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Building Obsolescence and Revitalisation 561
Upgrading thermal performance
Few of the existing 22 million homes in the UK operate close to the energy standards
expected and legislated for. This means that a large proportion of the domestic building
stock is in need of a thermal upgrade. This is also the case in the non-domestic sector,
where the majority of existing buildings fail to meet current standards for thermal insulation.
Upgrading (retrofitting) the thermal insulation of buildings requires a thorough
understanding of the existing building fabric. Failure to appreciate that many interventions
will change how the building breathes and reacts to changes in temperature may lead to a
deterioration of internal air quality and problems with condensation. Any interventions
must be considered in relation to the whole building and the detailing adjusted to suit the
physical personality of the building. Some of these issues have already been explored in
Barry’s Introduction to Construction of Buildings, Chapter 13. Typical interventions that can
be carried out without major disruption to the building users include:
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Improving the thermal insulation of walls and roofs
Replacing single glazed windows with double or triple glazed units
Installing insulated, air tight, external door sets
Improving the air tightness of buildings
Installing heat recovery ventilation systems
Installing solar collectors (solar thermal) and PV cells (electricity) on roofs
Replacing boilers with high efficient condensing gas boilers
Replacing lighting with low-energy fittings
It may also be possible to reduce the thermal bridging in some buildings, although this can
be technically challenging, highly disruptive and expensive unless it is done as part of an
extensive retrofitting exercise with users relocated during the work. The challenge for building
owners is that the payback period on investing in retrofitting buildings is lengthy. Thus
it is necessary to also look at the positive effect on user comfort and well-being, which is
not easy to allocate a cost.
Upgrading accessibility, usability and comfort
Alterations to facilitate disabled access are a major challenge for many building owners.
Changes in level and various widths of access may contribute to the character of a building,
but these features can, and often do, create barriers to access. Providing equal access for all often
requires structural alterations and careful detailing, which must be done sensitively if the character
of the building is not to be unduly affected. Equally the implementation of (non-intrusive)
fire detection and security equipment requires sensitivity to the building’s character.
Upgrading the usability of interior space and the overall comfort of the building users
is another concern. Buildings must be seen in the context of the society and the people
who interact with them; thus user feedback is crucial in formulating the design brief.
Asking users how much control they wish to have over their internal environment can be
instrumental in formulating design solutions. For example, the ability of users to have local
control over light levels, heating and airflow may influence their perception and comfort
of their internal space. These are important issues for the usability and comfort of building
users as well as for the operation of the building.