Cob: Re: Drainage

[Sarah Kopp]

If you have three whole stories built into the hillside, draining may be
very expensive - I believe you have to dig out the walls all the way to the
bottom and layer drainpipe - either the perforated plastic pipe or
perforated clay, layer that with large gravel, and of course water-proof the
walls before filling in.

Here in Safed, Israel, an ancient hill town, the old stone houses are also
built into the hillside and the cheapest, most accessible way of dealing
with the problem is to build a new wall inside the house on the hill side,
about 20-30 cms from the exterior wall.  Of course you lose floor space but
it does alleviate the seeping moisture problem, especially if you can have
the wall vented at the top to the outside.  If you also have rising damp,
you can dig up the floor where you put this interior wall and insert a
capillary break - heavy duty nylon sheeting (do you call it plastic?) and
scrap styrofoam seem to do fine - under the new wall and along the back
side.

Good luck.

Sarah
Tsfat, Israel

>I have recently bought a stone built house in the Pyrennees, (French side).
It's a four storey dwelling and
>the first three floors are built directly into the hillside. I'm looking
for information on constructing a suitable
>drainage system to help dry out this side of the house. I've got some
details on french and curtain drainsbut
>need some more stuff on the construction of berms and swales. The cob book
authored by Mark contains
>some information on this but I need more. Any ideas?
>
>Many thanks
>
>Roger Entwistle
>
>
>