I'm investigating noise from next door in my 1960s semidetached bungalow.

From external measurements, from the edge of my window, to the edge of my
neighbour's, is 103cm. Internally, there's 27.5cm from the edge of the
window, to the wallpaper on the party wall.

Assuming the same arrangements next door, there seem to be 48cm of wall and
plaster between my house and next door. And from inside the loft, the wall
appears to be built of breeze blocks.

Can a breeze-block wall really be that thick? (It would appear to need 4
courses of blocks.) Or is there likely to be a gap (of some 20cm?)?

At the minute the wall might as well not be there...

What's the simplest DIY solution to largely drown out the sound of two dogs
barking next door? (Apart from wearing earplugs, moving house, or, my
preference at the moment, machine-gunning both dogs)

Thanks,

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bartc