henno wrote:Which course within the Passive House Institute have you done?? and was it expensive??
Passivhaus Planning package is an accessible tool for designers and home builders. I haven't done any course directly in passivehaus, I get Dr Suzanne Theumer of the PHI to check my cold bridge calcs and any assumptions. There are established european norms and international Standards for calculating heat gains and losses such as EN 832, cold bridge calc methodology in IS EN 10211 using Therm for instance. The PHI arch/engineer then verifies the completed build. When you have 2 buildings certified, you are an accredited passive house designer. Alternatively there is a course in Strathclyde Glasgow in November, this will be repeated in Ireland in 2010. On commercial you can use IES software to design a building to meet the PHI benchmarks. Namely 15kWh/m2/annum for specific heat load, 10W/m2 for heat load and 120kw/m2/annum for overall energy, finally the most difficult criteria, 0.6 air changes per hour @ 50 pascals overpressure. Of course for commercial I have to get calcs signed off by a Cibse engineer.
Its very useful to be able to refer to space heat in quantitative terms, that way you can analyse say window alternatives to make the optimum choice. It takes the guesswork out of specification. One of the biggest issues with passive standard or low energy build, is that once you start to superinsulate, you can create a situation where you store up interstitial condensation problems for the future. This is why low energy builds use, cellulose, softboard, hemplime etc, natural hydroscopic materials, along with the likes of quinnlite and EPS. Insulation in the form of Phenolic an polyiso is out. All build ups need to checked with simulation programs like WUFI to assess condensation risk. We also use natural materials as they have better thermal inertia, this is especially important for roofs, which can easily overheat. So we're providing a service that takes the guesswork out of building, we also take the clunky boiler out too. The size of Boilers and chillers are an indication of the quality of design, so its nice to be able to say your building is a twelve, when building regs require 50.