PHPP (Passive House Planning package) is an energy balance tool used to model all aspects of a building to assess how it will perform once constructed.

We can build a PHPP model from planning stage to help with the design process, improve the efficiency of form and assess overheating risk associated with glazing, shading and orientation. This can then be modified over time once further details, construction methods and specifications have been confirmed.

Modelling a design in PHPP is not just for clients looking to certify a building to the Passive House standard. It is a great tool to inform on potential space heating loads and to review overheating risks which can potentially happen in any new build or retrofit. It can help direct the selection of construction techniques and insulation requirements for walls, roofs, windows etc. to determine where best to allocate funds for the best performance return.

We initially create a 3d model of the thermal envelope in Design Ph where we can import local climate and landscape data and model shading from the environment, trees and nearby buildings. This is then exported into PHPP where additional data can be added to provided the most accurate model.

Passive House principals and PHPP modelling are also used for the AECB building standards as well as the LETI retrofit standard, but each has its own slightly varying target criteria.

If you are interested in building a certified Passive House we can assist and work with an approved certifier to gain certification of the project.

Design Ph and PHPP was used at the early stages to fully understand the impact of heat losses and gains in a house that the client wanted gain Passive house certification. U values for the build were modified along with the glazing and shading to ensure that the house would not overheat and still meet the Passive House criteria for heat load. A number of mature deciduous trees on site would provide shade in the summer but allow solar gains into the building in the winter when leaves had dropped. Additional brise soleil and external blinds were modelled to reduce overheating through large south facing windows and the model stress tested using guidance on best practice from the Passive House Trust.

A PHPP (Passive House Planning Package) Energy balance model of a historic listed building was built to test options for improvements to the building fabric and help size an air source heat pump. Each different colour in the model represents a variation in building fabric and performance value.  Site measured air infiltration was also entered into the model as a baseline figure and to demonstrate how improvements in airtightness would impact energy consumption. With older and historic buildings energy efficiency improvements can only be undertaken if there is an acceptable risk to building fabric and historical significance.