Polypipe Ventilation products are available through five main brands, HR01 Heat recovery ventilation units that can recover more than 92% of a buildings heat. The Domus range of plastic ventilation ducting, wall outlets, duct silencers, flat channel ductiong, round pipe ducts including insulated ducting, flexible hoses and high performance extractor fans. FIREBRAKE Duct Fire Protection. The Base range range of slim-line extractor fans for domestic use and now Silavent ventilation products.