Most of the floors at Balintore Castle have been rebuilt, but a few are still as they were when I bought the building. These are the problematic floors where the underlying beams are rotten but difficult to access, either for repair or replacement. There is always the danger, of course, that removal of a section or the whole of a rotten beam causes the whole floor to collapse.
One of the problematic floors is that in the "Women Servants' Bed Room". This is room directly above the great hall and the beams are so far above the floor of the great hall, that scaffolding would have to be erected underneath to access them. Every so often I have suggested to Gregor that the floor could be possibly repaired from above, but Gregor insisted that the scale of the work was so large that it could only be done from below and that plaster moldings would have to be knocked off the ceiling of the great hall to gain access.
Given that I am currently at the castle for a prolonged period, Gregor and I had time to look at the various problematic areas of the floor in situ. There is nothing like being there in person to understand what the problems are and to set the brain in motion as to how these can be solved. There were around 5 areas damaged by water ingress through the roof. Importantly, it looked like these could be fixed up one-by-one. Although extensive, the damage was localised, so we could patch repair rather than replacing whole beams. Even Gregor agreed. :-) This is where you have to think on your feet as the problems are not easy. And in fact, Gregor is superb at coming up with working solutions for problems which would defeat most people. It was really productive to talk things through as we batted the ball back and forwards to develop practical solutions, be it the order of doing things or the design of a new metal bracket to tie things together.
Gregor finally set to work on the floor. I was delighted as this room is key to reclaiming accommodation on the top level of the castle. This large central room would make a superb communal lounge/kitchen serving all the bedroom accommodation in the main body of the castle.
As Gregor stripped away, the extent of the dry rot revealed was alarming. How had the floor even supported our weight? We had crossed through this room all the time to move between the east and west sides of the building. However, we have experienced this phenomenon over and over again. Everywhere the dry rot damage has been revealed to be greater than we had envisaged, but because the castle is so over-engineered the structure still remains incredibly strong.
Particularly alarming were wooden beams which ran alongside an iron I-beam. These were more or less totally gone. The ends of other perpendicular beams which had slotted into these were now dangling in this air. And as these perpendicular beams supported floor joists, the mystery of why the floor had not collapsed was all the greater.
How could we reattach the perpendicular beam to the I-beam? After discussing a complex piece of custom metal work which hooked under the perpendicular beam and over the I-beam, my suggestion was that we simply extend the perpendicular beam with a short section of wood, but put strong metal bracing plates either side to give the joint a huge amount of strength.
In the images below you can see the "after" The perpendicular beam has been extended with custom metal plates and is now sitting on top of the metal I-beam. The old wooden side beam was on the same level and where it still exists (slightly to the right), it is just a hollow shell, with cubes of dry rot inside. The floor joist is in the bottom-left corner and resting on the perpendicular beam.
|custom metal plates to extend perpendicular beam so it again rests on I-beam|
If we zoom out one step, you can see the floor joist has itself been affected by dry rot and has had its end cut off! The end of this beam used to be supported by resting on a ring beam which ran along a wall. This ring beam had also succumbed totally to dry rot.
|floor joist renting on perpendicular beam - rotten end of joist has been chopped off|
If we zoom out yet anther step, you can see the floor (which we have sheet-ed temporarily in OSB (Oriented Strand Board) which somehow you can walk on!
|OSB floor resting on floor joists|
As Gregor stripped out more and more, I became increasing concerned that the whole structure would just give way, and finally persuaded him to put in some new support between stripping phases. However, Gregor was as good as his word and area-by-area the floor was patch repaired. Only one major hole caused by water ingress remains to be fixed. And there will still have to be a final pass where we replace the OSB with proper floorboards. The floor of the room still has a long way to go, but most importantly it has been saved and is now safe. A longstanding weight on my mind of "How can we possibly fix this?" has been lifted.