Can Patio Go Above Damp Course? (The Correct Answer Is Here!)


Can Patio Go Above Damp Course

For many drainage and paving projects, defining the damp-proof course level is essential to establishing the drainage and paving at the correct level. With that in mind, many apartment owners wonder, “Can a patio go above a damp course?”

This article will give you the exact answer to this question. Also, we will walk you through how to seal a patio. So let’s scroll down to see more!

Can Patio Go Above Damp Course?

No. The patio can’t go above the damp-proof courses (DPC). Instead, DPC must be at least 150mm above the ground or pavement.

It will ensure a minimum elevation above standing water that may occur in heavy rain or other problems, such as allowing the hosepipe to run unchecked.

According to the Building Regulations, the DPC must be at least 150mm above the ground and any paving.

Yet, there are some situations where it is impossible to maintain this regulation. 

Regarding professional work and new build projects, you must ensure that this “150mm” rule is not breached.

However, when it comes to domestic, small projects, like a patio or driveway, there are situations where keeping the paving under DPC 150mm would involve a vast amount of work that can’t be justified. 

In these cases, you can “bend” the 150mm rule a little, but make sure the obey following provisions:

  • Bend the 150mm rule only applies to private properties, never to commercial or public properties
  • You need the consent of the property owner to the breach.
  • In all cases, the ground or paving level should be at least 75mm below the damp-proof course. Anything less than it will lead to trouble.

Also, you must remember that bending this 150mm rule can lead to a reduced building valuation or a  requirement for remedial work. 

So how to determine DPC on a building? In some cases, identifying the DPC is fairly straightforward, as it protrudes a bit from the bed joint, allowing easy identification, even for the blind, thanks to the fingers. 

But, in other cases, it might be less obvious and require some investigating and poking about to pinpoint its position.

Where the DPC does not protrude to announce its presence, some key indicators can help you identify its position.

  • Regarding many established properties, the DPC will typically be somewhere from 100 mm to 450mm above the ground or paving level.
  • Air bricks are commonly (but not always!) directly below or above DPC.
  • There is often a difference in brick appearance or type at the DPC.

So, as you can see, in no case is the patio above the damp course.

A Step-by-Step Guide On How to Seal a Patio

Sealing a patio will restore its natural beauty and protect the paving against the damaging effects of erosion, weed, weathering, and other natural aggressors.

Step 1: Seal a Test Area

You should start by sealing an inconspicuous area. 

That way you can see what the finish will look like once it’s done. Thanks to that, you can decide to change your choice in time.

You can experiment with paving slabs behind the shed or wheelie bins. Just test it and let it dry before checking it again in a few days.

Step 2: Consider Weather Conditions

Do this project on a dry, sunny day. Rain is really the enemy of drying glue.

If you seal a slightly damp or wet surface, it will result in a ‘blooming’ effect.

It refers to the water reacting to the patio sealer and will spoil the slabs if left to persist.

Summer is usually a better time to seal a patio. So you should do it in July or August for the best results.

Step 3: Preparation

You need to start by wearing protective glasses and gloves and keeping pets and children away from the work area.

Sealant is almost not feasible to remove when it is freshly applied. So once your patio is completely dried, it is time to clear the area.

The sealing process will ‘lock in’ the debris and dirt left behind. The same also goes for any weeds and tough moss. 

For this step, you must dig the worst greenery using a spade and clear the surface with a stiff brush.

This step also includes moving any garden furniture, such as potted plants, out of your patio unless you only have to seal your patio partially.

You also need to look around to see if there is any damage. Chips and cracks, or any sinking stones, must be taken care of before sealing. 

Step 4: Cleaning the Surface Of Your Patio

After inspecting your patio for debris, weeds, and any other growth and ensuring your patio is completely clear, now is the time to clean it.

For badly stained, using a specialist paving cleaning solution might help, but you must obey the instructions. Aim for products made for your paving types.

You can also use a pressure washer for this step. It is not necessary to spend a lot of money to buy one. Instead, you can rent for much less.

Then let your patio dry entirely for at least three days.

Step 5: Re-Joint

When cleaning your patio, you may accidentally blast mortar and sand out of the joints. In this case, you must apply jointing sand before sealing your patio.

Various re-joining products are available for you to choose from to get the right results. In some cases, one jointing compound might be your best bet, but using an epoxy mortar and kiln-dried sand in others is okay.

Re-joint is an indispensable step in this process. If the joints are not adequately compacted, the slabs will begin sinking, leading to a loss of balance.

Step 6: Apply Paving Sealant

Sealing products can vary in usage. It is, therefore, essential to carefully read the instructions for use that come with your product. You can get the job done with the help of a fiber-rolling brush or a sealant sprayer.

Based on the manufacturer’s instructions, fill your sprayer to the recommended product/water ratio. However, depending on your preferences and specific situation, you can change this ratio.

Remember that the key is consistency. When you spray, you will need to do it in uniform circles and make sure to cover your entire area.

Start with the corners and edges before moving inwards. A paint roller might be helpful in this step.

Step 5: One Coat or Two Coats?

It is not always good to apply a second coat when sealing a patio, and some manufacturers don’t advise it on their products.

However, second and third coats usually deliver an extra sheen or gloss and extra protection. 

It allows you to lock in color on the first coat and improve it on the other.

Furthermore, the first layer mainly protects your patio, while the second layer will typically add protection and slightly change its look.

Therefore, some manufacturers will recommend a second coating to highlight the color. In some cases, completing a second coat is necessary.

Step 6: Give It Time To Dry

After completing the above steps correctly, give your patio sealer enough time to dry before releasing the pet or walking around.

It usually won’t take too long, and you can expect your patio sealer to dry completely in three hours.

However, if you will apply a second coat, you should not wait for it to dry before starting. Otherwise, your additional coats will not be able to soak into the stone.

Once everything is done, the longer you leave your patio, the better it will be. Ideally, you leave it on overnight and witness excellent results the next day.

Which Patio Sealers to Use?

Sealants for patio stones are available in different varieties, which can be overwhelming to choose from. So you can check out our top picks. 

Indian Sandstone

Natural stone has a reputation for being notoriously porous, meaning your chosen product must be able to be soaked and impregnated in deep.

Our pick, Natural stone sealers of StoneCare4U’s, will work great for sandstone.

Concrete Slabs

Resiblock is our favorite all-around brand for sealing concrete slabs.

Its water-based acrylics will protect slabs well against the sun and everyday weathering. They minimize yellow patches that can happen with cheaper stones.

Block Paving

Regarding block paving, we favor matte & wet look patio sealer products from Resiblock. 

Close Thoughts

You have reached the bottom of this article. Hopefully, you will find it useful. We still have lots of great tips and valuable guides related to patios. So don’t miss them if you have time.

Thanks for your attention!

James Lopez

James Lopez is a lifestyle journalist. In addition to working as a journalist, he also takes courses in landscape design. He is pretty focused on the outdoor space, especially the backyard.

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