Basements are a great way to add extra space to a home. They can be used for storage, as a laundry area, a workshop, or even turned into a living space. However, before a basement is built, it requires a strong and reliable foundation to support the entire structure.
A basement foundation not only supports the building but also creates an additional underground floor. Understanding how basement foundations work, their types, and their benefits can help homeowners make better choices when building or renovating their homes.
What is a Basement Foundation?
A basement foundation is a foundation type that goes underneath the ground floor of your home. This provides support to the building as well as additional storage, living areas, or housing mechanical systems. Typically, these foundations are constructed with concrete block walls that cover the entire perimeter of the building. The floor is also constructed from concrete slabs to uniformly distribute the building’s weight across the soil.
Basement foundations serve two main purposes: they provide structural support to the building and create extra space for storage or as living quarters. Basement foundations are more challenging to construct than standard foundations and require additional time. Heavy-duty equipment, like cranes, excavators, and forklifts, is often required to dig the soil to lay the foundation.
Despite their differences in depth and construction timeline with traditional foundations, the standard roadmap for their construction procedure remains the same.
Key Characteristics of Basement Foundations
Underground Structure: A basement foundation is constructed several meters below the ground floor. It provides additional space, forming a new floor.
Reinforced Concrete: These are constructed using concrete blocks or poured concrete to achieve better strength and durability.
Weight Distribution: Due to the placement of wide concrete slabs and blocks under the building, the total weight is evenly distributed, providing additional stability.
Insulation: Basements are usually built in regions with harsh, cold weather conditions. This underground structure keeps the living space warm and insulated.
Drainage: For the houseâs drainage purposes, water pumps and a proper drain pipeline are installed to prevent flooding in the basement.
What are the Different Types of Basement Foundations?
There are several types of basement foundations, but the most commonly used in the construction sector are:
Full Basement Foundations
Full basement foundations are the most common and traditional way of building a basement. The perimeter of the full basement foundation encircles the whole structure area. Due to this property, it can be used for various purposes, as it provides ample space for both storage and living.
Construction of a full basement foundation starts with excavating the soil to dig a deep hole, enough to hold the full-size basement. Due to their underground structure, full basements typically lack proper ventilation and windows.
Additionally, they provide easy access to home heating, plumbing, and electric systems. Full basements are expensive to build and require a significant amount of time for their completion.
Partial Basement Foundation
A partial basement is a type of basement that only covers a specific section of the homeâs footprint rather than covering the entire house. It is usually half the size of a full basement foundation, but it has the same depth and style as a full-size basement.
Partial basements are categorised into two types:
- Underground Basements
- Daylight Basements
Underground basements are fully constructed beneath the ground floor. They donât have access to natural sunlight. In contrast, daylight basements are designed to have access to the sunlight through properly placed windows. Because daylight basements receive more natural light, they are easier to transform into a proper living space.
Slab-On-Grade Foundations
Slab-on-Grade foundations involve pouring a single, thick concrete slab directly onto the ground. It is easy to install and is a cheaper alternative to other basement foundations.
The slab is usually reinforced with steel rebar or wires to enhance its strength and longevity. Slab-on-grade foundation is cost-effective and quick to build, as it requires minimal or no excavation.
Walk-Out Basement Foundations
A walk-out basement foundation is a specialised form of basement foundation designed for houses and buildings located on uneven ground. Unlike traditional basement designs, walk-out basements have at least one wall that is slightly above ground level for the installation of a full window or door. This allows these basements to have direct access to the outside.
This foundation type is generally built using concrete blocks reinforced with steel, supported by a footing to support the exposed wall. Due to their unusual structure, walk-out foundations require proper waterproofing, advanced design, and an effective drainage system.
Crawl Space Foundations
Crawl space foundations are not technically a basement foundation, but are quite similar in construction and some characteristics. A crawl foundation is a shallow foundation that raises the house several feet above the ground, resulting in a small, narrow space between the house and the ground.
