And the distinction between them is critical for properly safeguarding a building’s foundation.
Here is a description of both waterproofing and damp proofing, along with an explanation of why it’s crucial to understand the distinction between the two.
Let’s Dive In!!!
What is the difference between damp proofing and waterproofing?
The two terms damp proofing and waterproofing are not interchangeable. While waterproofing keeps out both moisture and liquid water, damp proofing is designed to keep out soil moisture.
Buildings have been damp proofed for many years; this process was previously referred to incorrectly as waterproofing. The situations that call for damp proofing or waterproofing are listed in Section R406 of the International Residential Code (IRC).
“That retain soil and enclose internal spaces and floors below grade shall be damp proofed from the top of the footing to the finished grade,” states the building code.
The IRC then lists a list of acceptable materials, which includes cement with an acrylic modification and bituminous coating. Only sites with a high water table or other recognized severe soil-water conditions are needed to have waterproofing, according to the IRC.
A coating known as “damp proofing,” which is typically asphalt-based, is applied manually or with a sprayer to the outside of a wall. It is still a viable kind of treatment in many circumstances, although being less typically advised in contemporary residential building.
Larger form ties-induced cracks or holes cannot be filled, and there is a chance that careless or coarse backfill will cause damage.
However, damp proofing can provide adequate and long-lasting protection for many crawl spaces and basements if proper surface drainage, correctly installed foundation drains at the footing, and the absence of hydrostatic pressure to drive water infiltration are all present.
Why is it important to know the difference?
Water infiltration is continuously impeded by the waterproofing of a concrete foundation. This barrier is made and can withstand hydrostatic pressures by covering the surface with tar or an elastomeric rubber coating.
These substances can be manually applied or sprayed over the surface. How frequently the structure will have to cope with standing water is the major factor to consider when determining whether waterproofing is required.
This decision will take into account the foundation wall’s depth, how the interior space is used, and the climate in the area. However, in most cases, waterproofing is required when there is any doubt about the matter.
Similar to waterproofing, damp proofing involves applying a coating to a concrete surface. This coating substance creates a membrane and is typically based on asphalt.
The main distinction between waterproofing and damp proofing is that when hydrostatic pressure is present, this membrane isn’t anticipated to stop standing water from penetrating.
In other words, damp proofing won’t totally seal the surface the way waterproofing will, but it will prevent minor amounts of moisture from ruining the surface. Additionally, concrete that has significant fractures or holes cannot be repaired by damp proofing.
However, damp proofing is rarely used in contemporary home construction, even when appropriate surface drainage is possible and drains are placed correctly.
What are some common techniques for damp proofing?
The most popular techniques used to make a building moisture proof are
This method of damp proofing involves adding a water-repellent membrane or damp proof course (D.P.C.) between the source of the moisture and the area of the structure next to it.
Flexible materials including bitumen, mastic asphalt, bituminous felts, plastic or polythene sheets, metal sheets, and cement concrete may be used in damp proofing courses.
A course for damp proofing can be installed horizontally or vertically in walls, floors, etc. Tanking is the common name for the provision of a damp-proofing course in a basement.
When providing damp proof course, the following general guidelines must be followed:
The damp proofing course, excluding the rendering, should extend the full thickness of the walls.
To prevent damage to the damp proof course, the mortar bed that supports it needs to be level, even, and devoid of projections.
A constant projection should be given while laying a damp-proof course.
The horizontal damp proof course should be installed continuously at wall intersections and corners.
A cement concrete fillet with a 7.5 cm radius should be provided at the junction when a horizontal damp proof course (such as a floor) is carried to a vertical face.
In order to guarantee a comprehensive and continuous barrier against the passage of water from floors, walls, or roofs, each damp proof course should be put in the proper relationship to other damp proof courses.
The damp proof course shouldn’t be left visible on the wall surface because doing so could cause damage when the wall is finished.
Complete Damp Proofing
The concrete mix is given specific water proofing compounds as part of the integral damp proofing procedure in order to make it impermeable. The following three forms are possible for the typical water-proofing chemicals.
Chalk, talc, and fuller’s earth-based compounds may, according to the mechanical action principle, fill the gaps in concrete.
Alkaline silicates, aluminum sulfate, calcium chlorides, and other substances that chemically react with concrete to form water-resistant concrete.
The water repulsion principle is used by substances like soap, petroleum, oils, and fatty acid compounds like calcium, sodium, and ammonia stearates, among others. Concrete becomes water-repellent when they are combined with it.
Commercially accessible substances like Silka, Permo, and Publo, among others.
The manufacturer’s instructions will determine how much water proofing compound to apply to cement. To make mortar or concrete waterproof, one kilogram of water proofing compound is typically used with one bag of cement.
Through the pores of the substance used for finishing, moisture might enter. The pores must be filled in order to prevent moisture from entering them. The surface treatment technique involves coating the surfaces that moisture enters with a layer of chemicals or compounds that are water resistant.
Rainwater penetration can be greatly reduced by using water-repellent metallic soaps like calcium and aluminum oleates and stearates. The exposed surfaces must be carefully pointed and plastered using water proofing materials such as sodium or potassium silicates, aluminum or zinc sulphates, barium hydroxide, and magnesium sulphates, among others.
