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Damp Proofing

Is efflorescence a sign of damp? Should you be worried?

January 9, 2023 by Carl Lewis

Efflorescence can appear on both external and internal walls of a property. It is a white substance that consists of salt deposits which form on the walls surface.

This salt is present in building materials such as masonry and mortar. It is also present as natural salts, in the ground below a property.

Efflorescence is a sign of damp in the walls of your property. Water moves through the building materials via capillary action. As this happens, it collects salts. Once this liquid reaches the surface it evaporates and only the salt remains. This is what causes the white deposits.

This is unsightly, it is also a clear sign that excess moisture is present in the brickwork. At this point, your main goal should be to identify the problem that is causing damp and fix it.

is efflorescence a sign of damp

On external walls the salts can be cleaned, but if the underlying issue remains, the efflorescence will return.

On internal walls the damage to internal plaster and decorations can be more severe. This means, you will definitely need to solve the problem before you replace any internal surfaces or redecorate. If the issue remains after you redecorate, all of your hard work will probably go to waste.

If there is still moisture passing through to the surface, it will simply result in the same problem repeating itself.

Does efflorescence damage brickwork

On its own, efflorescence doesn’t damage brickwork, but it is unsightly and can indicate a deeper problem. It can also cause damage to things like external masonry paints. The salt can cause paint to bubble and flake.

When efflorescence is clearly visible on brickwork, this means there is excess moisture in the masonry. This can cause separate problems that can be more severe.

One such problem is spalling bricks. This is another condition caused by excess moisture and is far more destructive than efflorescence. Spalling causes the bricks to crack and deteriorate. This is often noticed with the fronts of bricks falling off and the brick materials becoming softer and crumbling.

Spalling happens due to excessive water being present in the brickwork. This expands during freeze thaw cycles. Because the masonry lacks flexibility, it results in damage to the bricks.

During the manufacturing process, standard house bricks are kiln fired. This hardens them, as well as making them denser and less porous. As a general rule, the face of the brick is less porous than the inside of the brick. Therefore when spalling damages brickwork, it can actually make damp even worse, as it will allow more water to penetrate the surface.

Another problem this causes, is blown pointing. Just like the bricks, the mortar will expand and contract, causing it to dislodge between the brickwork. This will provide another route for additional damp to enter.

Efflorescence can be scrubbed off brickwork. This can be helped with an acid-based brick cleaner. However, you should do your best to identify the cause of damp and remove it, or the problem could return, and you could have more serious issues.

If in doubt, you can hire a local damp company to identify the underlying issue. Most of these companies offer some kind of free survey.

To see local damp companies that offer this kind of service Click Here

Treating efflorescence on interior walls

If you have efflorescence on interior walls, this can cause more aesthetic issues. It will form the same type of white deposits as it does externally. However, it can have a much more damaging effect to internal decorations.

When treating internal efflorescence, it is crucial that you identify and remove the source of extra moisture. If your property is relatively new, this could be natural moisture left in the brickwork, following construction.

In this case, you can scrub away the efflorescence with a stiff brush and then treat the surface with a specialist salt neutraliser, designed specifically for this job.

You should leave the surface exposed and apply heat and use something like a dehumidifier to try and extract any remaining moisture. Following this, you can redecorate.

However, in most cases there will be an underlying issue, such as rising damp, or some form of penetrating damp. It is even possible that internal moisture and condensation is causing problems.

If you have noticeable tide marks at skirting board level, then rising damp becomes more likely, although this could still be penetrating damp.

To learn more about identifying penetrating damp click here

To learn more about identifying rising damp click here

If you do manage to identify an underlying damp problem, there are often DIY solutions that can be carried out by yourself, many of which can be found on this site.

However, if you struggle to locate the cause of damp, it is much better to seek the help of a professional.

If you simply redecorate without repairing damp problems, the efflorescence will return, causing more work and expense to carry out repairs.

Hiring professionals to help with efflorescence and damp

If you do need help to identify the cause of efflorescence, hiring a local damp company is your best solution. Many will offer some kind of free survey, whilst others may charge a small call out fee.

