Waterproofing a foundation is one of the most significant investments a homeowner can make to protect their property. Whether dealing with frequent rain or high water tables, keeping your foundation dry is essential to maintaining the integrity of your home.
This post covers the costs of waterproofing a foundation’s exterior, providing a detailed look at different methods, pricing, and factors influencing the final expense. By understanding these elements, you’ll be better equipped to choose the right approach for your home’s needs.
Let’s get straight to the point.
Waterproofing a foundation’s exterior typically costs between $3,000 and $15,000, depending on the size and complexity of the project. Smaller jobs may cost $3,000 to $5,000, while larger or complex projects can range from $10,000 to $15,000.
Cost factors affect foundation size, depth, waterproofing method, foundation condition, and labour costs. Common methods include cementitious coatings ($1,000 to $1,500), exterior membranes ($5,000 to $15,000), and French drains ($100 to $250 per meter).
The Costs Of Exterior Foundation Waterproofing
The cost of waterproofing the exterior of a foundation generally ranges between $3,000 and $15,000.
The cost varies widely depending on the job size, the materials used, and the complexity of the work involved. For a typical home, the national average cost is around $5,500 to $10,000.
Small Projects: $3,000 To $5,000
Smaller homes or properties with minor waterproofing needs typically cost between $3,000 and $5,000.
These projects often involve simple sealing work around the foundation and do not require extensive excavation. Since the work is minimal, labour and material costs are lower.
Additional steps, such as fixing small cracks or applying waterproof coatings, may be included in some cases. These smaller projects are ideal for homeowners looking to prevent future water damage without major construction work.
Average Projects: $7,000 To $10,000
Medium-sized homes or typical waterproofing needs range from $7,000 to $10,000. In this price range, the work often involves sealing the foundation and installing extra drainage solutions, such as sump pumps or French drains.
Excavation may be required to expose and waterproof the foundation. This scope of work is ideal for homes with basements around 1,000 square feet, ensuring that water is properly diverted away from the structure to prevent leaks and long-term damage.
Large Or Complex Projects: $10,000 To $15,000
Large or more complicated waterproofing projects cost between $10,000 and $15,000. This price range is common for larger homes or those with severe water issues that require significant excavation and drainage work.
These projects often involve deep excavation, repairing damaged foundations, or installing extensive drainage systems, like French drains or external sump pumps. Due to the complexity, labour and material costs are higher, and the work may include additional waterproofing measures, such as reinforcing basement walls to ensure full protection.
Factors Affecting The Cost Of Waterproofing A Foundation Exterior
Several factors can influence the overall cost of waterproofing a foundation exterior.
The complexity and size of the project, the method used, and the condition of your foundation all affect the final price. Below are the key factors that will affect your costs.
Foundation Size
The size of your foundation is one of the biggest factors in determining cost. Larger foundations will require more materials and labour, increasing the overall price.
- Larger foundation = more materials and labour
- Smaller foundation = lower overall cost
Depth Of The Foundation
The depth of your foundation also impacts costs. Deeper foundations require more excavation, which increases the labour and time required for the project.
- Shallow foundations (up to 4 feet): Less expensive, less labour
- Deep foundations (more than 4 feet): More expensive due to the need for deeper excavation and possibly window wells
Type Of Waterproofing Method
Different waterproofing methods have varying costs, with some techniques being more affordable than others. Here’s a breakdown of the most common methods:
- Cementitious Waterproofing: $1,000 to $1,500 – A simple method applied to the exterior of the foundation.
- Waterproof Membranes: Up to $15,000 – Highly effective but costly, requiring excavation and expert installation.
- Weeping Tiles (French Drains): $100 to $250 per metre – Installed to direct water away from the foundation.
- Silicate Concrete Sealers: $3 to $9 per square foot—This cost-effective option penetrates concrete and forms a barrier.
Condition Of The Foundation
The foundation’s condition also plays a big role in the overall cost. If there are cracks, holes, or damage, these must be repaired before waterproofing can begin, adding to the cost.
