External Rendering

[dtl]

Hello,

We live in a field stone house with rubble infill walls.
The majority of the external walls are harled with lime mortar.

The bottom two feet on one of exterior walls was not harled.
A couple of years ago we had this remaining section harled.
Unfortunately a cement render was used.
This has led to damp on the lower section of the interior wall.

We are going to have this cement harling removed.

My question is; what would be best when the cement based harling is removed:

a) leave the lower external section of the wall without rendering.
b) Render the lower section with a lime render.

Thanks

 

[middi]

Traditionally no render was ever applied at any levels on these buildings, cement render is definetely out of the question ( due to reasons that you have already found out), Just repoint in lime mortar and make sure that you have very free drainage around the perimeter of the building.

 

[Penners]

Did you have a particular reason for harling the plinth?

It's difficult to be unequivocal without knowing a great deal more about the house, but in general I believe that the plinth is best left "naked", as this offers the best possible route for damp to be lost to the ambient air.

 

[dtl]

We have no reason for re-harling the plinth if it is not necessary.

The french drains at the back of the wall in question were recently rennovated.

We will strip off the lower section of harling and tidy it to a straight line.

Thanks for the advice.