Either way, they will identify the issue for you and recommend treatment to fix it. At this point, you can decide if you hire them to do the work, or if it’s possible to do it yourself.

The best way to hire someone locally, is via a damp comparison website. When you use this type of service, you are talking to professionals who have been vetted by the comparison site. They will also have a profile with customer reviews. This all helps you to find a reliable company.

The other major advantage is the savings you can make on work. Multiple damp companies will see your job, and this results in very competitive quotes. It also makes the chance of free damp surveys much more likely.

You can see a popular comparison site that specialises in damp companies by clicking here

Conclusion

Efflorescence is usually a sign of damp. When you notice the issue, you should take steps to identify the underlying cause as soon as you can. This will help you to lower the chance of more serious issues forming in the future.

In many cases, the fix for efflorescence can be quite simple and there is often a DIY solution. However, if you are struggling to resolve the problem, you should let a professional take a look.

Filed Under: Damp Proofing

What is a damp proof guarantee & how long does it last?

July 1, 2022 by Carl Lewis

Most professional trades will offer some kind of guarantee when they carry out work on your property. The same is true for damp proofing companies. They will usually offer some type of damp proof guarantee, and this will cover the customer for any future issues relating to the work carried out.

For example, if a company installs a new DPC (damp proof course) and a couple of years later rising damp returns, the company will need to come out and rectify the problem.

This is obviously an advantage to doing the work yourself, for 2 reasons:

  1. The original job will be done professionally. Due to this you would expect the work to be of a high standard and it shouldn’t have any issues.

  2. If there are issues, you don’t have to repair it yourself, and you don’t have to pay more money. The guarantee will cover the cost.

As you can see these are major advantages and it can remove the stress of repeat dampness. Most damp proofing companies will offer guarantees that last decades. This shows they are confident in the original work not having any issues.

what is a damp guarantee

How long does a damp proof guarantee last?

The duration of a damp proof guarantee can vary, but it will usually range between 10 – 30 years. This will depend on who you hire. However, the industry standard is 20 years, and, in our experience, this is offered by the majority of established, trusted damp proofing companies.

If you are quoted for work and there is only a 10-year guarantee, it might be worth shopping around a little. Also, if a company is offering a 30-year guarantee, whilst this is great, you should check how established the company is. For example, a one-man local business that’s been trading for a short time may offer 30 years, but is this company guaranteed to be around in 3 decades.

These are just things you need to consider. Obviously, a longer policy will give you more protection, but a guarantee with no company backing it is essentially worthless.

Due to this, if you are carrying out large scale damp proofing work, it is worth shopping around to find the best possible quotes and guarantees, from the best possible companies.

Comparing quotes and damp-proof guarantees

By far the easiest way to compare is using online comparison sites. Doing this will allow you to receive multiple quotes from a variety of companies.

Using these types of sites has several advantages. These include:

  • You can find a large number of accredited damp proofing companies in one place.
  • The comparison site will screen companies who are advertising on their website. This means, they are who they say they are, and you have less chance of hiring cowboys.
  • Previous customers rate and review the companies. As a result, you can read reviews and ensure you are hiring a good company, with good previous feedback.
  • All qualifications and guarantees will be available to view on the company’s profile page.
  • Finally, these sites are competitive marketplaces. Companies know they are competing against each other, so you are far more likely to get competitive quotes. We have seen discounts of 30% or more.

To see our favourite damp proof comparison site, Click Here

What if your damp guarantee company goes bust?

As we have already mentioned previously, a guarantee with no company to back it up is not worth the paper it is printed on, and this can happen. Many companies go out of business every year. Figures suggest that 20% fail in their first year. This jumps to 60% in the first 3 years and only 1 in 3 will last a full decade (10 years).

Considering these statistics, it is no surprise that many damp companies do go out of business and are unable to honour their damp proof guarantees.

So, what can you do?

Really the best thing you can do, is to make sure you hire an established firm. This would be a company that has already been in business for many years (10+ years preferably).

