Ross Elliott Surveying

Low energy design


Passivhaus is the most widely recognised international energy and comfort standard for buildings, with a rigorous assessment and commissioning system. Passivhaus principles put occupant wellbeing front and centre to ensure a supremely comfortable and healthy living environment, with steady interior temperatures and fresh air supply. A Passivhaus building aims not to use as much energy in the first place by being effectively sealed against the elements. The actual construction methods of Passivhaus buildings will vary but they will all have some features in common, including:

Far greater insulation than typical UK properties.

–  Triple glazing, with insulated frames.                                                                                                      – Impressive airtightness levels (around 20x more than a standard build).                                        – Mechanical ventilation, with heat recovery.

We use the ‘Passivhaus Planning Package’ (PHPP) and ‘DesignPH for Sketchup’ to assess and test options for design, whether they are being Passivhaus certified or not. The ability to easily compare energy performance against cost and aesthetics for a range of design options and identify whether one design concept out-performs another is a powerful tool, removing guesswork and providing reassurance and confidence to our clients.

If you’re considering a sustainable build project, do get in touch. Whether you’re looking for a partner to guide you through the process from conception to completion, or to work with your architect and take on the construction to the standard required, we’re just a call away.


Retrofitting is the process of improvements that make a property more energy efficient. This cuts energy bills, carbon emissions and improves comfort levels.

I believe in a fabric first approach through improvements in airtightness, insulation levels and thermal bridging. This can be more difficult to achieve but in most cases this will result in a better return on an investment than a bolt on technology, such as solar panels.

When it comes to retrofitting, there are very few standards available, and while the Passivhaus retrofit standard, EnerPHit, is a brilliant aspiration, it can often be unattainable and may be too stringent for most homes in the UK. The AECB Retrofit Standard offers a pragmatic approach to the energy demand targets, which are still potentially lower than current UK new building regulations.

The main difference that sets the AECB standard apart is that it recognises that every home is unique and focuses on managing retrofit risks to avoid unintended consequences. The self-certification process offered by the AECB Retrofit Standard also helps to keeps costs down.

By using the Passivhaus Planning Package (PHPP) software and modelling as a design tool, the AECB Retrofit standard ensures good thermal and comfort performance, avoiding the ‘performance gap’ of so many retrofit projects.

I am a qualified Passivhaus Designer and I can provide clear independent advice and support to help you plan, procure and deliver your retrofit project to a high standard. What is involved:

  • An initial discussion by phone or email.

  • A consultation at your home to discuss what may be required, followed up by a brief email report.

  • If you wish to proceed with a retrofit then I can undertake a detailed survey of your property, so I can prepare a detailed 3D model, floor plans and elevations.

  • Using the Passive House Planning Package (PHPP) I can model the energy demand of both your existing house and an improved scenario.

  • To ensure that the information within PHPP is accurate, I can organise for an initial airtightness fan test of your home and carry out thermal bridge calculations using THERM to reduce or design out heat loss and low surface temperatures at problem junctions. Ventilation and heating designs can also be undertaken. All this data is fed back into the PHPP model.

  • Using all of the information a whole house plan can be prepared, which is an energy efficiency improvement strategy for the entire house. If budgets are tight, there are usually smaller, easier stages that can be undertaken first but it is useful to keep your whole house strategy in mind when undertaking any improvement works on your home. 

  • Depending on your requirements, I can prepare works specification for agreed improvements and obtain quotations from selected contractors. Works can also be managed on site if required.

  • Improvements can be implemented in a phased approach over several years if needed, although this can introduce complications for certain tasks, especially airtightness.