Holdfast Training Services Trial Blog

With a month to go left on site I’m conducting testing of drainage, finishing off the blockwork and still arguing over builderswork.

For the phase 1s: Manhole testing is something you will likely come across and dependant on the designer will either be completed in accordance with BS EN 1610 or (as in our case) a more stringent standard defined in the designer’s specification.  In this case that is imposed by the designer due to the local authority’s own more stringent standards.

Effectively we fill the manhole with water, leave it for an hour to settle (for water to be absorbed into the concrete and air bubbles to escape), top it up to the original level then start the timer.  After 30 minutes we measure the drop.  If it’s less than 25mm it passes, more and it fails.  Failure results in issuing an NCR (Non-Conformance Report) and tell in the sub-contractor to fix it.  Four of ours have failed, mostly due to leaks where the pipes are fed through the pre-cast concrete rings that form the side of the manhole.  The sub-contractor is planning on re-sealing the inside using a cement based sealant that is applied to the inside by a hand trowel.

As the blockwork nears completion the M&E (that’s “mechanical and electrical” in the civvy world not “mines and explosives”) contractor has decided this is great time to alter his builderswork drawings that show where they need holes to pass their services through.

The issue with moving the builderswork is not just that the hole needs to move, but the whole fabric of the wall.  Where we have a double skin wall that includes all the insulation and waterproofing, and in some cases a windpost.

All the blockwork I look after is in the basement.  So why does it need windposts I hear you say?!  It’s because in the temporary state the building isn’t sealed and therefore wind can get in and apply a horizontal load to the face of the blockwork.  In the double skin locations the windposts and located in the internal skins (so they are hidden by finishes) with a movement joint located in the same place on the outer skin.

For those of you who are overseas: You might well be in sunny Australia or gun mad America, but I went to the Rugby World Cup opening ceremony and England vs Fiji, so in my books – I win!

For those phase 1s who are reading this while on exercise Steel: Stop it!  Watch Scotland vs Japan instead!