With over 15 years’ experience in the field, Pacific Cast Stone chimney designers have seen and solved all the common (and not so common) flue and chimney installation problems. A few simple details is all we need to design a free, regs. Compliant installation. We can liaise with your installer before and during the installation to make sure it all goes to plan. When building a chimney on an existing building when it is not possible to run the chimney internally. When building a chimney internally in an existing building. The installation is quick and relatively easy.