Kensington gardens, April 2010.
The basement below this property was suffering from an ingress of water.
The first part of the solution was to re-route the outlets for surface run off to one point on the east side of the building. This reduced the amount of water flowing over the top of the basement area.
The second step was to rake out and re-point the block pavers above the basement area to reduce any water ingress.
Finally it may be necessary to Vandex internally. This however will only be carried as a last resort if the current measures prove ineffective.