Diplomacy

Well I am pleased to report that common sense did prevail. The Structural Engineer asked for a 5 minute discussion of our differences before he would speak to the Contractor about our current problem. He aired his view that the work on the Detailed Plans had cost him more than the original estimate as a result of the changes and extra work that we had asked him to do. I countered with the opinion that the changes we had made were on the periphery of the project, not in the "difficult" areas where I would have expected the majority of the engineering effort would have been expended. They would not, therefore, account for all of the sizeable hike in fees. I also pointed out once again how very disappointed we were in the time taken to complete the job.

To breech the deadlock I proposed that I meet him in the middle of the difference between his final invoice and original estimate. This he agreed to, I wrote a cheque and we drew a line under that part of the work. Hopefully we can now start a new relationship with clearer channels of communication. As a result of this he has now handed over a sizable wadge of documentation that he had held back, mostly from the District Council concerning the Building Regulations approval.

We then went to talk to the Groundworks Contractor about the problem in hand. Earlier in the day I spoke briefly to the Buildings Inspector who succinctly stated that he wanted to see one of two things :

1. A statement from the Structural Engineer of the suitability of the design of the foundations for "filled ground". he had a brief discussion with one of the Structural Engineers sidekicks yesterday, and thinks it is unlikely we will get this statement.
2. A re-design that takes the ground conditions into account.

The Structural Engineer looked over the ground, consulted the plans, and re-checked some calculations. As I said in yesterdays blog, the calculated Ground Bearing Pressure is 30.6KNewton/m2, and the assumed Capacity of the ground is 100. This is fine for the rock/brash found on the Southern end of the dig, which he reckoned would be up in the 200-300 area. However, the filled ground in question will probably only manage 50 at the most. This is too small a margin for error.

He needs some time to think about the solution, but is aware that the contractor is now held up. Hopefully he will get back to us in a couple of days with a solution that will probably have already been approved by the Building Inspector.

The most likely outcome is that a pillar of concrete will be sunk down to rock in the North Western corner. This will support a beam under the northern wall which sits, at the other end, on the solid rock. The beam isn't really very different to the design already proposed. It will be thicker and with more steel in it. Of course, it will still sit on the ground in the same way as the original foundations. It just has additional strength in case the ground is unable to sustain the Ground Bearing Pressure of the walls.

After the Structural Engineer had gone I spoke to the contractor about this solution. It is standard practice. The other option of digging a full depth trench all the way along and filling with concrete would prove too expensive (lots of concrete) and produce too much spoil, even for our pit. He reckons this will probably get filled up anyway !

Not much could be done today. More concrete was poured into the underpins behind the blockwork, and they were gone by 09:20.

By the way, Jan opted not to get involved in this mornings discussions with the Structural Engineer. She could not trust herself to stay calm. Her sense of injustice is finely tuned !