and do regular inspection of the waterproof layer.
If you do not protect the exterior foundation wall it will be damaged due to frost heave, soil settlements, root damage, and improper backfilling. In order to proper water protection. You should waterproof both interior and exterior waterproofing.
9 Steps to Waterproof Exterior Foundation Walls
You can waterproof an exterior foundation wall by following the 9 steps
- Excavate a trench along the foundation.
- Clean the exterior foundation walls.
- Inspect and repair the exterior foundation wall.
- Apply primer to the foundation wall.
- Apply a waterproof membrane
- Install drainage board
- Install French drain system.
- Backfill the dug trench.
- Grading the ground
1. Excavate a trench along the foundation.
Excavating a trench along the foundation allows access to the foundation wall for cleaning, applying waterproofing materials and installing a drainage system. The typical depth of a trench is 4-8 feet deep, and the width is around 1.5 -2 feet.
You can use a shovel, pickaxe, rake, wheelbarrow and mini excavator to excavate a trench. The time taken to excavate a trench depends on the size of the trench, but typically around 2 - 4 days.
2. Clean the exterior foundation walls.
By cleaning the exterior foundation walls, you can identify the cracks and gaps properly and a clean the surface for sealants to adhere properly. You can use a garden hose with a nozzle, stiff bristle brush, TSP, drop clothes, safety glasses to clean the exterior foundation walls.
The time taken for the cleaning will depend on the size of the basement wall. A small basement of around 800 sq ft will need 1-2 hours, while a large basement of 1500 sq ft will need 2- 4 hours.
3. Inspect and repair the exterior foundation wall.
You can identify minor cracks and gaps by inspecting and repairing the exterior foundation walls. Repairing them before waterproofing will make the waterproofing membrane long lasting without getting deteriorated.
You can use flashlights, a straightedge, a small hammer, tape measure, a crack gauge to inspect and hammer a drill, a chisel and hammer, an angle grinder, a paint scraper, a caulk gun and a masonry brush to repair. The time taken to inspect and repair will be 1 - 2 days.
4. Apply primer to the foundation wall.
Applying primer to the foundation wall improves adhesion and creates a better bond between the foundation wall and the waterproofing membrane.
You can apply the primer with a stiff brush, a garden hose with a nozzle, a scraper, a drop cloth, a paint roller, a concrete surface cleaner, or a masonry primer.
5. Apply a waterproof membrane
A waterproofing membrane is a barrier against water penetration into the basement.
You can use a stiff brush, garden hose with a nozzle, utility knife tape, squeegee and caulking as tools and masonry surface cleaner, masonry primer, and a sheet waterproofing membrane or a liquid waterproofing membrane as products to apply a primer to the exterior foundation walls.
6. Install drainage board
Installing a drainage board will protect the waterproofing membrane by promoting water drainage, relieving pressure and controlling moisture.
You can use a utility knife, tape, jab saw, hammer drill, landscape staples as tools and drainage board, landscape fabric, waterproofing membrane fasteners and caulk as products when installing drainage board.
7. Install French drain system.
Installing the French drain system will protect the waterproofing membrane by removing the water from the basement.
You can use a utility knife, hammer drill, jab saw, and landscape staples as tools and perforated drain pipe, filter fabric, and crushed stone as products when installing a french drain. Installing a French durian will take 2 - 5 days, depending on the size.
8. Backfill the dug trench.
Backfilling the dug trench will prevent the foundation from bowing or cracking due to pressure imbalance and protect the waterproofing membrane from damage caused by landscaping.
You can use a shovel, rake, or tamper as tools and excavated spill, clean fill material, and landscape fabric as products for backfilling.
9. Grading the ground
By grading the ground, water will be directed away from the foundation protecting the basement. You can use shovel, rake, level, and tamper as tools for grading.
What is an Exterior Foundation Wall?
An exterior foundation wall is a vertical structure that forms the underground perimeter of a building. It is made of porosity materials such as concrete, brick, and stone. It helps to prevent water leaking, improve structural integrity, increase the useable space of the basement, improve energy efficiency, and prevent water damage in the foundation.
Before you start exterior foundation wall, you should know all about foundation waterproofing. You can you these waterproofing methods to waterproof the exterior foundation.