These foundations are built in areas prone to high water tables and unstable soil conditions. These are less expensive to build and require less time to construct. The crawl space offers limited space and accessibility.
Benefits of Basement Foundations
Stability and Durability: Basement foundations evenly spread the building’s entire weight onto the ground. This makes the structure more stable and resistant to soil movement. Foundations built with reinforced concrete provide durability and stability.
Increase Property Value: These foundations provide extra living and storage space without altering the homeâs infrastructure. This feature makes the property more desirable and expensive.
Storage and Living Space: A properly designed full or partial basement has ample storage for different items. It can also serve as a suitable living space if furnished appropriately.
Storm Shelter: In regions of extreme weather conditions, where natural disasters are more likely to occur, a well-designed basement provides secure shelter to you and your loved ones.
Basement Foundation Construction: Step-by-Step Process
Constructing a basement foundation is a complex process that requires precision, proper planning, and specialised equipment. While each type of foundation has its own specific construction method, the general roadmap is the same for all types.
Site Preparation
It starts with a survey of the land and marking the specific footprints for the foundations. After proper marking, excavate the soil to the required depth with proper machinery while making sure the slope is properly aligned to prevent water drainage issues.
Footing Installation
It starts with pouring a concrete footing at the maximum depth of the foundation. After pouring, the concrete is reinforced with the steel rebars for additional strength and support. After reinforcing the footing, allow the concrete to cure properly before moving forward with the construction.
Wall Construction
Once the footing is cured, the foundation walls are constructed. They can be built by pouring the concrete into the frames or by adding pre-built concrete blocks vertically to resist soil pressure and provide additional support.
Waterproofing and Drainage
After the construction of the walls, a waterproof membrane or layer is added to the exterior surface of the walls. Drainage pipes are installed at the base of the walls to carry water out. This step is necessary to prevent any leaks and future structural damage.
Final Grading and Backfilling
Once the foundations are constructed, the soil is carefully backfilled around the exterior of the walls to protect the waterproofing layer. This must be performed by professionals to avoid any damage to the foundations. After backfilling, the soil is precisely shaped through the grading process to create slopes and elevations across the site.
Key Considerations in Basement Foundation Design
Building the perfect basement foundation with the appropriate design and measurements is a lot of responsibility. Before designing the foundation, the contractor needs to assess the site for:
- Waterlogged ground
- Soil conditions
- Cost and timeline
- Effect of construction
How to Choose the Right Basement Foundation?
The choice of the right basement foundation depends primarily on the site location and local weather conditions. The key considerations for choosing the right basement foundation are:
- Soil type and water level
- Local weather
- Budget
- Desired outcome
- Local construction laws
If you have already hired a professional construction contractor, following their recommendation is also the best choice.
General Tips for Basement Foundation Repairs
The basement foundations can develop some issues over time. These can be due to water damage, soil movement, or natural disasters. Knowing basic repair and maintenance tips can save you a lot of time and money. Some common practical tips are:
Proper Inspection
Inspect your basement regularly for any damage and leaks. The sooner you recognise the situation, the easier it becomes to fix the damage.
Address Water Damage First
The most common problem with a foundation is water damage. If you spot any issues with the waterproofing membrane or drainage pipes, fix them on an emergency basis, as they can be problematic if left unresolved.
Choosing the Right Repair Method
Not all damages and problems require the same repair method. Various techniques and tools are applied depending on the damage type.
Hire Professionals
Fixing structural or water damage yourself may seem doable, but sometimes it can be dangerous and make the damage worse. Hiring professionals is always recommended for all repairs and fixes.
Donât Delay Repairs
Foundation problems can worsen with the passage of time. Resolving issues promptly not only saves money but also prevents significant damage.
Conclusion
A basement foundation isnât just the base of your home it ensures the entire structureâs safety and stability. It also provides extra space for storage, utilities, or a potential living area. Selecting the appropriate type of basement foundation and ensuring proper construction and maintenance can prevent future issues and increase your homeâs value.
With proper planning and upkeep, your basement foundation can remain durable and functional for many years.