A Stitch In Time
Stripping back the loose plaster from the bedroom walls and ceiling revealed no serious structural problems, thank goodness. It looks a lot worse than it is. In places we can even now see the underside of the thatch. A thatcher doesn’t usually take off all the old straw when he re-thatches so this bottom layer could be quite old. Mice often nest in thatch, burrowing tunnels through the straw. No peeping furry faces thus far but we’re not taking chances. The bedroom door is staying firmly shut!
The next stage will be to replace the missing laths. Any that had deteriorated have already been removed. Nailed to the roof timbers, the laths cover the straw and provide a key for the plaster used to construct the ceiling.
The cottage walls are constructed from rubble and cob (clay soil, sand, water and straw). Cob is a porous material and tends to change its consistency across the seasons. In summer it dries out, in winter it absorbs more moisture. This is why it is so important to ensure that the plasters and paints used to cover it enable the wall to ‘breathe’ by allowing for evaporation. Otherwise the moisture is trapped and the cob starts to rot.
It’s perfectly normal for the structure of this type of building to move a bit over the years. Above you can see where the cob has shrunk away from the stone used around the doorway.
For extra reinforcement the builders have ‘stitched’ the gap before filling it with lime mortar.
At intervals up the wall they’ve inserted a HeliBar, a helical shaped steel rod, bonded to the stone with resin. The other end is inserted deep into the cob, driven into place with a specialised drill. We watched as the first one went in. Only the one mind because the noise and the dust were truly something. There were occasional furtive glances out of the window to make sure the rod hadn’t emerged right through the other side but, no, job’s a good-un.
Good to go for another 400 years?