Crownstone Group

Crownstone Group We deal with wherever you DON'T want water.

06/08/2026

One of the biggest mistakes I see with external balconies is where the insulation is placed.

Quite often, the insulation sits directly beneath the waterproofing layer.

The problem?

Once water gets behind that waterproofing, the insulation essentially acts like a runway, allowing water to travel across the balcony until it eventually finds a defect or opening into the building.

Using the shower/wet room analogy might sound silly, but I've found it to be one of the best ways to explain how to correctly waterproof a balcony.

When we build a shower correctly, we don’t just waterproof the tiles. We waterproof the room beneath them as well.

Balconies should be approached in exactly the same way.

The top waterproofing layer protects the balcony surface itself, whilst the secondary waterproofing below protects the structure and keeps the insulation dry.

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Crownstone - Dealing with wherever you don't want water.

[email protected] | 020 8226 5654

04/08/2026

Obviously we're not saying your bathroom plant is causing condensation…

…BUT we are saying watering something in a warm humid room probably isn’t the silver bullet you were hoping for 🌿😅

If your bathroom has no windows, proper mechanical ventilation is usually the answer.

We're big fans of continuous running extractor fans for this sort of scenario. Quiet, consistent and actually moving moisture out of the building rather than just hoping it disappears on its own.

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Follow us Crownstone, for more practical advice on dealing with damp, condensation and waterproofing!

30/07/2026

This is why the damp industry gets such a bad reputation.

This homeowner has spent THOUSANDS on damp injections for a property that didn’t even need them.

To add insult to injury, the injections had been drilled into the wrong place anyway.

So "what was the issue?" we hear you ask...

A porous chimney.

Water was travelling down the chimney breast, hitting the damp course, then spreading sideways through the property.

This is the problem with not taking time to understand a property and the presenting symptoms, instead many will just apply a “one-size-fits-all” damp solution because it's easier! (and they can charge more!)

Not every damp patch is rising damp.
Not every house needs injections.
And not every salesperson is a surveyor.

Sometimes people just need an honest diagnosis instead of being sold the most expensive option.

Please stop ripping people off.

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Crownstone - Dealing with wherever you don't want water.

[email protected] | 020 8226 5654

28/07/2026

A really good point was raised in the comments on one of our recent videos:

“It’s why mechanical ventilation is so important, it’s verifiable"

And we completely agree.

Mechanical ventilation gives us something measurable. We can verify how much moisture is actually being removed from the air in a building, rather than hoping conditions are doing the job for us.

With “unchecked” ventilation, like air bricks or trickle vents, we’re relying on outside temperatures, wind direction, pressure differences and occupant behaviour. Sometimes it helps. Sometimes it doesn’t. But it’s very difficult to actually quantify.

That’s the key difference.

Good building diagnosis should be based on what we can measure and the evidence we can gather, rather than guesswork.

Now, that doesn’t mean every building automatically needs a full mechanical system. Every property behaves differently depending on its construction, occupancy and moisture load.

But when condensation and mould become persistent problems, controlled ventilation is often a far more reliable solution than simply “opening a window and hoping for the best.”

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Crownstone - Dealing with wherever you don't want water.

[email protected] | 020 8226 5654

23/07/2026

Did you know it isn't just heat that makes buildings move.

Water does too!

When building materials become saturated, they swell, and as they dry out, they shrink.

Then the sun comes out and they expand again through thermal movement.

So your building is constantly moving.

Expanding. Contracting. Swelling. Drying.

And over time?

Cracks appear and water will find a way in.

This is exactly why waterproofing should not be treated as a job done exercise.

We see it all the time:
“A basement was waterproofed 10 years ago, so it should still be fine.”

That’s a bit like saying you serviced your car once and expected it to last forever.

Waterproofing systems need maintenance because buildings are moving structures. Thermal expansion and moisture movement are part of a building’s life cycle.

Good waterproofing isn’t just about an incredible install, it’s about understanding building pathology, movement and having a long-term maintenance plan in place.

Because eventually, every system will need attention.

The question is whether you catch it before the water does💧

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Crownstone - we deal with wherever you don't want water.

Drop us an email or give us a call: [email protected] | 020 8226 5654

21/07/2026

When it comes to waterproofing, not every structure is designed to the same standard.

Especially underground structures!

In this scenario, the structure only required Grade 1 waterproofing — meaning some water is acceptable, provided the space still functions as intended and doesn't fill up with water!

The structure itself is a Type B waterproofing system, where the reinforced concrete acts as the waterproof barrier.

But here’s the common issue with Type B systems:
The joints.

You may have 250mm+ of waterproof concrete… but the joint itself is often relying on a much smaller waterbar detail buried within it.

That’s why joints are usually the failure point.

In this case, the waterbar had failed after only 8 years, allowing water to track through the joint, allowing for lime deposits to build up as it migrated through the structure.

The repair involved filling the full depth of the joint with waterproofing material, rather than relying on a small embedded detail alone.

A good example of why waterproofing failures are nearly always found in the details.

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Crownstone - Dealing with wherever you don't want water.

[email protected] | 020 8226 5654

16/07/2026

This isn’t rising damp.

As you can see, this air brick on a Victorian home is bridging the damp course.

So when it rains… the water finds its way in and under the building.

Into the timbers.
Into the walls.

As expected, someone called it rising damp.

But they are wrong!

This is what happens when you treat symptoms instead of understanding the building.

In this scenario, the water is just following the path it was so kindly given!

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Crownstone - Dealing with wherever you don't want water.

[email protected] | 020 8226 5654

14/07/2026

Water was here before us.

Before buildings.
Before materials.
Before “solutions”.

So let’s get one thing straight…

We’re not building in a dry world where water is the problem.
We’re building in water’s world.

And that changes everything.

If you don’t understand how water behaves; how it moves, tracks, finds its way into where you don't want it.

You will never keep a building dry.

This is what building pathology is really about.
Not guessing. Not slapping products on.

Understanding the cause.

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Crownstone - Dealing with wherever you don't want water.

[email protected] | 020 8226 5654

09/07/2026

Water doesn’t need an invitation… it just needs a weakness.

Here, it was external balconies feeding water straight into expansion joints and from there, right into the lift shaft.

Now the problem:
Expansion joints are designed to move, we couldn't go in and “seal” them.

So we designed a solution using Koster Aquatecnic Ltd S4 acrylic gel. It's flexible, bonded, and actually works with the building, not against it.

Result?
A joint that still moves… but no longer allows water in.

Job done ✅

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We are Crownstone Group and we deal with wherever you don't want water!

07/07/2026

What actually is relative humidity?

Very simply:
It’s the amount of moisture the air can hold at a given temperature.

👉 Hotter air = more moisture capacity
👉 Colder air = less moisture capacity

That’s why cold winter air outside is actually quite dry.

But when you heat your home, you increase the air’s ability to hold water so the vapour pressure goes up.

If that moisture doesn’t leave?

It builds up.
Day after day.

Until you’ve got the perfect conditions for mould.

No fancy kit needed, just an understanding of how your building behaves.

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Crownstone - Dealing with wherever you don't want water.

[email protected] | 020 8226 5654

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