where is my damp proof course

A damp proof course (DPC) is an essential part of a property that protects your home from moisture rising up from the ground (aka, rising damp). You can find it by checking the outside of your house and locating a seal that runs horizontally across the brickwork. It usually sits about 6 inches up from ground level.

Full Answer

What is the purpose of damp proof course?

What is a 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 to mould form­ing inside …

Why is a damp proofing course so important?

Sep 03, 2019 · Check for about 100-150mm above ground level for slate in the pointing. See if theres any holes been drilled for a liquid DPC. Just because theres mould and peeling paint doesnt mean its rising damp. Could be penetrating down from windows and sills. Check for gaps and cracks around windows and sills.

What is damp proof course DPC and its properties?

Dec 10, 2016 · The damp proof course (DPC) is generally applied at basement levels, which restricts the movement of moisture through walls and floors. The selection of materials for the damp proof course and its various methods of applications in buildings is discussed. Materials for Damp Proof Course (DPC) Properties of Materials for DPC

How to drill and inject a damp proof course (DPC)?

Where should my damp course be? Damp proof courses in walls should: Be at least 1.5cm above ground level if the wall is external. Join up with any damp proof course or membrane in the floor. Be at least 2.25cm above the bottom of a cavity wall cavity unless a cavity tray is installed. How do you cure damp? How to get rid of damp Buy a dehumidifier.

GarethSE5

I have a ground floor flat in a Victorian (i think) terrace. There's damp in the exterior walls (mould, peeling paint), but not the interior walls. I've done a bit of research and think that the gravel in the back garden and the paving in the front might be 'bridging' the existing damp proof course because they raise the ground level above it.

handyman77

Maybe in manchester they dont have damp courses in london they generally do!

ei8htbuildingservices

Sorry tony! Handyman is right,every house i have worked in has some form of damp course, otherwise they would all be damp.

maltaron

Many Victorian and pre WW2 houses had blue brick or hard red engineering bricks for a damp course. Look for 2 courses of blues or reds that look denser than commons. If so, check that they are not bridged by soil anywhere, air bricks should be below or in the DPC.

GarethSE5

Many Victorian and pre WW2 houses had blue brick or hard red engineering bricks for a damp course. Look for 2 courses of blues or reds that look denser than commons. If so, check that they are not bridged by soil anywhere, air bricks should be below or in the DPC.

tony1851

Manchester builders did build-in some kind of DPC's into some housing stock going back into the mid 19th C. .

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What is the choice of material to function as an effective damp proof course?

The choice of material to function as an effective damp proof course requires a judicious selection. It depends upon the climate and atmospheric conditions, nature of the structure, and the situation where DPC is to be provided.

What are the properties of damp proofing material?

Properties of Materials for DPC. An effective damp proofing material should have the following properties; It should be impervious. It should be strong and durable and should be capable of withstanding both dead as well as live loads without damage. It should be dimensionally stable.

What should a DPC cover?

The DPC should cover the full thickness of the walls, excluding rendering. The mortar bed upon which the DPC is to be laid should be made level, even and free from projections. Uneven base is likely to cause damage to DPC.

What is DPC material?

DPC Material for floors, roofs etc. For greater wall thickness or where DPC is to be laid over large areas such as floors, roofs, etc., the choice is limited to flexible materials that provide a lesser number of joints like mastic, asphalt, bitumen felts, plastic sheets, etc.

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.

What is DPC injection?

DPC injection. 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.

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. ...

What is an electro osmotic damp proof course?

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.

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.

When Is Damp Proofing Necessary?

The International Residential Code (IRC) states that waterproofing is required “in areas where a high water table or other severe soil-water conditions are known to exist.” Section R406 of the IRC states that in areas where waterproofing is not required, below-grade foundation walls should be damp-proofed.

How Does Damp Proofing Work?

Damp proofing is typically achieved through a coating that is either sprayed on or rolled onto the outside of the wall. A damp proof course is a barrier that prevents rising damp, which is when water from the soil seeps up into the foundation. Damp proofing can also be integral when added to the concrete mix, the concrete itself water resistant.

What Are the Best Damp Proofing Methods?

Poly Wall Blue Barrier Liquid Wrap 2300 is a silane-polymer resin that can be used in the process. It applies right over the substrate surface and penetrations (after they are prepped with joint filler). Sidings can be applied to Blue Barrier Air Barrier products the day after installation.

Damp Proofing Tips

Historically, an inexpensive and common method was to spray tar on foundation walls and footing joints. This is no longer recommended because the tar contains harmful VOCs and the material can become brittle and flake away over time.

Take the Next Step Toward Effective Moisture Protection

Damp proofing is typically done during original construction to reduce moisture transfer from soil through a foundation wall. Whether you choose roll-on, spray-on, sheeting, flashing, rods, or a combination of products, the best damp proofing materials are safe and effective.

