Listed buildings need TLC, this one more than most!

Recently we have been dealing with another Listed project which has just got to site. It looked ok in the main until we started to look a bit deeper. We had some cracks running up the edge of the building, along what we thought might be the line between the brick and bungaroosh, and knew historically the building had moved.

Initial opening showed that the main spine wall in the property had dropped. More opening up revealed that it was not supported at basement level on anything more than a floor timber, and that was above a door head, and that was above a gas pipe…all holding up 3 floors above and 3 flights of stairs!

How do we know it was historic? Well the UPVC windows (that were installed without Listed building consent) are in the original timber frames, and these are nowhere near square. See left to right at the bottom of the window frame below!

We knew that the roof had issues but it had 2 pitches and one loft was not accessible. The roof slates had been covered with asphalt and bitumen so we were aware this needed work. We also knew that the valley between the roofs was leaking – this turned out to be in line with the spine wall drop, where water was now pooling as the problem was never addressed. The leak had taken its toll on the wall plate and structural stud below, so all the rotten timber needs cutting out.

All the rafters have rotted at the ends and nails rusted away; probably due to a mixture of age and condensation from the asphalt over the original slate roof stopping it breathing. As a short term measure, battens have been added to keep things in place! The ridge has gone in line with the spine drop. So…lots to be added in to make it safe and usable.

Under the roof and the rear of the building things get worse. Most of the lime mortar has been washed out in the top floor by years of neglect, being open to the elements and ensuites venting into the chimneys.

Bungaroosh panels of the rear walls have no toothing into the brickwork and we can see a visible gap to the wall (partly where the external crack is and more signs that the building dropped).

To give you an idea of what the lime is like check out this video below:

Update 11/06/19

Now we have opened up the building even more, we have found that the floor timbers are all different and will not take the new imposed loads under current building regulations. The structural studs are holding up ok, but the heads of the walls have come out of their pockets in the wall, again showing that the spine of the building has dropped.

How about this for the end of usable life? All the flat roofs are well beyond economic repair and have leaked water into the timber frame structure. These will be renewed and rebuilt with something more in keeping with the historic nature of the building (not asphalt and glass reinforced plastic (GRP)!).

Update 13/06/19

The first floor plant room, which was an extension in the 1920s, is also continuing to be a can of worms. Years of notching and additional services and leaking services meant that if a joist was not rotten, it had been notched way outside its original design strength. And…you guessed it, the joists are notched into a timber that is taking the load of the floor above, and it’s rotten…!

The list of defects is pretty astounding. We are now looking at bolting the chimneys back together, we have found the basement chimney has had another layer of brick put on the front of it and in the hearth (which is all coming away), and various walls are coming away from the bungaroosh.