What is Frost Wall? Types and Uses of Frost Walls – In freezing temperature climates, frost walls or frost protected walls are used to keep the soil beneath the building from freezing and protect the foundations. The different types of frost walls, as well as their requirements and applications, are discussed.
Frosting is a significant problem for building structures in colder climates. On the building foundation, these negative effects are more pronounced and visible.
Any damage to the building foundation will compromise the structure’s overall stability. The most common solution in areas where frosting is a persistent problem is to build a deep foundation that will be laid over a footing level well below the frost line.
As a result, constructing buildings and structural elements in harsh climates is a difficult task. A single factor that influences the construction is the temperature characteristics of the building materials used.
In colder climates, concrete placement and mixing causes the mix to contract. Internal stresses will result from the concrete contractions.
Internal strain will be extreme if these contraction and internal stress issues are not taken seriously. Internal strain accumulation poses a significant threat to the structure’s structural integrity and serviceability.
Why Frost-Protected Walls are Required?
The purpose of a frost-protected wall is to keep the soil around the building from freezing in extremely cold temperatures. To prevent the soil from freezing, a type of heat conversion is used to transfer heat from the building to the soil beneath it.
The soil matrix, as we know from basic soil mechanics, is made up of voids that are filled with water and air. These soil voids will be filled with air in dry soil. In saturated soils, the voids will be filled with water, which will freeze when the temperature drops below freezing. When water is converted to ice, the volume of water in a void expands.
Water is mostly present in the soils beneath the foundation. If the structure is built in a colder climate, these waters will freeze. Any drop in temperature causes the ice to melt into water. As a result, a freezing and thawing procedure is required.
With the conversion of water in soil to ice, this frost heaving phenomenon will become more common. An ice lens is a collection of frozen ice crystals in the soil. The nearby soil mixture will be heavily pushed by these ice lenses. Any structure built on top of such expanded soil will be pushed upward.
As a result, the only way to avoid such problems is to develop a method of preventing soil freezing. The frost wall is a one-of-a-kind technique that is widely used for this purpose.
What is Frost Wall?
A frost wall is an insulated wall that is built around the foundation’s perimeter. These are built below the frost line and deep underground. The foundation will not be subjected to upward pressure from the frost heave process because the frost wall is placed beneath the soil.
The term frost wall can also refer to walls that are built above ground level in the interior of a building structure.
As a result, this will act as insulation, keeping the interior of the building warm. These frost walls also collect heat from the structure, preventing freezing and other problems in the surrounding soil.
Frost Wall Types
There are various types of frost walls that can be constructed depending on the load, temperature, and building features. There are one of them:
- Load Bearing Frost Walls
- Non-Load Bearing Frost Walls
Load Bearing Frost Walls
This frost wall construction will shift the foundation’s responsibility to the frost wall. By being built beneath the soil’s surface, the frost wall will act as a foundation wall.
This will be clearly constructed below the area’s frost line. Extreme weather conditions necessitate the construction of frost walls of this type (freezing temperatures).
Non–Load Bearing Frost Walls
These frost walls are built in the same way that an insulating wall is. This is used in homes that aren’t properly insulated. Inside the building, these insulated non-load bearing walls will be built.
Frost walls that are not load bearing help to keep heat from escaping through the foundation. The constructed interior frost wall must not come into contact with the exterior wall. When constructing the same, extra caution should be exercised.
Between the two walls, there is a gap. It is also recommended that a barrier be installed to prevent moisture from becoming ice within the wall structure.
Frost Wall Construction Requirements
The frost wall will perform better if all of the structural elements that go with it have the required properties.
The following are some of the basic characteristics related to its requirements:
- To avoid any open gaps, the basement wall constructed beneath the wall must be patched. The most common material used to build these basement walls is cinder blocks. Brick fillers can be used to fill in the gaps.
- If your basement walls are made of concrete, you’ll need to use a paint sealer to get rid of any cracks. There are special paints on the market that will help prevent moisture from penetrating the basement.
- All structural elements must be constructed with the primary goal of preventing moisture intrusion.
Application of Frost Wall
The workings and construction of a frost wall for preventing the freezing of shallow foundations and non-heated buildings are described below.
Frost Wall for protection of Shallow Foundation
Non-bearing frost walls are frost walls that are built with the intention of protecting a shallow foundation. When frost wall construction as a deep foundation is not feasible for the area or does not provide any economic benefit, this type is used.
The frost wall is built by leaving a specified gap between the foundation and the frost wall, as per the constructor’s recommendation. This is set up in such a way that the heat is not lost to the soil.
These types of frost wall construction are built around the foundation to efficiently warm up the heat radiated from the building.
On the exterior of the foundation, a rigid foam insulation is installed vertically, and on the basement of the foundation, a rigid foam insulation is installed horizontally. The construction of these insulation allows heat generated inside the building to move down into the soil, preventing it from freezing.
Frost Wall for Non-Heated Buildings
Only if the building constructed is a heated building does the frost wall described above provide warmth for the building. This type of frost wall will not work in a non-heated structure.
A solution to this problem is to design a horizontal layer that is placed beneath the entire building’s foundation. This horizontal layer must also extend outward from the building area. There is no provision for vertical insulation.
The insulation is placed on top of the gravel layer. As a result, the warmth will be trapped in the soil, preventing it from freezing.
Er. Mukesh Kumar is Editor in Chief and Co-Funder at ProCivilEngineer.com Civil Engineering Website. Mukesh Kumar is a Bachelor in Civil Engineering From MIT. He has work experience in Highway Construction, Bridge Construction, Railway Steel Girder work, Under box culvert construction, Retaining wall construction. He was a lecturer in a Engineering college for more than 6 years.