Visqueen Ultimate HC BLOK is a highly flexible 0.5mm thick coextruded membrane, manufactured using Visqueen’s advanced barrier technology. Ultimate HC BLOK is suitable in brownfield applications that are affected by aggressive chemicals such as naphthalene, benzene, toluene, ehtyl benzene and zylene (BTEX). Made to comply with current guidance on Volatile Organic Compounds (VOCs) vapours and ground gases. Available in a large roll format to minimise jointing and to speed up installation times. Ultimate HC BLOK is flexible and puncture resistant. Conforms to CIRIA C748 and BS8485:2015.