What are the 5 Advantages of Waterproofing Exterior Foundation Walls?
5 Advantages of Waterproofing Exterior Foundation Walls
- Prevent water infiltration into the basement
- Protect structural integrity
- Avoid mold and mildew growth
- Improve indoor air quality
- Prevent pest infestation
1. Prevent water infiltration into the basement
Exterior foundation wall waterproofing helps to prevent water infiltration into the basement. It helps to avoid basement flooding and condensation, which can cause damage to the basement components and structure poorly.
2. Protect structural integrity
Exterior foundation wall waterproofing helps to seal the cracks in the wall and prevent the water from leaking into the basement due to hydrostatic pressure. It helps to protect the structure from damping, paint peeling, wetting, rotting, and decaying the materials.
3. Avoid mold and mildew growth
Exterior foundation wall waterproofing avoids water seepage and dampness of the interior walls. It helps to prevent dampening the interior walls and avoid mold and mildew growth in the basement. As well as exterior foundation waterproofing helps to control the humidity in the basement. This helps to reduce mold and mildew growth automatically.
4. Improve indoor air quality
Exterior foundation walls waterproofing improve the indoor air quality by preventing mold growth and moisture-related issues directly. Therefore, harmful gases and mold will not enter the house.
5. Prevent pest infestation
Exterior foundation wall waterproofing prevents dampness inside the basement. It helps to prevent the pest infestation.
What Materials Need to Waterproof Exterior Foundation Walls?
- Safety gloves
- Safety glasses
- Excavator
- Shovel/rake/wheelbarrow
- Hammer or a drill
- Garden hose with sprayer nozzle
- Paint roller with the extension pole
- Utility knife
- Caulking gun
- Tape measure
How to Protect Waterproof Exterior Foundation Wall?
These are the 5 helpful ways to protect waterproof exterior foundation wall.
- Avoid plantation near the foundation walls: Do not plant trees or shrubs near the foundation. Roots of trees can damage the waterproofing membrane.
- Proper soil levelling near the foundation: Maintain the soil level around the foundation at least 6 inches below the bottom of the siding. This prevents water from pooling near the foundation.
- Insulate the foundation: Foundation insulators can reduce heat transfer and control basement temperature. You should use insulation which is compatible with a waterproofing membrane.
- Use a dimpled drainage mat: A dimpled drainage mat will provide extra space between the waterproofing membrane and the backfill. This extra layer of drainage space protects the waterproofing membrane from punctures by a rock in the backfill.
- Regular inspection: Regular inspection of the waterproofing membrane treats the gaps and cracks in the waterproofing membrane.
How to Damage a Waterproof Exterior Foundation Walls?
These are the 4 ways to damage waterproof exterior foundation walls.
- Frost heave: A waterproof exterior foundation wall can be damaged due to frost heave. Frost heave can occur due to freezing and expansion of water in the soil around the foundation. Frost heave causes cracks in the foundation walls and floor slab, misaligned doors and water leakage, daming the waterproofing membrane.
- Soil settlement: A waterproof exterior foundation wall can be damaged by the soil settlements near the wall. Soil settlement occurs due to poor soil compaction during construction, vibration from near by construction and organic matter decomposition. Soil settlement causes uneven floors, cracks in the floor and water leakage, damaging the waterproofing membrane.
- Root damage: A waterproof exterior foundation wall can be damaged by the roots. Root damages occur due to growing shrubs or trees close to the foundation walls. Root damage can cause cracks in the foundation, gaps, water leakage, and movement in the foundation.
- Improper backfilling: A waterproof exterior foundation wall can be damaged due to improper back filling. Improper backfilling is caused by to use of the wrong material for the backfilling. Improper backfilling will cause pressure on foundation walls, causing pressure, water leaks, increased moisture levels and damage to the waterproofing membrane.
Should You Waterproof Both Interior and Exterior Foundation Walls?
Yes, you should waterproof both interior and exterior foundation walls in order to prevent water from leaking into the basement.
You should waterproof exterior foundation walls in order to prevent water damage cracks, reduce hydrostatic pressure, improve indoor air quality, and increase property value.
When you waterproof interior foundation walls, you can prevent basement water intrusion, create a healthy environment, and control humidity and condensation successfully.