improving damp walls

[tractorman]

I have principally a 16th Century cruck frame building which over the years has had the frame either stone filled or the walls replaced with stone, however, my problem is an 18th Century stone walled added wing which is cut into sloping ground to the extent of being at a maximum 18" below the external ground level, Additional this wing and all of the North, East and South faces now have a profiled concrete render at ground level to act as a "gutter" for rain spill from the thatch. Not surprisingly I have a damp wall situation.

some internal faces of external walls have received a waterproof render up to 3 ft above floor level, but the wall above the render line is considerably damp

I am proposing to remove the "gutter" and dig a French drain around the perimeter of the house, hopefully some 9" below the internal floor level. There are suitable drains lower than the trench base to discharge into. I would also use a permeable membrane between the drain and soil to resist clogging the French drain fill.

Do you see any problems with this line of attack

 

[middi]

You definetely need to dissipate, get rid of, disperse quickly or drain away any surface water as far as you possibly can away from the base walls, if you do not do it the walls will try and do it for you by capillary action and getting themselves sturated in the process.

What you are proposing sounds good.

I am no too enthusiatic about your water proof rendered situation.

One step at the time may be a sound approach.

 

[andrew gayton]

you will still probably suffer from damp in the lower section of the walling unless you actually retain the soil away from the wall; assuming that this cannot be done, had you considerd a ventilated matchboarding/wainscotting section to the base of the walling in question? this will obviously be a sacrificial element but will afford a dry internal surface. Tried and tested.

 

[Lime]

I agree with the advice and opinion given so far.
A french drain does not allow drying of the lower wall and that is important too.

 

[tractorman]

many thanks gentlemen.

ventilated skirting are new to me, but I will give that some consideration where applicable.

 

[Penners]

Tractorman - if you do decide to go ahead with your french drain, just be careful that you don't dig down to the bottom of the foundations. On a house of this age, they probably won't be very deep.