Patio Sealing: What Homeowners Ask the Most

You’ve put effort and money into building a patio that fits your lifestyle. It looks attractive, feels comfortable underfoot, and may even add value to your home. But once it’s finished, one of the biggest questions is — do you really need to seal it?

Sealing isn’t always essential, yet many homeowners choose to do it for the added protection it provides. Whether your paving is natural stone, concrete, or porcelain, a good patio sealer can help guard against weathering, stains, algae, moss, and everyday wear.

This guide answers the most common questions about patio sealing, giving you practical advice on whether it’s right for your paving. Use it as a starting point to understand the main benefits, potential downsides, and the process of keeping your outdoor space protected and looking its best.

Patios face constant exposure to weather, footfall, moisture, and fallen leaves or debris. Over time, these elements can gradually wear down paving — particularly if it’s made from porous materials such as sandstone, limestone, or concrete.

Leaving paving unsealed won’t ruin it straight away, but it does leave the surface more at risk over the years. Porous stone can absorb water, which encourages moss, algae, and black spot growth. Spills from BBQs, plant pots, or food are also harder to remove without a barrier in place. In colder months, freeze-thaw cycles can cause small cracks to appear — especially in stone that naturally soaks up moisture.

The look of your patio is another factor. Without sealing, natural stone can lose colour or develop uneven patches, particularly in high-use areas. This kind of wear can make a patio appear older and more worn than it really is.

Here’s a summary of the typical issues that arise when patios are left unsealed:

In short, not sealing your patio means you’re leaving it exposed to the natural environment with no buffer. While this might be fine in the short term — especially for low-traffic areas — it’s important to weigh that against the extra time, effort, and cost of cleaning or restoring it later.

Sealing a patio isn’t always mandatory — but in most cases, it’s a worthwhile step. It shields the surface from staining, weather exposure, algae growth, and UV fading, all of which can make paving look older before its time.

For patios built with porous stone such as sandstone or limestone, sealing is especially valuable. These materials naturally absorb moisture, dirt, and organic deposits, which can lead to permanent marks or colour changes. A quality patio sealant creates a breathable barrier that simplifies cleaning and helps the paving last longer.

Sealing is also a smart choice if you’ve recently laid new paving or carried out a professional clean. It locks in the fresh appearance and protects the finish you’ve invested in.

Where sealing makes the biggest difference:

Yes — and many people do. As long as your patio is in decent condition and you follow the correct steps, sealing it yourself is a simple weekend project. It doesn’t require specialist tools, and with a little preparation, you can achieve a professional-looking finish.

Here’s what the process typically involves:

1. Clean the patio thoroughly
Dirt, algae, black spot, or leftover jointing compound should all be removed before sealing. A pressure washer and patio cleaner make this easier. If you seal over dirt or damp patches, they can become trapped beneath the surface.

2. Allow it to dry completely
This is often the most overlooked step. Even a little trapped moisture can cause patchiness or blooming under the sealant. Let the paving dry for at least 24–48 hours in good weather.

3. Choose the right sealer for your surface
Some products are formulated for sandstone or limestone, others for porcelain or concrete. You’ll also want to decide between a natural finish or a colour-enhancing one.

4. Apply evenly with a sprayer or roller
Use a pump sprayer for larger areas or a roller for smaller patios. Avoid pooling and work methodically in sections. Wear gloves and mask off any surrounding plants or borders.

5. Let it cure undisturbed
Keep off the area for 12–24 hours, depending on the product instructions. Avoid rain during this time — dry, still days are ideal.

Tip: Always test the product on a small, hidden area first to make sure you like the finish.

Weeds are a common frustration for anyone with a patio. They tend to pop up between joints, along edges, and anywhere they find a gap. So, does sealing your patio actually stop them?

Not entirely — but it does help reduce them.

How sealing helps with weed control:

• Fewer gaps to take root in: A sealed surface reduces the porous entry points where seeds and debris usually settle.
• Drier conditions between joints: Weeds thrive in damp, gritty joints. Sealing keeps moisture out and deters growth.
• Easier to clean regularly: When your paving is sealed, sweeping away early weed growth is much easier.

While sealing won’t completely eliminate the chance of weeds, it works best as part of a broader maintenance approach — combine it with a proper jointing compound and the occasional power wash, and you’ll seriously cut down on the problem.

Natural stone patios

Natural stone is more porous than porcelain, meaning it absorbs moisture easily and is more prone to staining, algae, and frost damage.

Sealing is essential to help protect the surface and extend the life of the stone, especially with softer types like sandstone.

Most natural stone patios should be resealed every 2–3 years, though this depends on how exposed the area is, the type of sealer used, and the stone itself.

You’ll know it’s time to reseal when water no longer beads on the surface or when black spot becomes harder to control despite regular cleaning.

Porcelain patios

Porcelain is far less porous than natural stone. It doesn’t absorb moisture easily, which makes it more stain-resistant from the start.

