TeploTie, thermally insulating wall ties, have been used in an environmentally conscious project at a UK school . The new classroom and storage room at Hawridge & Cholesbury Church of England School, Buckinghamshire, has been designed to reduce energy and water usage by the new building’s users. The project also utilised many sustainable building materials.

TeploTie was used in a traditional brick and block wall with a 150mm cavity. The cavity was fully filled with mineral wool insulation. TeploTie was specified as the projects wall tie due to its low thermal conductivity. The wall has a calculated U-value¹ of 0.23 W/(m².K). With metal wall ties the U-Value would have been 0.25 W/(m².K). TeploTie improved the walls thermal efficiency by 9%.

Mark Tinker the project’s architect set out to make the final building sustainable through its basic building fabric. This was seen as being more important than incorporating the “bolt on gizmos” such as solar panels, wind turbines etc, often associated with sustainable design.

A full list of the sustainable design features of the project is kindly provided by the projects architect below.

Hawridge & Cholesbury Church of England School, Buckinghamshire

Sustainable features of the design

Mark Tinker MA DipArch RIBA

Energy Conservation

• higher insulation standards than required by regs to roof, walls and floor
• high thermal mass construction
• good natural daylighting
• good natural ventilation
• 150mm fully insulated cavity walls (mineral wool) with thermally efficient cavity ties
• low energy lighting
• occupancy sensors to lighting
• low energy glazing
• solar shading

U Values

• main masonry walls 0.23 W/(m².K)
• framed walls 0.27 W/(m².K)
• floor 0.14 W/(m².K)
• roof 0.11 W/(m².K)

Water use

• low water content dual flush toilet
• spray taps with auto shut off

Non toxic / renewable materials

• local clay stock bricks - Matthews machine made stocks, Matthews being a brickworks local to the site that produces really lovely bricks, which are FL (frost resistant and low effloresence)
• lime rich mortar (1:2:8)
• recycled aggregate blocks
• recycled newsprint insulation
• natural linoleum
• goat hair carpet (suitable for wheelchairs)
• non toxic paints
• naturally durable timber (larch)
• timber windows
• steel guttering
• clay drainage

Other

• breathing wall construction to bays

¹ Calculated using BRE approved software "U-Value calculator 1.10" and "BuildDesk 3.2 U" Software from BuildDesk Ltd

October 2008