Welcome to the Big Build Blog – 2009 edition!
Follow progress as we add three new homes and refit and refurbishing two other buildings that will play a key role for INSITE09 at BRE in June. Pictures are posted a week or so after being taken. Prefer a daily update - find me on Twitter
Enjoy the read, and remember to book your INSITE09 tickets to come along and see the completed buildings in June.
Words and pictures: Peter White at BRE. Photographs are copyright, and the comments here are my personal observations.
Update 21 April.This update introduces the other two new builds as part of The Big Build for INSITE09 – the Prince of Wales' Foundation for the Built Environment's Natural House, and the insulating concrete formwork-built Creo apartment block, and covers the peiod to the beginning of April. Learn more about these builds from the Big Buld area of this site. Later updates will continue to follow all three builds together in chronological order and also highlight work going on to reconfigure the former Rethinking School as a modern healthcare campus and look in on the competition-winning landscape design to be created at BRE. If you're new to this page, read the earlier posting below first. |
February 2009 - Prince's Foundation for the Built Environment's Natural house begins...   |
| Above: Roger Bullivant have provided the foundation systems for all three of our Big Build sites. Here we see, from left, initial site clearance for the Prince's Foundation's Natural House, the piling mat in place, and the first tubular steel piles being driven into the soft Hertfordshire clay. |
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| As with the Renewable House (see the first posting, below), the piles are driven down until a solid rock layer is reached. The tape shows this to be 11.6metres down. Concrete and rebar fills the tubes, heave protection is added and the concrete pile caps are fitted (centre shot) and right, once complete. |
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Jumping ahead a bit (the stages are very similar to those seen in the Renewable House), the Natural House has greater amounts of sub-floor insulation (seen above left). The final floor screed was poured on 31 March. |
March 2009 -The Creo building begins  |
| Above: On 5 March the largest piece ofof construction plant to be used so far during the Big Build rolled into the BRE site. The Bullivant Continuous Helical Displacement (CHD) piling system creates no arisings (ie, no waste material is brought to the surface). Instead the bullet-ended auger compresses material sideways, adding additional strength to the piles and allowing them to carry larger loads than auger-drilled piles of similar dimensions. |
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| Once fully set up, the CHD rig towered above BRE's large Structural Testing Hall (the concrete buildling in the background) which puts the top of the mast at over 20metres tall. |
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| The drilling head is seen here being fitted to the bottom of the hollow shaft, the machine is edged into position over the blue centre marks on the ground, and the hydraulic torque head (out of shot) drives the bit into the ground. Although there is a slight initial uplift of material at the surface, there is little disturbance to the surrounding area, and minimal noise too. |
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| These two shots shows the full rig in operation. The drill drives down to the full depth, and then concrete is pumped down the hollow centre to form the pile as the drill is withdrawn. The high view shows where the Creo building is in relation to the other buildings of the BRE Innovation Park. |
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left to right: withdrawing the drilling head, with concrete visible at the surface; lowering the reinforcing bar 'cage' into the pile; and carefully checking the final location and centres.
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| A week later (12 March) Housing Minister, Margaret Beckett visited the site (seen here above left with Creo Director Willem Kaldenbach showing the BASF Neopor ICF system). On site, the ends of the piles are excavated around and the steel exposed to allow the pile caps to be formed around the rebar... |
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| ...As in the other builds, heave protection is fitted beneath the pile cap, but this time plywood formwork is placed around the exposed pile ends and the caps are cast in situ. Further reinforcing steel is lowered in during the concrete placement. |
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| As this building is much larger, taller and heavier than the others, the foundation beams are a much larger profile and contain much more reinforcing bar. The drainage and service ducts will service 4 separate dwellings plus a retail unit at the ground floor.
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| Next installment... |