Sealing porcelain is optional — and when done, it’s usually to protect the grout or pointing rather than the tile itself.

If you do seal porcelain, it may only need refreshing every 4–5 years, or even less frequently depending on the product used.

It’s important to make sure the patio is ultra clean before sealing, especially the joints — once sealed in, dirt can become a permanent feature.

Block paving is one of the most popular choices for UK driveways and patios. It’s durable, easy to lay, and looks smart — but it’s also notorious for weed growth and colour fading. So should you seal it?

In most cases, yes — sealing block paving offers a practical way to protect both the surface and the sand-filled joints.

Why sealing helps with block paving:

• Stops joint sand erosion: Rain, wind, and traffic can wash away kiln-dried sand between blocks. A sealer helps lock it in.
• Reduces weed growth: Once the sand is stable and sealed, weeds have fewer places to take root.
• Slows down colour fading: UV light gradually lightens block colours. A good sealer offers some UV protection.
• Improves stain resistance: Oil spills, bird droppings, and rust marks are easier to remove from sealed surfaces.

Sealing also brings out the colour in many block types, making the area look cleaner and more uniform — especially on older drives that have started to look patchy.

The success of your patio sealing job doesn’t just depend on the product — timing matters just as much. Applying sealer in the wrong conditions can lead to poor performance, patchiness, or even trapped moisture.

The best time? Late spring to early autumn.

You want dry weather, mild temperatures, and low humidity — conditions that help the surface dry fully before and after sealing.

Here’s a quick seasonal breakdown:

Key conditions to check before sealing:

• Dry weather window — Aim for at least 48 hours of dry conditions both before and after application. This ensures the patio is fully dry before sealing and gives the product time to cure properly without rain or excess moisture interfering.
• Temperature range — The ideal daytime temperature is between 10°C and 25°C. Sealing outside this range can affect how the sealant bonds to the surface, either drying too quickly in heat or struggling to set in cooler weather.
• No frost or heavy dew — Overnight frost, dew, or damp air can compromise the finish, leaving cloudy marks or reducing effectiveness. Always check the forecast to be sure the surface will stay dry while the sealer hardens.

Taking a little extra care with timing helps make sure your patio sealing lasts longer, gives even coverage, and delivers the best possible protection.

Getting the right quantity of sealer makes all the difference — too little leads to patchy results, while too much means unnecessary expense. Luckily, working it out is straightforward once you know the size of your patio and the sealer’s coverage rate.

Step-by-step guide:

1. Measure your patio
Work out the total surface area by multiplying the length × width (in metres). Example: 8m × 4m = 32m².

2. Check the product coverage
Look at the instructions on the label. Rob Parker’s Best Patio Sealer typically covers 6–8m² per litre, per coat, depending on how porous the stone is.

3. Factor in the number of coats
Most natural stone patios will need 2 coats. Porcelain, being less porous, may only need 1.

4. Do the calculation
Take your total m², divide by the coverage rate, and then multiply by the number of coats required.

1. You’ll need just under 10 litres — so you’d likely buy two 5L tins.

Pro Tips:

• Porous stone like sandstone may absorb more — expect closer to 6m² per litre.
• Always read the tin — not all sealers have the same spread rate.
• Test a small area first — especially if your patio has mixed stone or patch repairs.

Suggested image location: diagram showing patio dimensions with two sealed coat layers visualised.

Buy Patio Sealer

1 litre: £38.00 + VAT | 5 litre: £175 + VAT

Sealing Granite

Granite is one of the hardest natural stones, making it highly resistant to everyday wear. However, it’s still exposed to the elements — and in the UK, constant rain, frost, and algae can cause gradual damage over time.

Sealing granite helps protect it by repelling water, oils, and grime. It also reduces the buildup of green algae and black spot, making general maintenance much easier, especially in shaded or damp areas like pool surrounds.

Because granite is so dense, it won’t absorb as much sealer as more porous stones. Use a breathable product and apply it thinly to avoid overcoating.

If you want to keep the stone’s natural matte appearance, choose a neutral, non-enhancing sealer.

Sealing Quartz

Quartz — whether engineered or resin-bonded — is often chosen for outdoor areas where a polished, high-end finish is desired. It’s naturally resistant to staining, but sealing can offer added protection against UV fading and long-term weathering.

Sealing quartz helps guard against discolouration and residue build-up, making regular cleaning easier and less abrasive. It also supports the long-term preservation of its sleek, polished appearance.

Not all quartz finishes absorb sealers evenly, so it’s important to carry out a spot test before applying it across the entire surface.

Buy Quartz and Granite Sealer

500ml: £19.50 + VAT

Sealing your patio doesn’t need to be overwhelming — and whether you’re cleaning, protecting, or maintaining your paving, the right approach makes a big difference over time.

If you’ve got questions about which sealer to use, how to apply it, or what’s right for your specific stone — we’re happy to help.

We stock sealing products that are simple to apply and made for British conditions — so whether you’re looking to protect fresh paving or revive old stone, you’re in the right place.