I live down hill from my neighbour and the there is a retaining wall between our two properties that is about 6 foot high. It is brick built and 9" wide. It is about 25 foot long. There are four drainage/weep holes positioned along the wall approx. 2 foot from the bottom.
When it rains heavy some water comes out from the weep holes but also bleeds out though the bricks and pointing in between the bricks.
I had a builder round today to see about re-pointing the bricks but he advised tanking the wall and rendering it. He actually mentioned using bitumen for the waterproofing and then rendering. I can't dig out behind this wall to do anything as my neighbour has recently had a new patio laid.
My question is does waterproofing the external side of the wall sound like a good idea. I would obviously not block up the weep holes so water/moisture that builds up behind the wall could still escape here.
Hi markbrick, The problem with tanking the wall is that water will then be retained by the bricks, during a spell of freezing weather freeze/thaw action will occur and this may blow off the render coat. Probably better to redo the mortar joints and allow the wall to breathe. Regards S