How To Clean Block Paving With A Pressure Washer

Once your stunning block paved driveway has been laid down for some time, you will begin to notice that it doesn’t look quite as aesthetically pleasing as when it was first installed. Being exposed to the elements and heavy traffic, it doesn’t take long before block paving needs a good clean. 

But did you know that using incorrect techniques may actually cause irreparable damage to the stones, leaving you with a hefty replacement bill. On the other hand, using too gentle cleaning methods won’t remove those stubborn marks so what is the best way?

A pressure washer is an incredibly useful piece of equipment when it is put into the right hands. Of course, you could hire a pressure washing company to do the hard work for you but in this day and age, it’s all about being thrifty. Doing it yourself is certainly going to save you a pretty penny and it isn’t as challenging as you might first think. 

Does Pressure Washing Damage Block Paving?

Pressure washers are amazingly powerful tools that are designed to remove even the most stubborn marks and stains from outdoor surfaces. This need means that they must fire extremely high pressure jets of water to blast away things like oil stains and ingrained dirt. 

However, since the stones used on your block paved driveway are delicate, this high pressure could damage them or cause them to crack, if you don’t do the job properly. Another serious problem that can occur is when water becomes lodged underneath the blocks which in turn, will disrupt the driveway bed causing it to shift. More often than not, this happens if you use a pressure washer on your block paving too frequently.

For this reason, we would always suggest that you err on the side of caution and only pressure wash your block paving when it is absolutely necessary. There are other methods of cleaning that you can use that will deliver excellent results and don’t come with the risk of damaging your property. 

In addition to damaging the block paving, there is also a chance of a process known as efflorescence occurring. This is where white marks appear on the surface of the driveway owing to salts being released from the stone during cleaning. Typically, this happens on newer block paving so it may be best to avoid using this type of cleaning until the driveway has had time to naturally disperse any salts. 

Important Things To Consider When Using A Pressure Washer To Clean Block Paving

Having read through some of the risks of pressure washing your block paved driveway, you might be instantly put off the idea. But don’t let these things deter you; provided that you are cautious and take a responsible approach to cleaning, your driveway shouldn’t suffer – nor should your bank account!

There are risks involved in anything and ensuring that you don’t pressure wash too often is one of the first and most important things to consider, as we have already discussed. Secondly, you must think about the way in which you use your pressure washer on the surface of the pavers. This type of cleaning can and will blast out dirt from between the stones and will remove stubborn surface stains. However, it is this type of cleaning that is more likely to cause damage. For this reason, we would suggest only using pressure washing at its gentlest and for rinsing as opposed to stain removal and blasting. 

You will also need to think about the jointing sand that lies between the blocks. This is there to provide strength and structure to the driveway. If it is removed, then the driveway will become much weaker and won’t hold in position. The problem with using a pressure washer is that you may, intentionally or unintentionally blast this sand away. A lot of people believe that using a pressure washer to remove dirt and weeds from in between the paving blocks is a good idea, but at the same time, it’ll remove the sand.

Repeated use of this cleaning technique will dislodge the sand and without pulling up the entire driveway, you won’t ever get that structural integrity back. In turn, this will cause the driveway to move and potentially sink, particularly if water becomes lodged underneath.

How Often Should I Clean My Block Paving?

The frequency of block paver cleaning will largely depend on the environment in which it is laid. For example, if you live in an area with a lot of overhanging trees and bad weather, then the driveway is likely to become dirty more quickly. Moreover, driveways that experience a lot of heavy traffic will require more regular cleaning than those that are barely used. 

However, as a general rule of thumb, it is recommended that you give your block paving the once over every six months. It might be a good idea to schedule this in as part of your exterior maintenance which most people do at the beginning of spring and then again once autumn begins to set in. You’ll probably want to give your block paving a spruce up after winter because this will remove any dirt that has accumulated during the winter months. What’s more, cleaning it during the autumn will ensure greater safety as there won’t be any slippery areas on the surface when things start to freeze over. 

How Can I Pressure Wash My Block Paving Without Causing Damage?

Pressure washing your block paving should only be done when it is absolutely necessary. Even when doing it infrequently, you will still need to apply extra care and caution and the following steps will make sure that as little damage as possible is caused. 

Clear The Area

A lot of homeowners think that their pressure washer is the ideal tool for removing weeds and other debris from the driveway. But this is not the case. Before you can pressure wash the surface,you will need to ensure that it is clean. 