If you do find yourself in the situation, where a company has gone out of business, and can’t honour your damp guarantee. Don’t worry, not all hope is lost.

If they were a reputable company, their guarantee should have been backed by some kind of insurance company, who will honour the guarantee

Failing that, there are companies who can offer new guarantees for existing work. Generally, you will need to pay a small one-time fee of £300 – £400. However, after this, the work will be covered again for somewhere between 20-30 years.

With that said, this is providing there is no current damp issue for the work being guaranteed.

Unfortunately, if you don’t have an insurance backed guarantee and your damp proofing has failed, you will be out of luck and the burden of payment will lay on your shoulders.

Conclusion

As with any guarantee, a damp proof guarantee is a great thing to have. It ensures that your work is protected from future defects that allow damp to re-enter your property.

To ensure you get good cover that will be reliable way into the future make sure you hire established companies who offer insurance backed guarantees for the work they carry out.

Filed Under: Damp Proofing

How much does damp devalue a house?

June 25, 2022 by Carl Lewis

Whether you are selling a house or buying, many things could affect the property’s value. This includes structural issues and cosmetic/decorative issues. Damp can fall into either of these categories depending on its severity. Therefore, damp can definitely affect the value of a property.

How much damp devalues a property, will depend on several factors. These include:

  • The extent of the damp and the damage it has caused.
  • The type of damp (condensation, penetrating damp, or rising damp)
  • How difficult it is to fix.
  • And finally, the cost to fix it.

However, there is good news for sellers.  In the vast majority of cases, dampness is easy to fix and often quite affordable.

how much does damp devalue a house

Condensation is by far the biggest cause of damp and mould in homes. This is caused by a lack of ventilation and air circulation. Solving the issue can be as simple as installing extractor fans in high humidity areas, such as bathrooms and kitchens. Also, things like dehumidifiers, improving insulation and anti-condensation paints can help.

If mould has formed as a result of condensation, this can usually be removed with a simple mould spray and a cloth to wipe down the surface.

The next most common type of damp is penetrating damp. As the name suggests, this is water penetrating from outside the property. If you can identify the cause of penetrating damp, there is a good chance there is a DIY solution or a relatively affordable professional fix.

Finally, the least common, but often the most damaging, is rising damp. However, even rising damp often has DIY solutions, such as injectable DPCs. As well as slurry and epoxy resins that can be applied to floor surfaces such as concrete.

How to stop damp devaluing your house sale

If you are selling a house, then damp can certainly lower its value. This happens because potential buyers will see it as a job that needs fixing after the purchase. This usually means that the value will drop by at least the value of the work.

Another thing to consider is convenience. Many buyers are not looking for a project, most will want to buy their new home and move in. Carrying out work to fix damp problems is likely unappealing to a majority of people.

As a result, you will have a smaller pool of people interested in the property. This can also contribute to a lower market price. It is simply the result of supply and demand.

For general damp issues in a habitable property, the reduction in value will often range between 10-20%.

A property in a poor state of repair. For example, one with extensive structural and cosmetic damage, this number could be far higher. If a property has been neglected for years or even left vacant. Then damp problems can spread and become far more serious. This could include deterioration of structural timbers through rot and even woodworm. There is even the chance of damage to structural masonry, due to spawling and cracked bricks.

In this type of case, a reduction in potential sale price could be significant.

Stop damp affecting your house sale

Damp is very common and as we have already mentioned, there are lots of simple fixes to the majority of issues. This could be installing extractor fans and repairing external defects, such as damaged pointing, bricks, or render. If rising damp is the issue, an injectable DPC can be installed. Most of these can be done as a DIY project, or you can hire a professional.

Once the underlying problem is fixed, you can use a combination of heat, and good ventilation to remove any excess residual moisture present in the surfaces.

What if you don’t know what is causing damp?

If you are unsure what the cause of damp is, then hiring an expert to inspect the property can be a good idea. However, be aware, free surveys from damp companies will often have an ulterior motive. They want to quote you for damp repair work. This means it is very common for them to over quote for more extensive work.

