New Passivhaus triple glazed windows and doors have now been expertly fitted to the north elevation of 3 Passfield Drive (wall insulation will follow soon). The excellent thermal performance achieved by these windows and the draft-free fitting can be clearly seen in the thermal image of the north elevation below. Comparing the ground floor window of no. 3 to the neighbouring property on the left it is remarkable how much better our house is performing. The same can be said when considering the difference between the new front door of no. 3 and the front door of the neighbour to the right hand side. It is interesting to mark that although the neighbour to the right has replaced their windows with double-glazed windows which are performing much better than the single-glazed ones, they have not chosen a high-performance door, and their walls are now performing much worse than the windows. This image serves as a valuable lesson in the importance of retrofitting buildings properly as we are doing with no. 3 - so that the entire envelope (walls, roof , windows and doors) all work effectively together in retaining heat and minimising energy waste.


A thermal image of the north elevation of Passfield Drive indicating no.3.


Passfield Drive Thermal Image. South elevation indicating no.3.

Above is a thermal image of the south elevation of Passfield Drive (no.3 Passfield Drive to the far right). The heat being lost from these old single glazed windows is in stark contrast to the new triple glazed windows that have been installed to the north elevation. Interestingly, the high performance windows installed to the neighbouring property appear to be retaining the heat well but because they do not have the insulated frames of a Passivhaus window and have not been installed with draft-free seals (in the manner that the new windows of no. 3 have been) the heat loss to the perimeter of the window is clearly noticeable and somewhat negates the performance of the replacement window.

The picture below shows the trench around the property which is ready to be filled with external insulation. The thermal image shows significant heat loss from the foundations.

The thermal image below shows a hotter area at the bottom of the trench, we are unsure where this heat is emanating from but suspect that it is either where the ground is acting as insulation and storing the heat from the foundations or it is the heat of the ground

A thermal image of the bottom of the trench showing a hotter area where the foundations touch the soil.


A photograph of the area in the thermal image above

Last week the Muhammads asked the contractor to stop work on HRV duct routes and internal insulation. Unfortunately although these aspects of the design had been on the drawings from the beginning the Muhammads were surprised to see the work being done. Their concerns were that they would loose valuable space in their bedrooms and living rooms. These aspects of the retofit are fundamental to the success of the project and unfortunately could not be removed. After meetings with the Muhammads and their social landlord we have come to a compromise to reduce the amount of insulation internally and relocate one of the duct routes to a location that is more agreeable to the Muhammads. Work is now proceeding on site.


Daffodils appearing in the front garden at 3 Passfield Drive. Mr Muhammad on the left with two of his sons.