You’ll probably need to set aside a good chunk of time for this part of the clean and we would recommend using tools like weed removers to make the job easier. It is also a good idea to give the area a good sweep to remove dust, dirt and anything else that may have settled on its surface. 

Think About The Direction You Will Clean In

When you are using a power washer, you will need to think about where you are aiming the spray. These tools are designed for use on horizontal surfaces and never vertical ones. For example, if you were to employ a professional exterior cleaning, they would only ever use a method known as soft washing on things like house walls, roofs and windows. For this reason, you should always aim to point the spray away from your home, car and other structures.

In addition to this, you will want to avoid any splashback onto the doors and windows of your home which can happen when using a pressure washer. In the event that this does happen, we would suggest rinsing as you go to avoid a bigger cleanup at the end. However, there are attachments that you can use with your pressure washer that direct water more easily to only the areas you want to clean. 

Moreover, you should plan the clean before beginning. The last thing you want is to start at one corner of the driveway only to find that dirty water is running all over the parts you have already cleaned. Most driveways will have some sort of incline. In a lot of cases, this might not be immediately noticeable but for the purposes of drainage, there will be even a very slight incline so it is worth working out which way this goes and starting in the opposite corner to ensure dirty water runs away from the drive. 

Cleaning Solutions

In the case that your driveway is particularly soiled, using a pressure washer alone may not be enough to cut through the dirt. Later on, we will talk about oil stains which are incredibly common on driveways. However, even for less severe dirt, it may be necessary to first use some kind of cleaning solution. 

There are some cleaning solutions that are designed specifically for block paving and are eco friendly so are considered to be much better than using household chemicals. Although, if you need to, these can be used instead. The benefit to using special block paving cleaners is that many of them will also prevent moss and weed growth over time. 

Once the solution has been applied, you may have to use a little elbow grease on very stubborn stains and this can be boosted by using a thick-bristled brush. In many cases, this cleaning method will be enough and may even help you to avoid having to use a pressure washer at all. 

The Right Technique

When it is time to rinse away your cleaning solution or, if you haven’t used one, to simply clean the driveway using the pressure washer, you will need to make sure that you use the gentlest setting possible. We cannot reiterate enough that blasting the driveway on the highest pressure will do more harm than good. 

It is best to keep the lance at least eight inches away from the surface of the driveway when cleaning but you should also make sure to apply the water jets at an angle. The best option is to hold the lance at a 30º angle although, if need be, you can increase this to a 45º angle. Moreover, you should NEVER direct the water spray at the joints as this will quickly blast away the jointing sand. 

As we have mentioned, it is best to start in one corner of the drive but you should make sure that you give an even coverage. The last thing you want is a stripy driveway once the water has dried up. Gently sweeping the pressure washer across the blocks is the best approach.

Cleaning Up The Aftermath

For driveways that are very dirty, there may be a lot of moss, debris and other bits that need to be disposed of. It is possible to sweep these onto some grass but the best way to handle the mess is to sweep it up and dispose of it in the compost bin. Furthermore, if the dirt has spread out onto the pavement or another public area, you have a responsibility to get rid of it, so make sure that you include this as part of your cleanup. 

Now all that is left to do is to allow the block paving to dry. Provided that you have followed the correct cleaning techniques, you should be left with an evenly clean area that hasn’t sustained any damage. 

Many sources will tell you to replace any lost jointing sand and while this can be done, it is important to keep in mind that this will only help if a very small amount of sand has been blasted away. If you have used high pressure and lost a lot of sand, you may need a professional to come in a restabilise the driveway. 

A Note About Oil Stains

One of the biggest problems faced by homeowners when trying to maintain a visually appealing driveway is the oil stain. If your car springs an oil leak, you might not even notice until the liquid is splattered all over your once beautiful drive.

Now, yes, we will admit, it can be incredibly tempting to pull out the pressure washer and blast the stain into oblivion but this will only cause further damage to the surface and the underside of the driveway. The best option here is to take a gentler cleaning approach. This may take a little more effort but it will be worth it in the long run. 

You will first need to ensure the driveway is clear of any debris and then apply a strong washing up liquid mixture along with a degreaser. This can be worked into the stain, left for a period of time if needed and then gently rinsed away. 

Conclusion

Block paving is one of the most common types of driveway in the UK. It is durable, attractive and relatively affordable. However, keeping it clean is a must if you want it to always look its best. 

While you can use a pressure washer on your block paving, it is vital that you take the right approach because using this type of equipment incorrectly can lead to damage which could be costly to repair.