Holdfast Training Services Trial Blog

I started this as a reply to Damo’s blog but it became a bit epic so I thought I’d make it a stand-alone blog.  So it you haven’t read his; read that first, or just instead, it’s better than mine anyway!

The client has contracted BLP as its insurers for the project.  They visit at certain times to inspect the things most likely to cause a claim.  At this early point in the build it’s waterproofing.  McAlpine are still picking up the pieces from a job finished last year where the basement is now leaking.  They have spent over £1 million injecting grout into the walls and water is still getting in.  Later on the insurers will care about the façade, and the roofing, anything that could let water in.  But right now it’s all about the waterproofing under the concrete.

It’s not that BLP don’t care if the building falls down, it’s just that thanks to all the other checks that happen, and likely hood of such an event, they’re focussed on the stuff that might cost them money in the long run.  They just assume the actual structure will be alright.

They have paid particular attention to manholes.  And quite rightly, as the first 3 we built we massively messed up!

The first isn’t waterproofed at all.  The second is, but a movement joint was incorrectly installed and now the membrane is torn, and the third one used waterproof concrete that it turns out is less than waterproof.  All of these will require remedial waterproofing works which we are waiting for the waterproofing designer to come up with before the architect approves it before we can instruct the install.

To add further complication these three manholes were installed by our previous drainage sub-contractor who walked off the job some time ago after they hadn’t been paid.  When our new drainage sub-contractor surveyed the manholes they discovered that at best the invert of the inlet was level with that of the outlet, and in one particular case the inlet invert was 40mm higher that the outlet, see picture below.

The worst manhole ever!

The curved 100mm dia (4” for Brad and Henry) pipe is the inlet.  The straight 150mm dia (6”) straight pipe is the outlet.  The reason the 4” is curved is because it enters the manhole at such an awkward angle that the benching would be a nightmare so a curved bit was added.  By removing the curve (requiring local breaking out around the joint half embedded in the wall) we managed to achieve a 15mm drop (whoop whoop) and we’re hoping that with some artistic benching we can make it work.  Luckily that inlet comes from a floor gully, so at least we don’t have to worry about trying to get a poo round the corner!

I’ll keep you posted…

In other news I have managed to talk two blokes from my site into the Care Construction Challenge, a 26.2 mile cycle, run and kayak race in the peak district.  We all have to do all the legs and I have promised that if we raise our target amount that we’ll complete it in dresses.  So please sponsor us at https://www.justgiving.com/LillieSavages/.

Thank you!