how to damp proof course a house

Does your property have a damp proof course?

These in-built damp proof courses are usually very effective, however, the widespread use of DPC’s only came about in the 1920s. As a great number of houses in the UK are older than this, so it is possible that your property does not have a damp proof course.

What is the best way to damp proof your home?

Damp proofing rods are very easy to install and will keep your home protected for years. When using a chemical DPC isn’t an option, this method is often used. An Electro Osmotic damp proof course uses wiring to create a small electric charge in the walls of your home. This electric charge reverses the capillary action in bricks and mortar.

Do older buildings need damp proofing?

Some older buildings do not have damp proof courses installed during building. Older buildings (built before the 1940s) used lime mortar to prevent moisture from entering the home. These older buildings also had nice, thick walls to stop moisture being an issue.

What is damp proofing?

So, “ damp-proofing ” or “damp proof courses (DPC) ” is a prevention method applied in buildings walls and floors to the entry of moisture in the building, it should be a perfect design. Related article: What is Shoring? Types and Uses

Why do damp proof courses rise?

The damp proof course is designed to prevent water from entering your foundations . However, when the damp proof course is no longer working effectively, or has been bridged, which occurs when structures provide a ‘bridge’ that the moisture can get over or around, this can lead to rising damp in the home. Rising damp is often the easiest to spot since it occurs on the lower level of the property just above the skirting boards. However, it is often one of the trickiest to fix, and it’s worth having a damp proofing specialist come and inspect your damp proof course to determine the cause of the problem.

How to tell if your house is damp?

Most types of damp are also usually easy to identify with a visual inspection of the area since they will show up as moist patches on the wall and can often lead to mould, which shows up as dark stains. Many damp patches will look yellow or brown, and any wallpaper or paint in the area might be cracked or crinkled. While it’s possible to identify damp on your own, it’s worth working with a damp specialist in an older home since they can help to figure out the root cause of the damp, which may not always be obvious. In addition, they can help you determine any other areas of the home that might be at higher risk of damp in the future, allowing you to carry out preventative work before it becomes a problem.

Why do older houses have damp?

Condensation occurs when the warm air that we generate from everyday living activities comes into contact with the cooler surfaces of the walls and ceilings. Here it condensates to moisture, which can create damp patches on the walls. Using a dehumidifier, extractor fans, opening windows or installing a ventilation system is key to avoiding this issue.

Why do gutters get damp?

Penetrating damp occurs when water makes its way from the exterior and into the interior walls of the home. One of the biggest causes for this is problems with the gutters, which can often be seen in older homes. If your older home still has the same gutters that were installed decades ago, chances are that they are no longer effective for the amount of rainfall that we are getting today. Gutters are designed to direct rainwater away, rather than towards your home – but if they’re not working effectively or have sustained damage, the water will be directed towards and often into your home instead.

Is it bad to live in an older house?

Living in an older home can often mean that you are at a higher risk of health problems that are a direct result of damp. Not only can damp issues smell and look bad, but they can also affect your health in a number of ways, particularly when it comes to respiratory complaints. Damp is linked to several respiratory conditions including asthma and will often worsen the condition in people who already have this health problem. People who are exposed to damp in their homes regularly also have a higher risk of developing certain allergies and respiratory infections, and it can have a negative effect on your immune system. This is just one of the reasons why it’s important to spot and treat damp in the early stages and damp proof your older home to prevent further problems in the future.

What is damp proof course?

A damp proof course (DPC) is a layer near the bot­tom of the walls of a house which pre­vents ris­ing damp. In a prop­erty with­out a DPC, water can rise up from the ground through cap­il­lary action and through porous ele­ments in your brick­work. If it creeps through the walls, it can­ing struc­tural prob­lems and poten­tially lead ...

Can DPCs be made out of materials?

More recent houses have plas­tic. DPCs can be made out of a num­ber of mate­ri­als. Although build­ing reg­u­la­tions require the inclu­sion of a damp proof course4 in any new build­ing, they do not spec­ify one sin­gle mate­r­ial.

How to fix damp caused by a failed damp proof course?

Sometimes called a ‘remedial’ damp proof course, this process involves the injection of a ‘damp proof cream’ made from a silicone-based liquid that reacts with the silica in the masonry to produce a water-repelling layer within the wall.

What is damp proof course?

