Now with the back wall finished, and being in the “cement mood”, I decided it was time to restore the big wall that divides the Workshop on the street-side and our B&B apartment on the other side. This wall is the biggest remaining part of the old ruin, almost 7 meters high and is still standing after 200 years, although it’s just stacked with stones and some clay.
It will be there forever, if… there is no rainwater splashing on the top. As soon as these kind of walls stand alone without being protected by a roof they get vulnerable. The biggest challenge is to get the buildings on both sides connected with a movable, but rain tight, fixture. Movable because this old wall will set it self every time there is a big storm or earthquake. Yes the last couple of hundred years there were minor earthquakes in Portugal. And in 1755 the Great Lisbon Earthquake (occurred on Saturday the 1st November) combined with subsequent fires and a tsunami, almost totally destroyed Lisbon and adjoining areas. Seismologists today estimate the Lisbon earthquake had a magnitude in the range 8.5–9.0 on the moment magnitude scale, and the death toll in the area was between 50,000 and 100,000 people, making it one of the deadliest earthquakes in history. But if you look at all the historic buildings like castles and aqueducts…they still stand tall. These wall have the ability to move with shocks and to bent under heavy pressure. Our ruin did well in the last earthshaking of 1948. The downside of it is, these walls are hard to combine with rigid materials.
My job was to make shure the top of the wall was able to stand all the heavy rainfall we get in the wintermonths. Now I did it with a layer of steel supported concrete, wich is only connected with some steel plugs every half meter into the wall. So the wall can expand and shrinck underneatn the slap of concrete.
On top of that there is a thicklayer of bitumen (it took 8 coats) and the gabs between the wall and the roof of the appartment on the back is filled with a special kind of bitumen / silicon kit (that came in 1 meter long bars of 5×5 cm), by melting it in with a blowtorch.
All the gaps were filled with a mixture of cement, the old clay and some water resistend fluent. As you can immagen there are no tools for that, so it took 8 sets of gloves and some sore fingers to get the job done.
The good thing of al this, it got me over my fears of hights, being days on top of that wall.
Next time: Getting a roof on the workshop
-- Não só Serradura, Tomar, Portugal http://notjustsawdust.blogspot.pt/