BSF News

What’s been going on

This week we have progressed the steelwork to Section 3, which includes the larger classrooms to Food Tech, Engineering, Science and Textiles as well as humanities. We have also installed the pre-cast concrete stair cases to Section 1.

Photo 1 (gallery below) shows progress to Section 3.

Photo 2 shows installation of the pre-cast stair at the end of Section 1. As you can see the steel frame now sets out the sweeping curves that define the new College Building’s external appearance. Several of our operatives have remarked that the building looks like a work of art.

Photo 3 shows the curved steel used in the transition between Section 1 through the external dining area into Section 3 and there are certainly some similarities with a modern sculpture in the changes in geometry and unusual connections of multiple members. By using computer design, which is then fed directly into the computers that control the manufacturing of the steelwork, the architect’s design can be turned into steel on site in less than 6 weeks.

Photo 4 shows a view looking out to section 3 from the new main entrance area. The timbers that you can see around the base of the column contain the cement grout that is poured around the column to ensure that it bears evenly on the concrete foundation below it.

Once the steel has been erected and the line and level checked each section is offered for inspection. When a section has been accepted the bases are grouted. This ensures that the structure can not move when the deck slabs and stairs are constructed.

Photo 5 shows the construction of Section 3 from the Learning Support classroom in Section 1 looking across the canopy over the external dining area. This canopy will have a “Green Roof” i.e. natural planting. The roof wil use Sedum as the main species. This provides natural insulation to the unheated space below.

Below the raised floor slabs to Section 1, we have been completing the drainage that “pops up” within the slab to take toilets, sinks, rainwater pipes, etc. Once this is complete the ground above the drainage will be reinstated and levelled. A polyethelene damp proof membrane will be laid over the area and insulation placed around the building perimeter.

As you can see from photos 6 & 7 these drains are shallow, lying just below the concrete slab. The machinery used is small to work in the low headroom conditions below the first floor slab and as result the noise produced is less than that produced by the similar operations that our ground worker has been carrying out to the building foundations and main drainage.

In Section 2, the Dance and Drama halls, we have been placing the stone fill to the underside of floor slab level. This is the level at which the damp proof membrane will be laid prior to fixing the slab shutters and mesh.

There are only 6 “pop-up” drain connections to form in this area for rain water pipes, so the works here will progress more quickly than in Section 1.

I understand that some people have been asking why some of the columns in this area do not extend down to the foundations. These are posts to support doors and provide the glazing and masonry walls with additional support to resist wind loading. The bottom connection for these posts will be made to the floor slab after it is cast. This ensures that the increased tolerance (typically +/- 5mm) for finished walls can be accomodated. Typically the steel frame tolerance taking into acount fabrication and installation is +/- 20mm. The foundations to the steel frame are 450mm below the level of the finished floor.

The stone around the perimeter of the building has also been built up to provide a level platform for the roofing contractor to install safety nets and edge protection handrail using elevated working platforms. Once this protection is in place roofers will be able to safely start work laying the roofing sheets.

Over on the sports pitches you will probably have noticed that our contractor has returned and is currently in the process of turning the lower pitch into a beach! This is the next stage of improving the pitch drainage, sand slitting. Using a tractor mounted machine a series of slots approximately 200mm deep and 50mm wide are cut into the existing pitch, this is immeadiately filled with a specially graded sand. Once installed this provides a water path for ground water to the lateral drains across the pitch which we installed previously.

Once all the slits have been cut the surface of the pitch is then machine raked to ensure that all the slits are completely filled and well compacted. Any excess sand is also removed. The grass is then cultivated until an established Sports England specification pitch is available for use by the College next year. Sticking with the beach theme, the fertilizer that will be used to encourage growth is maufactured from seaweed!

The new temporary access to the Sports pitches has been adjusted and upgraded to reduce the step climb on the previous route, and provide better hard standing.

The new outfalls for the pitch drainage to the Butterworth Brook are being completed to Environment Agency standard details.

Coming soon

• Erection of Structural Steelwork

  These works will be complete before the last of the GCSE examinations.

• Upper floor slabs

  The decking to Section 3 will start after next week’s exams. This activity will be a repeat of that for Section 1 last month. All works including concrete to the decks will be completed in approximately 4 weeks.

• Ground floor slabs

  As previously ground floor slab construction will continue into the Summer Holidays. All slabs will be cast before your return in September.

• Envelope

  This consists of the various wall constructions to the new building as the diagram and elevations below and the roof. The roof will be made up of long sheets similar in size to the metal decking sheets we are currently using to line the raised floors. Each sheet consists of a metal liner with a layer of thermal insulation covered in a plastic waterproof membrane. By using this composite roof system, as soon as the sheets are laid we create a waterproof enclosure to the space below. The laps between the top membrane are then be heat welded to create a continuous roof. This roofing system is commonly used on Tesco stores. The construction of the envelope will be ongoing for the rest of this year. The initial work will be fitting safety nets beneath the roof steelwork, laying roof sheets & fixing an external stud wall system to Section 1. The windows will later be fixed into this wall and the outside fitted with insulation which is then finished with a coloured cement/acrylic render. The colour is in the render itself so if it should become chipped over time the colour is not lost as it would with a painted finish.

  The roofing operation will be similar to the metal decking works to date but quieter. The stud walling work will be quieter than the steel erection as no cranes are needed to distribute the metal studs. They will be lifted on to the slabs with a forklift and fitted from inside the building between slab edge and the beam above. Once this walling is completed around the building (by October) this wall will provide further screening to the existing college from the noise and activity continuing inside the new building.

Regards,
John England – Carillion Project Manager