Therefore, it is often better to pay and have an independent surveyor complete a full survey, that includes timber and damp. This will cost you a little bit of money. However, it will identify problems and tell you what needs fixing.

The main thing to remember is even though you will pay out a small amount of money for surveys and repair work. This will usually have a much bigger impact on the asking price.

According to the government house price index, the average house in the UK was worth £277,000 in February 2022. 10-20% discounts due to damp, could mean a significant drop in the money you receive. As a result, rectifying damp issues before a sale is usually recommended.

How to view damp as a buyer

If you are on the other side of the transaction and looking to buy a property, damp is something that can be used as a bargaining tool to potentially reduce the price. This can be particularly true for properties that have been on the market for a while.

Correctly identifying damp, and then resolving the issue with a professional can be expensive. You can factor this into any offer that you make.

You can also factor in the inconvenience and time this may take. For example, if you are not able to live in the property whilst work is being carried out, there are additional expenses to consider. Such as:

  • Mortgage payments for the house whilst you aren’t living there.
  • Rent or other living expenses before moving in.
  • It may hold up other jobs such as decoration that may be needed.

Also, if the property has been on the market for a while, you know you are not competing with a large pool of potential buyers, compared with a home that is ready to move into.

Minor damp issues could allow you to negotiate a good deal on a property. Plus, if you don’t mind getting your hands dirty, it is likely you can fix the majority of problems yourself, as a DIY damp project.

Conclusion

There is no doubt that a property’s value can be affected by damp. However, in reality, the cost and effort to fix most issues are usually quite low, especially for more minor damp issues.

If you are selling a property and want to achieve the best possible price, it is often wise to just bite the bullet and get the repairs done. Simply fixing underlying issues, drying internal surfaces and a little redecoration, can have a significant effect on your potential sale price, so it is usually worth the extra effort.

On the other hand, if you are buying, you can use damp issues to your advantage. Try to figure out the cost implication of work that needs doing. Include all costs and factor this into the offer you make.

Filed Under: Damp Proofing

Can you damp proof breeze blocks?

December 5, 2021 by Carl Lewis

Breeze blocks are a common building material used in the construction industry. In new construction they are often used for the internal leaf of a cavity wall. The outer leaf will then be constructed of more aesthetic masonry. This will usually be facing bricks of some kind or stone.

Also, blocks are considerably cheaper and considering they will be covered internally it makes sense to use them here to reduce construction costs.

In some instances, you will find properties where both the inner and outer wall are blocks. In this case the external wall will usually be rendered.

There are several ways you can damp proof breeze blocks, and this can be done both internally and externally. Some common options include:

  • External render
  • External masonry paints
  • Internal tanking (membranes or slurry’s)
  • Also, condensation can be reduced by improving insulation

The option you choose will depend on the circumstances. For example, a single skin garage may need a different solution to a habitable space.

Are breeze blocks waterproof?

can you damp proof breeze bloks

Breeze blocks are not completely waterproof and are generally more porous than bricks and stone. This means that water can permeate through more easily. This is not a problem when block is used internally as they are not subject to weather like the external masonry.

Internally, they will also be covered with plasterboard and decorated. Unless there is an issue with penetrating damp, or an internal leak they are unlikely to meet a water source. Hence, they don’t really need to be waterproof in this scenario.

When blocks are used externally, they are usually rendered. A common example of this would be a garage or a shed. If the blockwork is exposed to driving rain it is very likely that damp will find its way through to the internal surface.

Ways to damp proof breeze blocks internally

In some cases, damp proofing internally will be your best option. There are several reasons for this, including, poor access to the external surface, or wanting to add an extra layer of protection internally.

One of the most popular ways to waterproof breeze blocks internally is using a tanking system. This can be a membrane or a slurry.

In most cases a slurry will be the best option, as it can be applied very easily. It comes in a powdered form and simply needs mixing with water. Once you have mixed the slurry, it can be placed in a bucket and applied to the surface with a stiff masonry brush.

