John Gilbert Architects were approached by the Pebble Trust to consider the lack of quality and sustainability in the construction industry. With 51% of new-build houses having major problems* it might seem that new building would be a good place to start. However, when we took a step back to look at the housing stock overall, and the need to achieve energy efficient, healthy and sustainable housing for everyone, we felt that the greatest need would be to consider the vast number of existing homes across the country.

The timing coincides with Scottish Government investment intended to make existing housing more energy efficient, with the twin aspirations of reducing carbon dioxide emissions and reducing fuel poverty. This makes sense and the investment is extremely welcome. There is no doubt that current retrofit efforts are saving energy and improving comfort for thousands, but on the other hand many renovation projects are not as effective at saving energy as they could be.

Moreover, they can have negative effects on the comfort and health of occupants, the condition and durability of the buildings, and in some cases on the conservation value of the buildings. There are many reasons for this, and in this guide we identify ten aspects which could lead the industry towards far more effective, healthy and robust solutions.

The first important difference between our Sustainable Renovation Guide and others is that we aim for a balance between energy efficiency, the comfort and health of occupants, and the durability and condition of the building fabric.

Broadening the focus beyond energy efficiency does not mean we do not value it. The opposite is true. The difference is that while most conventional guidance is based on modelling tools used to calculate energy consumption in buildings, our guidance is based on observations and investigations of ‘real’ energy consumption, measured and monitored in real buildings once completed and inhabited. We are interested in what actually improves energy consumption, rather than what purports to improve energy consumption on a spreadsheet.

Almost all studies into how buildings perform in reality acknowledge that the way people behave in buildings makes as much, if not more difference than the technical aspects of the buildings. Thus in this document we place considerable importance of engaging with people.

Lastly, we acknowledge the value that the conservation or heritage sector has brought to the understanding of how to work with existing buildings. There is a great deal written about this, but it is usually confined to publications aimed at those who own or work with listed buildings, whereas the advice is relevant to most existing buildings. This covers the last three points listed below.

In summary, the ten ways in which the guidance differs from most conventional advice advice are:

1. seeking a more effective approach to energy efficiency
2. taking account of the comfort and health of people who live in buildings
3. avoiding problems which could lead to building fabric decay and deterioration
4. favouring details based on real, measured performance, rather than modelled predictions
5. highlighting the need for more co-ordination and inspection, and for better workmanship
6. integrating considerations of moisture in buildings
7. proposing a much closer level of engagement with people, particularly occupants
8. acknowledging the different construction principles and materials found in older buildings
9. placing value on maintenance
10. suggesting that the ‘significance’ of individual buildings should be integrated into routine retrofit assessment.

The guide discusses these aspects before providing detailed examples of how to apply the ideas in practice. A free PDF of the guide can be downloaded for free from the SEDA or the Pebble Trust websites, .A hard copy of the guide can be purchased for £10 plus P&P from the same sites.

*A 2017 YouGov survey for the housing charity Shelter found that 51% of homeowners of recent new builds in England said they had experienced major problems including issues with construction, unfinished fittings and faults with utilities.