Firswood School Sensory Pool | Bolton



Installation of aggregate in a difficiult to reach area

Bolton’s Firwood School is highly regarded nationally for providing first class education and care for secondary age children with severe or profound learning difficulties. Firwood is now co-located with the new St. Catherine’s Academy and within the major construction work undertaken was the installation of a sensory pool to provide many valuable elements for youngsters who need very special care in all aspects of their lives.

The 25m x 20m sensory pool enables pupils to enjoy exercise in an entertaining yet controlled and safe environment which is a key part to their learning process. Lighting and sound are combined within the pool makeup and the children are able to activate floating switches that change the light patterns to provide individual areas of comfort and sensory pleasure. The pool design by Barr & Wray, Glasgow, was constructed by installing a stainless steel wall system within a concrete pit. A significant amount of intricate and sensitive pipework is required to connect the pump and filtration plant area which passes through the area under the walkway surrounding the pool, this void was filled with 110m³ of Leca® Lightweight Expanded Clay Aggregate before installing the finished tiled surface.

Mike Fallon, project manager for Kier Northern, Liverpool, who supervised the construction from commencement through to delivery, was concerned that the back filling process was going to be long and difficult as the pool area was effectively land locked within the campus buildings, with the nearest external access being 40 metres away.

“The design required minimal weight loadings adjacent to the pool side structure and over the pipework and whatever we selected from the traditional materials was going to have to be carried into position by hand.

I looked at using a conveyor system but that was expensive and unreliable. The pool company suggested Leca® Lightweight Expanded Clay Aggregate as the best material for the job and this can be supplied in bulk and because it is so light and friable it can be blown through tubes by compressed air,” reports Mike.

A totally natural product, Leca® Lightweight Expanded Clay Aggregate is formed by heating and firing natural glacial clay in a rotary kiln at temperatures up to 1150oC. This process transforms the clay into lightweight ceramic granules with a hard shell and porous core. With a bulk density of just 0.3 tonnes per cubic metre, Leca® Lightweight Expanded Clay Aggregate has excellent insulation properties, is free draining, fire resistant, frost resistant and chemically inert with no hazardous properties. Used as a lightweight aggregate fill in many civil engineering and construction applications Leca® Lightweight Expanded Clay Aggregate reduces the weight on weak substrates and against retaining structures by up to 75% over traditional fill and eliminates expensive settlement delays, is easily handled and quickly installed.

Leca® Lightweight Expanded Clay Aggregate was the perfect choice for the backfill to this special sensory pool. The Leca® Lightweight Expanded Clay Aggregate was brought to site in a pneumatic delivery truck and we were able to blow the material exactly into position with the truck some 40 metres away. This system saved us literally hundreds of man hours and gave us the perfect lightweight fill against the pool structure and above the pipework. We simply compacted the Leca® Lightweight Expanded Clay Aggregate into place and constructed the walkways,” said Mr Fallon.