After the quiet spell I described last month, it was all action when the bricklaying team of Nigel, Dave and labourer Nick turned up, with a cement mixer in tow, to start building the foundation walls ahead of a major site delivery.

Although full-width 300mm foundation blocks had been specified for this purpose, nationwide shortages meant we had to resort to traditional cavity construction, which would later need to be backfilled.

Mindful of the problems that rationing of scarce materials can cause on site, I wanted to ensure there wouldn’t be any problems with the next major item scheduled for delivery: the concrete floor beams.

I phoned the transport manager at the supplier to get an accurate date and time for delivery. When the order was originally placed I’d made it clear that our backwater lane location couldn’t accommodate the normal articulated lorries, so a smaller rigid truck with a HIAB crane would be needed.

Given how much notice I’d provided, I assumed this wouldn’t be a problem.

Delivery was confirmed for the following Thursday: “It should be later in the afternoon; you’re the one after Beaconsfield,” said the manager. This was pleasingly swift progress, with the beams manufactured and the order completed in just 12 working days, well within the originally estimated two to three weeks.

Beaconsfield is about an hour’s drive, so I figured we’d be offloading around mid-afternoon.

The Trenches Flood

trenches flood bailing out

The workers were forced to bail out the trenches
by hand after heavy rainfall

With the mini digger still on site it made sense to get the slim trenches for the underground rainwater pipework excavated. When you’re building an extension, the depth of the drainage system is largely determined by having to connect to what’s already there, and it turned out that our surface water pipes were significantly deeper than the foul drain runs.

In my opinion, it would be a good idea if underground rainwater pipework was a different colour from foul waste, but in practice both use tan-coloured plastic or terracotta.

Although pipework needs to be laid to a shallow fall of about 1:40, underground rainwater systems get an extra boost from water descending through downpipes, which exerts a downward force helping to propel it through the subterranean system. In total we needed four lengths of 6m-long 110mm plastic pipes plus an inspection chamber (a spare one salvaged from the old foul system was utilised).

That night torrential rain turned the site into a shallow swimming pool set amid a sea of mud. So the following morning work was held up while the brickies bailed out water with shovels. But the weather started to cheer up. Once Godfrey had completed the foul drain modifications and checked the falls, the oversite underfloor area could be levelled and covered with a weed suppressant fabric membrane secured with shingle and sand on top. Builders sometimes forget to place a bed of shingle under new pipework so we made sure this wasn’t omitted. 

With the lower walls now complete and dwarf sleeper walls in place to support the ground floor structure, work on site tailed off in anticipation of the delivery of concrete floor beams, which was scheduled for Thursday afternoon.

Delivery Problems

beam delivery hiab

The delivery driver, despite turning up too early, successfully delivered
the massive beams despite the tricky site access

The second building control visit wasn’t due until construction of the ground floor was underway, so the site was vacant once again. Pre-cast concrete floor beams are extraordinarily heavy things and can’t just be plonked down anywhere. The builders weren’t expected to arrive until after lunch with a powerful digger to help offload and manoeuvre them so they didn’t block site access. 

On any construction project there’s a familiar soundtrack, often punctuated by the routine beeping of trucks reversing, so I only faintly registered the arrival of a huge lorry at 8.15am. I assumed it was Buildbase delivering jumbo bags of cement and shingle, but as the truck came into view I could see it was loaded to the gunnels with dozens of giant pre-stressed concrete beams — about six hours earlier than scheduled!

It was far too large to make it up the drive and with no one to help, and the rear-mounted crane of limited reach, it looked as if the beams would end up being dumped on the street, or have to be sent back and redelivered a week or so later, wreaking havoc with our build programme.

The driver seemed unaware of the scheduled delivery time; this was his first drop of the day. The main beams were a hefty 4.3m long and weighed 150kg apiece (35kg per linear metre) and were packed in sets of five or six, with each bundle weighing around 750kg. Navigating large heavy loads at height takes considerable skill and he worked hard to make the best of an unfortunate situation, stacking them neatly six layers high.

I phoned the transport manager and pointed out that it might be an idea to communicate with the client if delivery times changed. But it was a timely reminder for me that promised delivery times need to be taken with a fairly large pinch of salt. 

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