ᐅ Renovation of the vertical damp-proof course – masonry junction

Hello everyone,

We have purchased a house built in 2002. According to the floor plan and construction description, we have 36 cm (14 inches) Poroton external walls without an external thermal insulation composite system (ETICS) on a waterproof concrete slab with a frost protection edge. Around the house, there is a gravel splash guard.

After living in the house for about 8 weeks, we have noticed some signs of moisture on and inside the masonry in the base area:

• Previously minor moisture damage in a room at the outer corner.
• Hollow (outer corner) tiles on the wall in the guest bathroom.
• A large number of insects in the splash guard area (woodlice, silverfish, spiders, other crawling insects).
• A few silverfish inside the house despite relatively low humidity (< 45%) at 20 - 23 degrees Celsius (68 - 73°F) and regular cleaning.
• The base plaster and paint are hollow or flaking off in spots.

Today I took the time to remove the gravel and take a look. Honestly, I was a bit shocked by the condition.

• Pictures 1 & 2 show the base area next to the patio door (cut on the floor plan).
• Pictures 3-6 show the continuous area up to the marked spot.
• Picture 7 is a section of the floor plan with the marking.

I cannot tell if there is any vertical damp-proof course at all — maybe only mineral-based. In the area I marked on the floor plan, the masonry even seems to partly sit on top of the concrete slab — what — and several layers of plaster(?) were applied there.

But overall, it does not look like it meets TÜV quality standards… and this is only about 4 meters (13 feet) out of more than 30 meters (98 feet). The previous owner was obviously industrious and painted the base right up to just below the top edge of the gravel bed. We knew about the slight hairline cracks above the gravel bed top edge, but they seemed normal for a house of this age.

My question is — how urgently do I need to address this? How do you assess the situation based on the pictures? What do you think was done here? At the moment, we are busy renovating, and due to other projects, we probably won’t have time for this before next year.

Huge thanks in advance :-)
Best regards