A damp-proof course is an essential protective measure if you’re attempting to prevent moisture from seeping into your house. A damp-proof course creates an impermeable waterproof barrier to keep water from rising into a home, and it can shield your property from costly and dangerous problems caused by dampness.
A damp-proof course is a waterproof membrane that runs the length of a structure and is laid beneath the paving. It prevents moisture from getting into your home via gaps between blocks, which can cause rot and ruin in addition to dampness problems later on.
However, since older homes may not have ever had one installed, it’s possible that yours does not as well. Before they become serious, a wet-Proof specialist can help you find and repair any problems.
To help you appreciate the significance of damp proofing your property, the Danford, Brewer & Ives professionals have created their definitive guide to damp-proof courses.
What Is a Damp-Proof Course?
A damp-proof course is a type of waterproofing that protects the property against moisture, dampness, and overflow. A wet-proof course works as an effective waterproof barrier by keeping moisture out of the masonry and preventing it from rising through the brickwork and into the home.
A damp-proof course is typically built just above ground level and is primarily intended to keep rising damp at bay. There are several different types of damp-proof courses, including ones that use a damp-proof cream to fill the ground floor masonry.
Without a damp-proof course to establish a waterproof barrier, excess groundwater and moisture can seep into the bricks and cause property damage. If left untreated, this damp problem might result in structural as well as health and safety difficulties for your house.
How Do Damp Proof-Courses Work?
There are a variety of different types of damp-proof courses, and they all function in somewhat various ways.
A minimum of 150mm of waterproofing is required above ground level for any damp-proof course. This is a legal requirement that ensures that the waterproof barrier is established at ground level rather than below it. Because a damp-proof course is designed to shield against rising damp, which comes into a property from the Earth’s surface, they are frequently placed in masonry or brickwork on the lowest floor of a house.
Chemical injections are used in modern damp-proof courses, but they are most effective when combined with other damp-proofing techniques, such as a damp-proof membrane. The following are the most common types of damp-proof courses that may be put on your property:
Chemical Damp-Proof Course
A chemical damp-proof course is injected directly into the masonry and brickwork of a property, and it’s most effective when applied at 150mm above ground level. It’s made up of a special damp-proofing cream that, once it’s been allowed to dry, produces an efficient waterproof barrier in the brickwork.
Mortar Damp-Proof Course
A wet-proof course is also pushed into any drilled holes in a wall, and it must be injected 150mm above ground level to function effectively. The mortar, once injected, produces a waterproof barrier by filling in these gaps and eliminating any chances of rising damp moving through the walls via any cracks in the brickwork.
Non-Chemical Damp-Proof Course
Non-chemical damp-proof courses are also available, with the most popular being an Electro Osmotic damp-proof course. This differs from a chemical damp-proof course in that it employs metal wiring to generate an electric current. Rather than forming a physical, waterproof barrier, this electric charge causes the wall’s polarity to change. This means that rising damp is pushed away from the brickwork rather than drawn up through it.
This method isn’t as popular since it is more time-consuming and complicated to set up in comparison to a chemical injection.
Damp-Proof Membrane
A damp-proof course, when combined with other damp-proofing methods, provides a good barrier against rising dampness. The most popular form of damp-proofing is a wet-suit membrane, which creates an actual physical impermeable barrier to prevent moisture and dampness from penetrating.
A damp-proof membrane is a thick sheet of waterproof material that’s put above or below the floor. A damp-proof membrane must be at least 1,200-gauge thick and installed with sheets overlapping, forming a continuous barrier.
Why Do I Need a Damp-Proof Course in My Home?
The basic objective of a damp-proofing course is to prevent various sorts of damp and water damage that might result in expensive and even deadly repairs. Excess moisture and water are causes of dampness, and the damp-proof course works to establish a waterproof barrier against it.
The most common reasons for dampness in your home are:
The structural integrity of the building is at risk. Damaged timbers, decaying plaster, and damaged decorations are all examples of aesthetic damage. Mould is another problem that needs to be addressed. Wet and dry rot are other issues you’ll want to be aware of. Respiratory illness can result from prolonged exposure to dampness or mouldy air conditioning vents.
