So, after weeks when not much appeared to change, suddenly there are big, obvious developments.
The work on the retaining walls and paving has moved on substantially now, and it’s pretty much off the critical path. There is still (a lot) more to do, but the shape of the paving and steps all round the house is clear, and we are on track to complete the wall that will retain the bank to the right of the house. That will be a great relief, as it will mean that both Alf Blackman’s drive, and the sewer pipe beneath it, will be properly secure.
But today’s particular fun was the lifting into place of some of the big structural timbers for the roof.
Josh was out in his BYT again, a huge JCB forklift, with an enormous reach
Clearly serious stuff, as Josh had to turn his hat round!
The most impressive job was lifting the ridge beam for the roof above the master bedroom into place. This is a 420×140 glulam beam, that located in a pair of sockets at the gable and at the junction with the main roof
The fork lift lifted it about 10m above the ground, and 6 or 7m over, and dropped it directly into place. Well, it was 8mm out, but I suppose that’s OK in the circumstances. Jamie seemed particularly impressed!
The remainder of the work was lifting some more huge timbers into place for the main roof
Tricky, mainly because access is a bit limited. But the forklift was truly impressive
April was an extremely frustrating month. After the rapid progress we made at the end of March, things pretty much came to a halt at Easter. Josh and his team finished the work they could do on the timber frame without scaffolding in place. The scaffolding, in turn, depended on completing the retaining wall to support paving across the front of the house. Then the weather intervened again.
The news in April was full of declarations of drought, hosepipe bans and dire predictions of standpipes in the streets. “Worst drought since 1976!”. Then the rain started. And it rained. And it rained. Then it rained some more. On the radio, someone said that it had been “Droughting heavily in Cardiff”. Whilst the site was not as badly flooded as in January, Darren, one of the groundworkers, lost his bet about the depth of the water in the Void, when it overflowed the top of his wellies. Then it rained some more. So progress on the retaining walls was painfully slow.
Bore Holes
Drilling Rig
At the same time, the bore-hole drillers finally arrived, after a few false starts, to drill our 210m of borehole for the ground-source heat pump. There were supposed to be three holes, each 70m deep. Our information was that the house sits on Bude Formation sandstone; we had expected, therefore, that the boreholes would be fairly straightforward. In the event, things were not quite so simple.
The drillers set about the first hole, and quickly hit the water table at 7m down. That meant a cascade of water out of the hole, propelled by the compressed air used to drive the drill hammer. So another river down the site – fortunately, flowing away down into the River Deer. Then, rather than the uniform sandstone we had expected, they found the rock fractured and containing loads of hard inclusions, which made the drilling difficult. Eventually, they managed to get that hole down to 53m – some way short of the planned 70m, but usable nonetheless. The next day, a second hole. Most of the same problems, but eventually, the hole went to 79m; better we thought. But then the next problem. The drillers had had to insert a temporary steel casing in the top 20m or so of the hole, to prevent it collapsing. Normally, they would withdraw the casing with the drilling rig. When I arrived on site, the drillers were sitting in their Land Rover, wondering how to extract the stuck casing. Shades of “Need a bigger hammer!”. The legs of the drilling rig were bent, the casing stuck firm. Phone calls to the boss, and general despondency.
A day or two later, we returned to see a pair of HUGE hydraulic jacks around the top of the hole. They could evidently exert 30Tonnes force, and managed to extract the rogue casing. So, we now had 132m of bore hole. All we needed was another 77m, and all would be well.
We went to site on the day they had started drilling the third hole. The rain was coming down in torrents, the wind blowing. A perfect spring day in Devon, then. “How’s it going then?”. “Not well. Down to 30m, and hitting real problems”. We stood inside the house, out of the pouring rain, and watched the driller, standing in the rain, with a torrent of water coming up out of the hole, and the drill turning, catching, having to be withdrawn and tried again. This was not going to plan at all, and we wondered what Plan B could be, particularly when the poor chap threw his hands up in resignation and retreated to his Land Rover.
The conversation before we left amounted to “Not going well, do the best you can, see how things go”. We didn’t expect much, to be honest. When we returned the next day though, the news was good. The drillers had stopped for their lunch break, then gone back to work on the hole. They had struggled for 15 minutes more, then the drill had found easier rock. The hole was now down to 79m, and we were OK, provided the pipe loop would go down smoothly. It evidently did, and we now have three pipe loops sticking out of the tops of the boreholes awaiting terminations.
More Groundworks
The critical path for the build was now the completion of the retaining structure to support the path in front of the house. This is needed to support scaffolding to complete the upper floors, and to support the porch structure on the house. The speed of progress here has been frustratingly slow, and the work is still not complete. The weather has not helped, certainly, but there are some other factors too.
In the interests of getting things moving, then, Sean (project manager) suggested that we erect the scaffolding around the rest of the house. Josh is happy to work off that to put the roof on the frame – about 2 weeks’ work – which has to be enough to get the paving in place.