To add an extra layer of damp-proof protection you can apply batons to the wall and fix foil backed plasterboard as your finished surface.

 Also, if you think condensation might be an issue to the surface being cold. You could opt for an insulated plasterboard instead. This combination would damp proof and insulate your internal breeze blocks.

Ways to damp proof breeze blocks externally

If breeze blocks are used in the external surface of a building, it is advised that you damp proof from the outside. A good example of a building that may have external blockwork, is a single skin shed or garage.

These types of non-habitable building are quite prone to damp for several reasons. Firstly, they are usually cold and due to blockwork being more absorbent can suffer with damp. This is especially true if they are not protected externally.

The best way to damp proof from the outside is with a render. This will need a scratch coat and then a final coat on top.

The mix you use for the render can vary depending on who you ask. Many plasterers will use 4 parts rendering sand to 1 part cement for the scratch coat and 5:1 for the final coat.

Renderers will generally use a plasticiser to reduce how water permeable the render is. Alternatively, you can add 1 part lime to the original sand cement mix. Lime is a waterproofing material that was used a lot in older period properties (before cement). It offers waterproofing qualities, as well as excellent breathability.

You can see a good video of how a sand cement and lime mix can be created and applied in the video below.

Need help damp proofing your blockwork?

For large, more skilled jobs, such as rendering you should probably hire a professional. If render is applied poorly, it can lead to future problems with damp. The result is you will end up doing the job twice and you could suffer more damage from penetrating damp.

There is a cost to hiring in skilled trades. However, you can save a significant amount by getting quotes online. By far the best way to do this is comparing quotes. Doing this means you can read reviews on a company’s profile, and you will likely get quotes from many different companies.

All these companies want the work, and they know that their competitors are bidding on the job too.

To see how much you can save by comparing local rendering companies Click Here

If you need help with any other type of damp proofing you can also compare damp companies and get free home surveys by Clicking here

Conclusion

There are several ways you can damp proof breeze blocks. Some of these can be simple DIY projects that you can do yourself, such as applying a tanking slurry, and some will require the help of a professional.

One thing you should always consider, is an expert will be able to do most jobs to a higher standard. Not only that, they will usually guarantee their work for many years (even decades).

Filed Under: Damp Proofing

Can a builder fix damp? Or do you need a specialist?

November 27, 2021 by Carl Lewis

Damp can enter a property from many different places. It can enter via defects in the walls, through leaking roofs and even rise from the ground below you.

Depending on where you find damp, you may wonder who the best person is to call. For example, can a general builder fix damp, or would you be better hiring a professional damp proofing company.

A general, residential builder should be able to help with a variety of damp issues. They will usually have broad experience in a variety of trades and may specialise in one in particular. For example: Bricklaying, joinery, etc.

However, if the damp problem is more complex, you will need to seek help from a professional damp expert.

What types of damp can a builder help with?

can a builder fix damp

There are many types of damp that a builder can help with. In fact, many jobs could even be achieved by a handyman, or even as a DIY project.

Some of these jobs would include things like:

  • Replacing cracked bricks
  • Repointing
  • Repairing damaged rendering
  • Applying damp paints and slurry’s
  • Fixing damaged guttering and down pipes
  • Resealing around windows and doors

A builder, or a handyman, could also be a good choice for internal repair work, such as re-plastering, replacing damaged woodwork and even decorating.

Generally, any issue that is causing damp to penetrate through the walls and around windows and doors, should fall into a builder’s wheelhouse.

Any of these could be achieved by either a damp proofing company or general builder. Many could even be fixed as a DIY project.

There are also some jobs that should usually be done by a specialist trade. These include:

  • Rendering an entire house
  • Roofing
  • Installing new UPVC windows and doors

A general builder may be able to do these types of jobs. However, it is usually recommended that you hire someone who specialises in the trade. After all, a bad render job is going to be very noticeable, and a leaking roof, due to a bodged job could cause a lot of damage.

The advantage with a specialist trade, is they do these jobs every single day. This means they are completely focused on this specific discipline.

