How to make a new doorway

The major building work at La Basse Cour at present is the construction of the new doorway in the south wall.

Opinion is divided about the best way to put a new opening into a stone wall. I've read in a book that it's as simple as making an arched hole in the stone 2x as wide and 1.5x as high and then building back in - no acroprops, no supports are necessary as the stone wall will support itself for the time required. Adam doesn't agree with this approach and prefers to use lots of supports and props - a fortunate approach as it turned out.

The new doorway takes the place of a small window and Adam started by removing enough stones above the window to push through two big wooden supports:

The original window

The first wooden support is installed

Then the stones are progressively removed until the doorway starts to take shape:

The walls at La Basse Cour are 75cm thick and a mixture of small and very large stones held together by clay

Adam constructed the doorframe using a mixture of old stones from the original window, stones that were recovered from the site and re-dressed and a custom cut new lintel stone. Even Adam's old stone friends from the original lucarne that was taken down, Frank and Henry, were found a place. (I'm not sure if, when the stonemason starts naming individual stones, that's a good sign or not ....)

The vertical doorway stones are installed

When the doorway is built to height the next stage is to install the stone lintel, Adam had carved this to match the existing doorway stone:

The lintel weighs about 250kg, the top of the doorway is 2.13metres high - that's a lot of stone to lift! We took it up using a winch hung of a scaffold bar and, with the winch taking the load at the top, moved it onto the new pad positions at the top of the stones:

The final stage of preparing the new opening was to remove some stones from the top of the archway to open up enough space to move the lintel in.

"Tim, you ought to have a look at this ...."  -  Oh dear, another "Houston, we've had a problem" moment.

Adam had found a big gap behind the beam where it was bedded into the stone wall. Birds and mice had also found the hole and so it was full of old nests and rubbish. The result of this was that the weight of the half the beam, all the stone above it, the roof A frame and the roof above it was bearing down on a small padstone on the internal wall underneath the end of the beam. Some signs of the strain this stone was under were visible on the inside in a crack running down the wall. It's a bit of a mystery as to what happened here as this isn't built to the standard of the rest of the building - "someone's bodged this up" was Adam's opinion. The beam is one of two very regular ones next to each other and I have wondered previously whether these are replacements. The good news was that it enabled us to closely inspect the end of the beam which, apart from the usual insect attention at the ends, seems to be in good condition. Adam had already jacked the beam up on an acroprop and so he was able to build in under and around the free beam, when the acroprop comes out the weight on the beam should transfer down via the new stonework into the existing wall. We've now seen the ends of four of the five beams at close quarters and, as a precaution, we will open up the wall around the fifth one at some point - just to make sure we don't have any other "Houstons ......".