- Foundation repairs: Cracks and structural damage will need fixing, which can add thousands to the project.
- Good condition: Costs will be lower if the foundation is in good shape.
Labour Costs
Labour costs vary based on location. In areas with a higher cost of living, expect to pay more for professional waterproofing services. Labour can account for a large portion of the overall cost.
- Urban areas: Higher labour costs due to increased demand and cost of living.
- Rural areas: Typically lower labour costs.
Location And Water Table
The location of your home and the water table in your area can also impact the price. Homes in areas with high water tables or frequent flooding may require more extensive waterproofing solutions.
- High water table areas: expensive due to the increased need for drainage systems.
- Low water table areas: Less costly as less extensive measures may be needed.
Excavation Requirements
Excavation around the foundation is usually required for exterior waterproofing. Excavation costs can rise if your home has a deep foundation or access to the foundation is difficult.
- Shallow foundations: Lower excavation costs.
- Deep or complex foundations: Higher excavation costs, especially if heavy machinery is required.
Typical Methods And Their Costs
Different waterproofing methods have different price tags. Your chosen method depends on your foundation’s needs, soil type, and climate conditions.
Cementitious Waterproofing
This method involves applying a cement-based coating to the foundation’s exterior. It’s affordable and effective for minor water issues but might not be sufficient for homes in areas with heavy rainfall or high water tables.
- Cost: $1,000 to $1,500
- Best for: Smaller jobs or homes in drier climates.
Exterior Membranes
These membranes, typically made from rubberised asphalt, are applied to the exterior foundation walls to create a waterproof barrier. They’re one of the most effective but also one of the more expensive options.
- Cost: $5,000 to $15,000
- Best for: Homes in areas with frequent rain or high water tables.
Weeping Tile (French Drain) Systems
Weeping tile systems, or French drains, direct water away from your foundation and prevent water buildup.
- Cost: $100 to $250 per metre
- Best for: Homes prone to flooding or in areas with poor drainage.
Silicate Concrete Sealers
Silicate sealers penetrate the concrete and form a water-resistant barrier. This cost-effective method might not be suitable for areas with significant water pressure.
- Cost: $3 to $9 per square foot
- Best for: Budget-conscious homeowners who need basic waterproofing.
Conclusion
Waterproofing the exterior of your foundation is a critical investment in protecting your home from water damage and maintaining its structural integrity. While the costs can vary significantly depending on factors such as foundation size, depth, the waterproofing method chosen, and labour expenses, it’s clear that the long-term benefits far outweigh the initial outlay.
Whether you opt for a budget-friendly approach like silicate sealers or a more comprehensive solution like exterior membranes or French drains, ensuring your foundation is secure against water intrusion is essential to prevent costly future repairs. By carefully assessing your home’s needs and considering the factors outlined in this post, you’ll be better prepared to choose the right waterproofing method and protect your home for years.
FAQs About Waterproofing
How Do You Waterproof The Outside Of A Foundation?
- 1 – Excavate the ground around the perimeter of the foundations.
- 2 – Seal all cracks in the concrete.
- 3 – Attach a waterproofing membrane to the outside of the foundation.
- 4 – Backfill the trench dug around the foundations.
How Much Is A Waterproof Membrane?
Bathroom waterproofing can cost as little as $40 per square metre, but that is the low end of the scale. Generally, expect to pay between $500 and $750 to completely waterproof an average-sized bathroom.
Should You Waterproof Your Foundation?
The best waterproofing for concrete walls protects the foundation from soil and liquid moisture. To optimize protection, waterproofing systems should be applied to all foundation walls with earth on one side and usable space on the other (including crawl spaces).
Can You DIY Waterproofing?
DIY options do exist, but there are some caveats. In Queensland and NSW, you can only do your waterproofing if you’re licensed to do so (i.e. the work must be done by someone with a licence).
How Long Do Waterproof Membranes Last?
Ten Years: While basic waterproofing membranes should last at least ten years, they can last much longer, given the right choice and circumstances. Conversely, poor-quality waterproofing will rarely last the distance.
