*ACHIEVES 1 POINT FOR GOOD PERFORMANCE OR 2 POINTS FOR VERY GOOD PERFORMANCE UNDER BS8485 DEPENDING ON SIZE OF BUILDING AND GAS SCREENING VALUE. • HIGH RISK CHARACTERISTIC SITES • REGULATIONS COMPATIBILITY TABLE CIRIA 665 CHARACTERISTIC SITUATION 2 CIRIA 665 CHARACTERISTIC SITUATION 3-6 CARBON DIOXIDE HYDROCARBON VAPOURS & LIQUID DESCRIPTION Provoid 25 is a 25mm thick single-sided geocomposite that provides a void beneath floor slabs which, when connected to air inlets and outlets, allows sufficient air changes to dilute gases to safe concentrations when designed correctly. Provoid 25 can be laid in strips at predetermined centres or in a blanket as required and, being only 25mm thick, means there is a reduced dig when compared to a 200mm or 150mm blanket of stone. It is also extremely strong and flexible with a crush resistance of 250kpa and is supplied in rolls of 45m2; therefore large areas can be covered very quickly. Provoid 25 is flexible and can be laid horizontally and vertically to deal with awkward foundation arrangements. Because of its flexibility, it will cope easily with settlement under the slab without compromising the system. Forecheimer Term Ultimate compressive strength at yield A. Proctor Group can provide a design service from plans and site investigation reports. Please contact our technical desk for further information. Venting systems should be designed on a site specific basis. Roll Length

PROVOID 25 ACCESSORIES Venting System Components 6,000mm2 ventilation area 1: Ground Level Gully Vent Box* 2: Provoid Connector ‘T-Piece’ 3: Provoid (Geotextile side down) * Provoid Gully Vent Boxes need to be set in 150mm surround of no fines concrete. No vehicular trafficking should be driven over Gully Vents. TECHNICAL SERVICES • Consideration of Site Investigation Reports and Gas Monitoring Results so that advice can be supplied on the gas characteristics and protection needed on site • comprehensive range of membranes and venting systems to protect against Methane, Carbon A Dioxide, Radon,...