Rendering

[wattis]

I have a detached 30's house 3 sides of which are surrounded by a wide-ish concrete path. This butts up to a concrete plinth surrounding the house and looks to be, apart from where some deterioration has occurred, virtually watertight.
The house is apparently on the site of an old watercress farm and, according to the neighbours is built on a raft.
The concrete plinth is badly deteriorated in places and the render is 4 brick courses higher than the DPC (which is the bottom course above the concrete path) which 1 believe isn't normal practice. However, the brick courses beneath the render are slightly proud of the exposed courses above.
I have removed the blown render and am left with a patching job. Some bricks very wet but seem to be drying out quickly.
I am fascinated to know why I have the proud brick courses but need to know whether I should simply patch render the dodgy areas (if I try to hack off all the render it will badly damage the bricks where the render is okay).

Should I use a waterproofer in the render ?

Should I seal the joint between the path and the plinth (it seems to me that if everything is done properly the path should prevent damp rising and my main problem is preventing lateral splashing ? )

Any advice very welcome as I don't like messing with a DPC I don't entirely understand

 

[dann09]

Perhaps, post pics of good areas and bad areas if thats possible?

Research on here and plastering forum - this is a well, and recently, covered subject.

 

[wattis]

Thanks for responding. New to site so didn't realise so much on here. Will attempt to post photos in next day or two. Trouble is there seems to be different ways of dealing with this - in short do you seal the render (and lock in the damp) or let the wall breathe ( and let it get wet but allow it to dry naturally).
Have removed damaged render. Where render has deteriorated bricks behind saturated and one or two falling apart, where render okay wall much dryer. Render quite thin and internal walls not suffering severe damp (walls are cavity so not bridged ?) - I don't want to repair render and actually create a problem that didn't exist before by using wrong product).
Where walls wet they dried out very very quickly and even when rained on look dry now