There are various sorts of dampness that may be found in a house, including condensation, rising dampness, and penetrative dampness. The primary goal of a damp-proof course is to keep out rising dampness, which happens when the water rises through the brickwork via capillary action and travels vertically through bricks and mortar.
If you let rising dampness, go unchecked, it can wreak havoc on your home’s foundations. Fungus and mould are additional adverse effects, which may cause respiratory issues and increase the risk of health problems for people who live on the property.
A lack of a damp-proof course is one source of rising dampness, but it can also be caused by significant leaks, floods, or other damaged infrastructures such as drains or pipes. As a result, it’s critical to make sure your home is properly waterproofed with an effective damp-proof course in place to keep moisture and water out.
How Do I Know If My Home Has a Damp-Proof Course?
Your home should already have a moisture-resistant course in place, although some variations are permitted. Since the late 1800s, it’s been a legal requirement for a property to have a damp-proof course built. This means that contemporary homes will already have one in position, and it’s quite likely that older residences would as well.
However, there’s a small chance that a Victorian-era home may never have been retrofitted with a modern damp-proof course. If this is the case, any additional damp-proofing measures must be updated as quickly as possible.
A damp-proof course may deteriorate over time, resulting in your property being affected by damp problems. The ground might shift, walls may sink, or brickwork and masonry might collapse after the damp-proof course is put in place. Regular inspections and a professional damp and timber survey can help you spot any concerns with the damp-proof course in your home or if you’re looking to buy a property.
If you suspect that your damp-proofing course is failing, there are a few obvious warning signs. The following are all major indicators that your house has a wet problem, which may be the consequence of a faulty damp-proofing system:
Smells damp, musty, or mushroom-like the following are examples of mould and fungal growths: Damp patches on the walls Mould and fungus infestations Damage to masonry or brickwork Crumbling or broken masonry or brickwork Tide marks on the walls unusual growths on the outer walls
Signs of dampness can be found on both internal and external walls, but the most telling sign of moisture is most likely a powerful musty odour that permeates throughout the house. If you notice salty tidemarks on the walls, this is an indication of rising dampness, which we’ve previously said generally occurs as a result of a failed damp-proof course.
Of course, one damp-proofing course isn’t the only cause of dampness, and various types of damp can produce a variety of issues and demands different solutions. If you’re concerned about any problems relating to moisture, it’s critical to get an expert evaluation so you know what’s causing it and how to fix it.
Any damp must be removed before the damp-proof course is installed. The new damp-proof course may then be injected or set in place after the old one has been eliminated. To get access to the walls, bricks or timbers may need to be removed, or it might as be simple as drilling holes and injecting a chemical damp-proof course.
How Much Does a Damp-Proof Course Cost?
The cost of a damp-proof course varies from one property to the next, taking into account a variety of variables. The following are the most important factors that influence the overall price:
The Size of the Home
In general, the more spacious a property is, the more it will cost to have a damp-proof course put in. This translates into greater costs for additional supplies and materials, as well as increased labour time needed to complete the damp-proof course.
The Type of Damp-Proof Course
There are various types of damp-proof courses available, each with its own set of expenses. Simple chemical injection is the most cost-effective damp-proof course available, but a physical wet-barrier membrane may cost more per square meter to install.
The Amount of Work Needed
The cost of constructing a damp-proof course is also influenced by the amount of time and effort required to properly install it. Installation may be more difficult in older homes, making it more expensive. If masonry or brickwork must be destroyed or access to ground level is restricted, costs will rise as well
Damage Already Caused by Damp
If your property has already been damaged by dampness, you’ll need to have the damage repaired before having a new damp-proof course put in. You must also include any structural repair expenses, as well as any redecorating costs that may occur later. Keep in mind that the earlier you detect issues linked to dampness, the sooner they can be addressed. If damp is allowed to grow and spread unchecked, the cost of removing it and repairing any harm caused will always rise over time.
For a precise quote, contact DBI Ltd. There are many variables to consider before a professional can provide an estimate for the cost of a damp-proofing project.