So, yesterday (Friday) the scaffolders arrived…
And so did Josh, Rick and Jamie
And Brian, Jerry, Malcolm and Darren
More men on site than I’ve ever seen before!
By the end of the day, the scaffold was complete.
Meantime, Josh was using one of the Big Yellow Toys to lift the floor panels on to the top of the frame…
Josh will now carry on with the top floor. This should be complete in about 10 days, when we can get the roof felted and battened. Weatherproof.
The two weeks or so since the last post have seen a lot more obvious progress. Both the retaining wall that keeps the hill from falling on the house, and the timber frame have grown a lot, thanks partly to some exceptionally good weather.
The Timber Frame
The last post here showed the bottom floor of the frame ready to receive the joists for the next floor. Pretty quickly, the joists were in – thanks to some terrifying walking across the open joists by Josh and Rick – then the floor deck went down, and we had a sort of outsize garden shed.
Then, so as to avoid the need to work around scaffolding (and to get them out of storage), Sean installed the bi-fold doors in the living room and dining room.
We now have most of the middle floor of the house in place. There was one small hiccup, that Sean dealt with. Josh had been proposing to build a walkway across the ravine separating the bottom floor of the house from the bank at the top of the site. In the bottom of the ravine was the concrete footing for the retaining wall, complete with projecting (by about a metre) steel reinforcing bars that would connect the wall to its foundation. I had nightmares about one of the framers falling and impaling himself on the iron maiden below! The problem was resolved, by Josh and his team unloading the Potton lorry on the driveway (that we don’t own) at the bottom of the site, then carrying them to the house by hand. Laborious, but at least not deadly.
So, a few days later,
Josh and his team were just finishing off the external panels on the first floor
Quote: “If it won’t fit, you’re just not using a big enough hammer”
Once the exterior panels were up, we could go up and look around. Again, surprisingly, just like the design!
The Retaining Wall
Meanwhile, more has been going on with the retaining wall construction. The next step was to pour concrete in to the foundation slab. This meant a similar concrete pumping exercise to that for the house footings.
Then a skin of blockwork was laid outside the reinforcing bars..
Last step so far is to lay a few courses of the second, inner skin, and fill the gap with concrete. This has to be done 3 or 4 courses at a time because of the pressure exerted by the wet concrete.
When we left site on Tuesday afternoon, there was a floor slab and a pile (or several piles) of timber scattered around the site.
48 hours later, when we returned on Thursday afternoon, we had most of the bottom floor of the house…
Josh and his team had made great progress over the 2 days, assembling and erecting the 2 portal frames that will support the bifold doors on the living room and dining room, putting down the sole plates, erecting the panels for the outer walls and then putting in the internal walls.
For the first time, we can actually see the room layout. As Paulette commented “It’s just like we designed it!”. And we can now see the view across the river framed, as it will be, in the living- and dining-room windows.
Meanwhile, work on the foundations continues, in a sort of 2-steps-forward-1-step-back way. The groundworkers are now putting the reinforcing steel (back) into the excavation for the footing of the retaining wall.
Should be finished with this stage on Monday, inspection on Tuesday, concrete later in the week.
Josh & Co will be there on the frame next week, and maybe a little longer.
This morning saw the delivery by Potton of the first package of our timber frame. This comprises (mainly) the parts for the bottom floor of the house, which will sit directly on the floor slab. The plan is to build this, then for the groundworkers to return to build the retaining wall and the outer skin of the house adjacent to it, allowing the concrete path to be laid in front of the house. This will permit the scaffolding to be erected to allow the rest of the frame to be built and the roof constructed. So, today was momentous, in that it marks the beginning of being ‘out of the ground’.
Pretty exciting in its own right, too.
We arrived at the site shortly after 9 this morning, to find the road crammed with Potton lorries (well, there were two, at least). The construction team – Josh, Rick and Jamie – were expecting the crane for 10:00. It finally arrived, reversing down the road at about 10:30
A bit bigger than even the construction team expected! A while to set up, jacking the crane on to its levelling legs, and a bit of concern about the sewer across the top of the site,
then one of the Potton lorries reversed down to beside the crane,
From further up the road
and all was ready to start unloading. The plan was to put much of the kit in the centre of the slab. Josh and his team managed to get the main panel packs there,
but there was not enough room for everything, so some of the materials were dotted around the sides. Some of it looked pretty precarious, particularly this (very heavy) pack of plywood floor panels
But by 12:30, both lorries were unloaded and had left for their return journey to St Neots.
A few meetings on site, with Project Manager Sean, yesterday. The first with Richard from Source Energy, the heat pump supplier. This was to line up the drilling of the three boreholes to feed our heating system. The drilling company will be on site on Monday and Tuesday, to drill three 70m deep holes, and to lay a pipe loop into each. These will collect heat from the ground, which will be used to heat the house.
The next meeting was with Josh, from Timber Constructions, the company who will erect our timber frame. The plan is for the bottom floor to be delivered on Tuesday, and for them to erect it next week, then put on the floor joists and deck for the first floor. The Potton lorry with the panels is scheduled for 10:00 on Tuesday, along with a (substantial) crane to lift them down on to the slab.