When to avoid hiring a builder for damp proofing work

For a lot of jobs, hiring either a damp expert or a general builder would be fine. You may even find that the price you pay is quite similar. However, there are times when a specialist can provide extra knowledge, that is required to do the work properly. Some examples include:

Replacing physical damp proof course (DPC)

This is a specialist job and requires a certain level of skill and experience. The brickwork will need removing in sections to insert a new DPC. There will also be internal damp proof rendering and plastering that is required.

This could potentially be achieved by a builder, who is an experienced bricklayer. However, it again boils down to repetitive experience. A damp company with brickies that do this all the time, might be better than a general builder who has maybe done this job once or twice.

Obviously, there are also simple DIY options, if you decide to go down the chemical DPC route.

Basement tanking and conversion

Again, this is highly specialised work. If you intend for your basement to be a usable room, it could require a sophisticated cellar tanking system.

This could include pump systems that are placed under the basement floor. These then collect moisture from the basement via channels that collect water and direct it towards the pump. Following this, the water is pumped outside into an external drain.

This is highly specialised work, and a general builder will usually not have experience setting this up.

Full damp surveys

One of the biggest frustrations with damp, is it can be difficult to locate the exact cause. In some cases, it may be obvious. For example, a roof leak might be easy to find, and penetrating damp caused by a cracked brick, or damaged pointing is often obvious. However, this is not always the case.

Sometimes damp can find its way into your home via unusual routes. A good example of this, would be water entering high up on an external wall via a defect, but then bridging your cavity lower down. In this case the cause of damp may not be obvious.

The advantage with a specialist, is they are dealing with this type of issue every day. As a result, they will come across problems regularly, that a general builder may not.

Who will cost more damp company Vs builder?

If you are having a complex damp issue fixed it can be an expensive job. But what if the job could be done by a builder or a damp proofing company. Which is going to be the most cost effective?

In both cases you are hiring a skilled trade. Due to this, you should expect to pay a professional rate. However, one will not necessarily be more expensive than the other. The price will usually be based on the cost of materials and a day rate for the worker. Obviously, you may expect to pay more hiring a larger company, as opposed to an individual local tradesman.

The best thing you can do is get quotes from both. Make sure the quotes are for the same work and simply compare.

If you really want to save money, you can take this one step further and compare multiple quotes. Online comparison sites make this very simple nowadays, as a result you can get several local quotes for the same job, at the click of a button.

There are several advantages to this:

  1. You will get a mixture of builders and specialist damp proofers applying.
  2. People with experience in the job are most likely to apply.
  3. You can read past reviews and see similar work they have carried out before.
  4. It is a competitive marketplace. These companies will all try to compete on price.

Due to these points, you can make sure you find the right person for the job, and often save a good amount of money in the process. We have seen discounts anywhere from 20-50+% when people compare this way.

For the best place to compare local damp specialists and builders Click Here

Conclusion

Builders are experienced in a broad range of skills; due to this, they can probably help with most damp problems. However, there is a lot to be said for experience and a damp specialist will have much more focused knowledge. Because of this, they are usually the best choice for more complex damp proofing jobs.

It is also worth noting, that most damp-proof companies will offer guarantees for the work carried out. These can often be up to 20+ years guarantee. You may not get this type of assurance from your local builder

Filed Under: Damp Proofing

Is a properties DPC above air bricks or below.

November 22, 2021 by Carl Lewis

There are many precautions taken in a property to protect it from damp. One of the most common we hear about is the DPC (damp proof course). This is a layer of damp-proof material that forms a continuous waterproof barrier in mortar joints at the base of a property.

The DPC is commonly found around 150mm above ground level in external walls. Also, in the internal skin of cavity walls, there will be a DPC found slightly below floor level.

Another common cause of damp is poor ventilation. This happens when moisture becomes trapped in a property. When this happens, it increases the risk of damp, mold, and rot.