Only moisture that is superficial and not under pressure can be treated on the surface. Sometimes water repellent solutions may be sprayed on the exposed stone or brick wall face. It has been discovered that walls that are plastered with cement, lime, and sand mixed in a ratio of 1:1:6 efficiently reduce wall moisture caused by rain.
Cavity wall building
Construction of cavity walls prevents damp effectively. In this technique, an outer skin wall protects a building’s main wall, leaving a space between them. The cavity stops moisture from permeating the inner wall from the exterior.
In this method of damp proofing, a coating of rich cement mortar that is resistant to water is applied under pressure over exposed surfaces to provide water resistance or over pipelines, cisterns, etc. to provide water resistance. A device known as a cement cannon is used to do the process.
The cement cannon comprises of a machine with components for mixing materials and a compressor for pushing the mixture via a flexible hose pipe with a diameter of 50 mm while it is under pressure. The hose pipe features a nozzle at the unconnected end to which water is forced through another connection.
Prior to treating a surface, it must first be completely cleaned of all debris, including dirt, dust, grease, and loose particles.
Cement mortar consists of 1: 3 cement sand mix, is shot on the cleaned surface with the help of a cement gun, under a pressure of 2 to 3 kg/cm2. The nozzle of the machine is kept at a distance about 75 to 90 cm from the surface to be gunited.
The mortar mix of desired consistency and thickness can be deposited to get an impervious layer. The layer should be properly cured at least for 10 days. Since the material is applied under pressure,it ensures dense compaction and better adhesion of the rich cement mortar and hence the treated surface becomes water proof.
This entails applying pressure to cement grout to push it into fissures, cracks, and other openings in the ground or in structural elements of buildings.
As a result, the foundational elements and structural parts that are susceptible to moisture intrusion are strengthened and made water-penetration-resistant.
This technique works well to prevent elevated ground water from seeping through a building’s foundation and substructure.
What are some common techniques for waterproofing?
Building waterproofing is crucial because it creates an impenetrable barrier over foundations, roofs, and walls to protect them from water. The materials used most frequently for waterproofing in building construction are listed below.
The supplies are readily available from masonry product vendors, making this procedure the simplest. Additionally, they are simple to combine and utilize in interior wet spaces like bathrooms.
However, because it is not exposed to weathering and sunshine, this approach does not go through the process of contracting and expanding.
A waterproof deck covering, such as those found in bridges, dams, sewage and water treatment plants, and tunnels, can be made using the cementitious method of waterproofing.
Waterproofing liquid membrane
This kind of coating uses a primer coat and a few top coats that are troweled, sprayed, or applied with a roller. This offers more flexibility compared to waterproofing using cementitious materials. This is due to the fact that as the liquid dries, your wall acquires a rubbery layer.
In actuality, the elongation properties of such a method can increase by up to 280 percent. The manufacturer’s choice of polymer for the liquid waterproofing application will determine this, though.
Waterproofing using Bituminous Coating
Bituminous coating is a different method for waterproofing a building’s construction. Flexibility and water resistance are provided by its reinforced fiber characteristics and polymer grade. This technique, which is good for concrete foundations, is also known as asphalt coating.
But when exposed to sunlight, the bitumen-based elements in this kind of coating solution might not be the best. This is because with time it weakens and brittleness develops. More malleable materials, such as acrylic or polyurethane-based polymers, can be used to modify it.
Waterproofing using Bituminous Membranes
You can choose this procedure if you choose a waterproof deck coating because of how well it has been used for low-sloped roofs in the past. Due to the mixture of asphalt, filler, and polymers, it is self-adhesive. To increase adhesion, certain oils and resins have also been used.
On the membrane, there are both covered and exposed torch kinds. Due to the mineral granular aggregate, the exposed type can withstand the ravages of weathering.
Waterproofing with Polyurethane Liquid Membrane
The somewhat more expensive polyurethane liquid membrane is another type of waterproofing. Basically, it is employed in regions with flat roofs and those that are subject to the elements.
However, despite its flexibility, this sort of waterproofing is not very resistant to moisture.
Therefore, when using this procedure, be sure to check the concrete slab for moisture content. If not, you will eventually see that the membranes start to de-bond or peel.
In conclusion, you can inspect any area of the building’s exterior that needs waterproofing, including the bathrooms and kitchen, basement, balconies, decks, green roofs, swimming pools, walls, and water tanks, among others.
As a result, you can decide which kind of waterproofing technique can be used in a specific situation. To make sure what you are doing is correct, you can also consult experts.
When should you use Waterproofing or Damp Proofing?
The structural stability of the structure is seriously threatened by poor waterproofing.
Construction projects may sustain structural damage as a result of inadequate or poor waterproofing of the concrete and roof.
Joints exposed to water or foundation cracks might cause more severe structural issues. Leaks, spalling, and degradation are a few of these.
Another frequent and challenging waterproofing issue is mold growth. If the structure is made of wood or has wooden furnishings, moisture from water infiltration will cause the wood to rot or delaminate.
Mold spores are also dangerous to your health. This can cause allergies, asthma, rashes, and fungal infections in people who are exposed to it. A WHO research on the subject claims that water leaks in buildings constitute a health risk and that damp spots on the wall are responsible for the spread of about 50 dreadful diseases.
The use of high-quality materials by qualified craftsmen has proven to be an efficient way to solve and avoid minor moisture, seepage, and leakage issues.