Also on Monday, we have the inspection of the foundations for the retaining wall. The excavations are complete for this, and the groundworkers are currently putting in the steel reinforcing mesh and bars for the slab and wall. Subject to satisfactory inspection, this should mean more concrete some time in the week.
Now that we have a floor slab in place, the next phase of the groundworks has started. This is the construction of the retaining wall above the house, that prevents the hillside joining us in the living room. First part of this is to dig out some more spoil, to create the foundations for the wall.
This entails digging down about 600mm below the current level, to allow for a 250mm thick reinforced concrete slab. The main difficulty is access, as shown here. Jerry can only get the small digger in, and is limited on how much spoil he can move to the level above – plan is to move the big digger up to the top of the site, and fill its bucket fron the small one. We shall see!
What’s remarkable is that, for the first time, really, we can see how big the house will be, and start to see how it fits into the site. Standing on the floor slab makes it obvious just how well tucked away the house will be.
Also, now that Malcolm has started spreading the Spoil Himalaya across the bottom of the site, we can start to see the extent and lay of the garden, and confirm the way that it leads into the country beyond.
We’re now told that the first part of the timber frame will be delivered on March 12. That will just be the bottom floor panels and floor joists for the middle floor. Once that’s up, the groundworkers can build the blockwork wall nex to the hill, and lay the path outside the front of the house, so that the scaffolders can do their stuff. All seems, suddenly, very fast indeed. We carry on anxiously looking at the weather forecast, and hoping for dry weather.
The weather over the couple of weeks following my last post, when the concrete was poured, continued to be dire. While the east of England has had the driest winter for many years, Devon seems to have been deluged. Serious thoughts of building an ark, rather than a house! Brian, the groundworker, said that the weather had turned ‘..a difficult site into a near-impossible one…’. The ground conditions were terrible, slippery mud that sucked your boots off if you stood still for more than a few seconds. The tracked excavator was stuck in the mud, and the standing joke was that we could put some hanging baskets on it and use it as a garden ornament.
Fortunately, the weather over the last couple of weeks has been drier, and work on site has been possible. By the end of January, we could see the blockwork walls that would complete the foundations…
But then work seemed to pause for a while, as we had more rain. But yesterday, we went to the site and were stunned to see the floor slab in place…
The beams had been craned directly into position – just as well, as manual handling would be impossible for the 5m long, 200mm deep reinforced concrete beams – and most of the whold blocks were in place. Most of the projecting pipes are the drainage tails for soil and vent pipes, though the two close together in the foreground are ducts for the header pipes to the ground-source heat pump from the bore holes.
The guys were working on filling in the remaining gaps with cut blocks..
Yes, at last, after delay, storm, tempest and flood, the concrete went into the footings today. An immense sigh of relief, and, at last, the feeling that we are actually building something.
Last week’s floods had subsided within a couple of days, but the ground round the excavations remains very muddy – stand still too long and you lose your boots.
This shows the trenches at aboout 9:00 this morning. The NHBC inspector had been to site yesterday, and approved the trenches, subject to my confirmation that they were still clear, and that the surplus water was removed.
The groundworkers set to with buckets and shovels, and took out most of the water, leaving a sort of muddy slurry in the base of the trenches. Then, bang on time at 9:30, the concrete pump arrived.
Followed shortly by the first concrete mixer, with 6m3 of concrete. The pump has a long, extending nostril, and pumps concrete fed into a hopper at the back of the lorry.
Filling up the trenches really didn’t take long.
Here’s the result, before the arrival of the third and final lorry-load of concrete.
So now, 20m3 of concrete in the ground, we really start building. Blockwork up to damp-proof course level next.
Monday night and Tuesday morning saw the UK swept by fierce winds and heavy rain. Looking out the window on Tuesday morning, watching the rain going past horizontally, it was inconceivable that Brian the groundworker would be able to do anything today. When the NHBC inspector rang to confirm his visit, my inclination was t0 cancel on the spot. But a few phone calls later, we established that Brian’s men were on site and expecting the inspector that afternoon, with the intention of pouring the foundation concrete on Wednesday – the concrete pump was booked.
The drive up to Holsworthy was interesting – water pouring out of the fields, huge puddles everywhere. The river at Ashmills had burst its banks, and the rain was still coming down in buckets. When we got to the plot, this is what we saw…
The groundworkers were wading around in the trenches, removing the loose spoil and trying to remove some of the water
Water was flowing into the foundations, percolating through the ground from the hill above, and filling the trenches as fast as they could bail it out. No prospect, then, of the NHBC signing off the foundations as ready for concrete! So we cancelled the concrete pump, and agreed that we would try again on Friday, as the weather forecast for the next few days was drier.
Meantime, how to help the site drain better. One of the groundworkers suggested punching a gap in the bank at the bottom of the plot…
5 minutes with the JCB later, we had a drain, and the satisfaction of seeing the water running away.