Why is it important to have a damp proof course?

The damp proof course prevents damp from the ground rising up the walls and damaging your property. Properties which have no appropriate damp protection layer or has a damaged damp course may be affected by excess ...

When was damp proof course required?

A damp-proof course is a standard element which is required when building a property. Damp-Proof Coursing was made compulsory in 1875, however many DPC’s installed in the immediate period after this were laid shoddily and no longer fulfil their purpose. Initially DPCs consisted of slate or lead barriers, fitted into the walls to protect ...

Why does my DPC fail?

A DPC may fail because it was not fitted properly or may fail due to deterioration, localised damage or bridging. If the DPC fails then your property may be suffering from rising damp. Rising damp is moisture which defies gravity and moves upwards through walls as a result of capillary action.

What happens when you have no damp protection?

Properties which have no appropriate damp protection layer or has a damaged damp course may be affected by excess moisture rising from the ground. This excess moisture can affect plaster, decoration and can even result in wet rot, or dry rot affecting unprotected timbers.

How to tell if a wall is damp?

If you suspect that your wall is affected by damp then you should inspect the outside and inside off your property looking for defects that could cause damp to affect your wall. You could then use a moisture meter which will tell you if the wall has a higher moisture content than it normally should be.

Does misdiagnosis solve damp?

It is crucial that a specialist accurately identifies the source of your damp problem. As misdiagnosis will give the wrong remedial repair work which will not solve the damp problem and will cost you more as the work will need to be done twice.

Does moisture damage fabric?

Excess moisture gaining access to your property can result in a range of different damp issues causing damage to the fabric. It is therefore vital that you ensure that your property has an effective damp proof course in place to repel water from the ground. Tired of reading? Listen to this article!

What is damp proof course?

It is a barrier or obstruction that is primarily designed to prevent the moisture rising by the capillary action. The capillary action through which the moisture rises is known as the rising damp.

What is damp proofing?

In other words, a damp proof course can be defined as the layer of material that is used to prevent the penetration or passage of moisture inside the structure through the floors, walls or roofs. It is commonly applied at the basement level of the structure and thus prevents the passage of moisture through the floors and the walls. 1.1.

What is surface treatment?

Surface treatment includes the method of laying a water repellant layer or water-resistant substance on the surface through which dampness is likely to occur . It is the most common method of damp proofing when the moisture or dampness occurs superficially.

What are the factors to be considered during the construction of a DPC?

Some of the factors that must be considered during the construction of the damp proof course are as follows: a. Before the damp proof course is laid, the mortar upon which it is to be laid must be made level, even and free from any sorts of projections.

What ratio of cement should I use for DPC?

a. For DPC above ground level, it is desirable to use cement concrete of ratio 1:2: 4 (M15). In the case of a damp and humid atmosphere, a richer mix of concrete must be used. Various water-resistant materials such as Pudlo, Impermo, Waterlock may be added to the concrete mix to make it denser.

What are the desirable properties of damp proofing?

The desirable properties of the materials used for the damp proof course can be listed as follows: a. The material used for the damp proof course must be impervious i.e. it must prevent the passage of moisture through it . b. The material must be strong as well as durable.

How deep does mastic asphalt spread?

When the mixture is hot, the consistency is such that it allows the mixture to spread evenly to a depth of about 2.5cm to 5cm. Upon cooling, the mixture sets. However, special care must be taken while laying the mastic asphalt as the damp proof course. b.

How to find damp proof course?

You can find it by checking the outside of your house and locating a seal that runs horizontally across the brickwork. It usually sits about 6 inches up from ground level.

What is damp proofing?

Once this is determined, there are three types of damp proof course available on the market: 1 Cream or liquid wall injections: The application requires holes to be drilled into your walls. 2 Mortar injections: The same as above, except, mortar is caulked into the holes. Used in homes with more internal wall rubble and those prone to voids. 3 Electroosmotic course: A non-chemical alternative using copper or titanium wiring to create a small electric charge that stops the water from rising. It uses a scientific method to reverse the polarity of the capillarity, keeping the rising water below the level of the new damp course.

How many types of damp proofing are there?

Type of damp proofing: As previously mentioned, there are three types of damp proofing treatments available. Your damp proofing cost will depend on which treatment you need.

How far up from ground level should a damp seal be?

It usually sits about 6 inches up from ground level. This seal might not exist on homes built before 1875 – before a DPC became a compulsory building regulation. If that’s the case, you will need to invest in a damp course to avoid issues such as: Reduced wall integrity. Aggressive mould stains.

Can you damp proof exterior walls?

If you’re damp proofing exterior walls, you can expect to spend a bit more as there are more processes to consider. For example, if the rising damp was caused because the exterior ground level rose above the DPC in the wall, you will also need to lower the ground level.