What is a damp proof course? A damp proof course (DPC) is a form of damp proofing installed in a property to prevent rising damp and associated problems. There are various methods to install a DPC so our guide will help you to understand the different types of damp proof course available,why a DPC might fail, and how to fix a broken DPC.

How far from the base of a wall should damp proof be applied?

The damp proof injection is applied at no less than 150mm from the base of the wall and is often a more practical solution than other “solid” damp proof courses.

Why do we need damp proofing?

This form of damp proofing is often used to protect properties from penetrating damp problems when the home has earth retaining walls.

When did damp proofing start?

These in-built damp proof courses are usually very effective, however, the widespread use of DPC’s only came about in the 1920s. As a great number of houses in the UK are older than this, so it is possible that your property does not have a damp proof course. If your property was built after 1920 it is also possible that your current damp proof course has weakened and failed over time to allow water ingress and potential rising damp problems.

Do you need a professional inspection of damp proof?

In circumstances such as this, we would always recommend a professional inspection of the faulty damp proof course to evaluate any necessary repairs.

What is the best material for damp proofing?

Common damp proofing materials: 1 Hot bitumen: Highly flexible hot bitumen is placed on the bedding of concrete or mortars with a minimum thickness of 3 mm. 2 Mastic Asphalt: Mastic Asphalt is obtained by heating Asphalt with sand and mineral fillers up to standard temperature. It is semi-rigid material of good property of impervious and durable. Which is also able to withstand very hot climate heavy pressure.

Why is dampness important in building design?

Dampness not only reduces the strength of the structural components but also gives rise to unhygienic conditions. So, in the building design, damp prevention is one of the important factors to be considered, and every building Should be damp proof. So, “ damp-proofing ” or “damp proof courses ...

What is damp proofing membrane?

In membrane damp proofing, a water repellent membrane is inserted between the source of dampness and the part of the building adjacent to it. Damp proofing material may be like bitumen, mastic asphalt, polythene sheets, bituminous felt, metal sheets, cement concrete, etc. damp proofing course may be provided either horizontally or vertically in floors and walls.

What is the most important factor to make a building long life?

Concept of Damp proofing: The most important factor to make the building long life is to maintain it to be dry or free from moisture traveling through walls roofs, or floors. Dampness is the presence of hygroscopic or gravitational moisture.

How does moisture enter a building?

If the foundation soil on which substructure is is embedded is previous, moisture slowly and constantly travels through the structures founded on the soil. There is also a lot of moisture present in the impervious soils. By the capillary action, this moisture may rise into the floor through the wall. This process of rising groundwater I will also so slowly result in moisture entry into the building.

How does a cavity wall protect against water?

The cavity wall prevents the protection of water inside the building by shielding the main wall by an outer skin wall living a cavity between the two. It is an effective damp proofing technique.

Why does water accumulate on balconies?

Sometimes water may accumulate on balconies and chhajja because of the not proper outward slope, enter the walls through their junction. This type of moisture travel can deteriorate paintings and interior decoration of the wall.

What is damp proof course?

A damp proof course (DPC) is a barrier that stops the water from rising.

What is damp proofing?

A damp proof membrane is a sheet of waterproof material inserted under a concrete floor. Together, the course and membrane seal a property and protect it from ground water.

How do you know if your house is damp?

Isolated damp patches might start appearing on walls. Walls themselves might feel damp to the touch. Plaster or paint might have visible cracks and may start flaking away. We might also see mouldy spots appear, and all of this is often accompanied by a fairly unpleasant musty, damp smell.

What causes damp in a house?

Penetrating damp – essentially when water penetrates through from the outside of a property to the internal walls, this is is usually caused by some sort of building or structural defect, such as a leaking pipe, a cracked guttering, for example.

What is the third type of damp?

However, the third type of damp – rising damp – can be more troublesome and it’s with this type of damp that you really need to know what a damp course is.

What is damp water?

The problem with damp, in a nutshell, is that water rises. The technical term for this is capillary action. It’s also often referred to as wicking. Basically liquid (usually water) will naturally flow in narrow spaces (such as a wall). This means that, over time, an amount of ground water will naturally rise up through the wall or the floor of a building. Indeed, most floors or walls will allow some water to do so.

Is slate a damp proof material?

