Damp around bay window

[curium]

We bought a house built in 1934. Been in since March. There's some evidence of historic damp around the bay window in the living room. The front path is block paving right up to the property despite being on a slope that would cause water to run towards the house.

Easy remedial work I thought. Took up the block work around the bay window to find a 75mm slab of concrete!

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I'm thinking to hire a breaker and remove this but just wondered if there is some archaic reason for laying a 75mm slab of concrete around a bay window?

The damp proof course is barely 50mm above this concrete slab.

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My intended course of action is to break up all this concrete, remove soil to expose 150mm of brick below the dpc and then back fill the area with 20mm gravel. A neighbour has suggested applying blackjack to the brickwork once it's had sufficient time to dry out.

Could someone with knowledge of the construction of houses of this age give an opinion on this course of action?

Cheers

 

[stuart45]

Have you got solid or cavity walls?
Break up the concrete as you said.
Don't stick any Blackjack on the walls.

 

[curium]

Solid walls.

Any specific reasons you recommend against the use of blackjack.

 

[stuart45]

Solid walls.

Any specific reasons you recommend against the use of blackjack.

Brickwork needs to breathe(allow moisture in and out) Blackjack traps moisture into the walls.

 

[curium]

Another question:

I tried attacking this concrete with my SDS drill and chisel bit but it was slow going.

Thinking of hiring something like the Hilti medium duty breaker. Anyone with experience able to comment on the suitability for the task?

Cheers

 

[stuart45]

When you hire a breaker look for the J number which is the impact energy. That Hilti one delivers 11.5J which is not much more than my Titan SDS of 10J.
It's OK for light brickwork, but for hard concrete I would look for something with 30J or more. This cheap one delivers 50.
Mac Allister MSBR1700-A 16.2kg Hex Shank Electric Breaker 230V | Breakers & Demolition | Screwfix.com

 

[^woody^]

Your problem appears to be water running down the render and into the wall above the DPC.

 

[curium]

Your problem appears to be water running down the render and into the wall above the DPC.

Hi Woody,

Could you elaborate on why you think that? In your opinion is it not necessary to expose the bricks below the DPC by removing the concrete?

Thanks