When we think of trapped moisture in a property, we often think of condensation building up inside the home. However, moisture caused by rising damp and penetrating damp, can also be made worse if there is poor ventilation.

dpc above air bricks

Therefore, properties have air bricks installed. An air brick is roughly the same size as a standard house brick, the difference being that it contains holes. These holes allow air to circulate in the cavity and below floor voids.

Air bricks can be installed either above, or below a properties DPC. It is more common to see them lower in properties that have suspended timber floors, with a void beneath.

Timber joists with a void just above ground level, are prone to condensation, and potential issues with rising damp. This means they benefit greatly from extra ventilation and clean air circulation.

Without airbricks, the chance of damp, rot, and other issues, such as woodworm infestation become greatly increased.

Can Air Bricks Cause Damp?

The main goal of an airbrick is to reduce damp by venting the area. But there are a few instances where they could create damp problems. This is rare, but it can happen.

Regulations state that an airbrick should be installed at least 75mm above ground level. If the airbrick is below this, it has a much greater chance of allowing water to enter the cavity. This can also be increased, if the ground outside slopes towards the property, or if the area is prone to flooding.

However, at 75mm above ground level, you are more than likely below the properties DPC. Therefore, even if water enters through the ventilation holes, it shouldn’t be able to rise above internal floor level. This could be affected by the level of water entering and the potential of a blocked cavity.

Things you need to check

If you do notice internal damp near an airbrick, these are the things you need to check:

  1. Is your airbrick less than 75mm above ground level? – This could be the result off raised floor level outside, due to something like a patio, raised beds or decking.

  2. Is there damage to your DPC? – If you do think there is damage, then you would probably benefit from an injectable DPC. These are relatively inexpensive and DIY options are available. You can read more about our favourite DPC cream here.

  3. Check your cavity for blockages. – Ideally, you would expect the cavity to extend at least 250mm below the airbrick. If material and debris collect in the cavity, this could increase the chances of moisture rising past your DPC. If this happens, moisture could bridge the cavity into your property.

  4.  Check the airbrick for blockages. – It is more likely that the airbrick causes damp, due to it not doing its job properly. If the vents become blocked, air will not be able to circulate. As a result, moisture will remain trapped, and this can cause all kinds of problems, such as worsening damp, mold, and rotten timbers.

If you do have damp and none of the above seem to be the cause, then you should probably speak with a damp-proof expert. A professional will be able to inspect the issue and find the exact cause of your problem.

Ideally, you should use an online comparison site to compare damp proofing companies. This is the most cost-effective way to hire. Also, it allows you to read previous customer reviews, so you hire a reputable company.

To see our favourite comparison site for damp proofing Click here and get up to 5 local damp quotes

TIP: Most companies will come out for a free inspection.

Can you seal airbricks?

Sealing up airbricks is nearly always a bad idea. Especially if they are original and were installed when the property was build.

The airbricks are there to provide needed ventilation for your home. Without them, you are likely to suffer with greater internal condensation. It could also cause damage to structural timbers over the long term. If timbers are damp and unable to breathe, it will drastically increase the formation of mold and rot.

Generally, air bricks will be placed in several locations around your home. Based on current regulations you will usually find one on each external wall of your property. This is a to provide even ventilation throughout the cavity and under floor voids.

In properties that have solid ground floors you may find vents higher on the wall. This is very common in ex local authority properties, where the ground floor is not a suspended timber floor.

When the vents are higher, they will often have an internal vent inside your property. These can occasionally cause a draft and it may be tempting to cover them. However, it is possible to simply block the draft with an adjustable air vent cover.

Also, if the airbrick is in a high moisture area such as your kitchen or bathroom, you could install an extractor fan. By using a fan to extract moisture, you have no need for an internal vent in that room. In this case, you could leave the external air brick to ventilate the cavity, and the extractor fan would deal with any internal moisture.

Conclusion

Air vents are installed in most properties and offer a needed means of ventilation. There location on a property can vary, can range all the way from 75mm above ground level. All the way up to below the roof level.

They can be placed above or below a DPC. The vents’ location will usually be based on the type of property.

Filed Under: Damp Proofing

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