DAMP - AND WHY “RISING DAMP” ISN’T ALWAYS THE VILLAIN

Yes, rising damp is real.

But before you throw thousands at injections, take a breath.

My new neighbour found damp in his sitting room.
He did what most people would do—called a damp company.
They came over, looked around, and told him he needed cream injections in the internal and external walls. “Absolutely vital,” they said. Then handed him the quote.

Luckily, he mentioned it to me before signing anything.
I suggested he do a bit of detective work first.
We lifted some floorboards. We checked the vents.
Turns out the air bricks were blocked. Even worse—when he poured water into the drain under the downpipe, it flowed straight into the building.

Blocked drain. Blocked airflow.
The damp had nothing to do with rising water from the ground.
But if he hadn’t checked, he would’ve paid thousands for a treatment he didn’t need.

I’m sharing this because damp is complicated.
And “rising damp” gets blamed far too often—usually by people selling treatments.
Some say it’s a myth. Others blame it for anything that looks damp near a skirting board.
The truth is more nuanced.

Yes, rising damp is real. But it’s rare.
It happens when groundwater moves up through the wall by capillary action, carrying salts that stain and damage plaster, paint, or flooring.
But it only happens when:

• There’s no damp-proof course, or it’s been damaged

• The ground outside is unusually wet and high

• There’s no other drainage or ventilation issue at play

In most properties, damp has other causes:

• Blocked drains or gutters

• Poor ventilation

• Soil and debris in wall cavities

• Ground levels too high

• Defective pointing or masonry

• Cavity wall insulation gone wrong

• New floor layers trapping moisture in

The point is: treatments only work if the diagnosis is right.

If you see damp, don’t rush to inject or replaster.
And please don’t rely on someone who’s also selling the cure.

If you really want to know what’s going on, get an independent surveyor or building pathologist—someone who doesn’t sell products.
They’ll test mortar samples and salts, not just wave a two-pronged meter near the wall.

I’m not a surveyor. I’m not a damp expert.
But I’ve worked with enough old buildings to know:
If you start with the wrong diagnosis, you’ll waste time, money, and still have a damp house.

So before you throw thousands at injections, take a breath.
Look under the floorboards. Check the drains.
Because “rising damp” should be the last thing you consider—not the first.