However, this has not always been the case and although plastic is the damp proof course material of choice these days, it always used to be slate. Slate is a highly resilient material, more than up for the job of acting as a damp proof barrier . However, if the slate cracks or slips slightly out of position, the damp proof course ceases to be effective and will need replacing.

What is a Damp Proof Course?

All modern buildings have what is known as a Damp Proof Course. It is usually abbreviated to 'DPC', and in most buildings less than 30 years old, it consists of a DPM, which is a Damp Proof Membrane, an impermeable layer of material, most often a polyethylene or bitumen-polymer, that is laid in the bedding joint between two courses of bricks.

When did damp proofing become mandatory?

Ground-level damp proof courses have been mandatory in all British buildings since the Public Health Act of 1875 . A typical polymer damp proof course. There are a number of alternatives to the modern dpc-on-a-roll, and these are sometimes found on older properties, particularly those built prior to the Second World War.

How far below the DPC should paving be?

Paving is kept at least 150mm below the dpc and slopes away from the wall at around 1:60. This may need to be increased to 1:40 for some 'difficult to drain' pavings, such as riven flags, or may be decreased for well-draining pavings, such as blocks or plain concrete.

How much space between a DPC and the ground?

Bending The Rules. The Building Regulations require at least 150mm between the dpc and the ground or any paving. This is what is known as 'Best Practice'. However, there are situations where it is just not possible, or practical, to maintain this regulation.

What happens if you breach the 150mm rule?

It should be noted that breaches of the 150mm rule are the sort of thing that is noticed by Surveyors when valuing a property and it can lead to a reduced valuation or a requirement for remedial work to be undertaken.

How high above ground level is a DPC?

The "ground-level dpc" is actually required to be at least 150mm above the ground level (See Building Regulations for England & Wales - Part C, Section 5.5 ). This is to reduce the incidence of 'splashback' from rain, and to ensure a minimum amount of elevation above standing water that may come about in exceptionally heavy rain or other incidents, such as allowing the hosepipe to run unchecked.

How to identify a DPC?

On some properties, identifying the dpc is quite straightforward: it protrudes slightly from the bed joint and could be spotted by the proverbial blind man on a galloping horse. However, on other properties it can be less obvious and may take some poking about and investigating to pinpoint its position.

What happens when a damp proof course fails?

When a damp proof course fails, it allows moisture to enter bricks and mortar. The materials in your home act like straws pulling moisture up from the ground. A DPC is installed to prevent this from happening. When a damp proof course fails, moisture can find a way in. When a DPC fails, and moisture begins to enter the brickwork of a building, ...

How long does a damp proof course last?

A damp proof course, even a properly-installed one, may only last for about 20-25 years. An incorrectly installed DPC likely won’t last this long. Also, if your home has a DPC that wasn’t installed correctly, it may have been letting moisture into the brickwork of your home for some time.

How to fix a DPC?

Damp proof course injection is one of the most DIY friendly form of fixing a DPC. This involves a chemical in liquid or cream form. This is injected into the fabric of your home at the level of the old DPC. It creates a water-repelling layer that will stop damp from rising. Chemical DPC is widely available. All you need is a drill capable of drilling holes in the bricks, and to follow the instructions!

What does rising damp mean?

If you have rising damp, it is likely your damp proof course has failed, or wasn’t installed at all. Either way, you need to fix your DPC.

What is it called when a DPC fails?

When a DPC fails, and moisture begins to enter the brickwork of a building, this is called rising damp. A home with rising damp will have a DPC that has failed. Or it may never have had a DPC installed in the first place. A damp proof course, even a properly-installed one, may only last for about 20-25 years. ...

How to tell if your house is damp?

But how can you tell why this damp is happening? Well, the damp gives us clues. If you have a damp ‘tide mark’ on the exterior or internal walls of your home, this is a sign of rising damp spreading up your walls. Penetrating damp leaves isolated patches of damp on the walls of your home. Rising damp, on the other hand, rises up through the brickwork. So, if your damp is at a consistent level on the walls of your home, you have rising damp.

What does it mean when you have a damp spot on your house?

Well, the damp gives us clues. If you have a damp ‘tide mark’ on the exterior or internal walls of your home, this is a sign of rising damp spreading up your walls. Penetrating damp leaves isolated patches of damp on the walls of your home. Rising damp, on the other hand, rises up through the brickwork.