Converting redundant buildings can save on new construction costs but also carries high financial risks due to the unpredictability of renovating existing structures. Conversions require contingencies since the full renovations needs are difficult to foresee. Proper planning including thorough structural surveys and a comprehensive design brief are necessary to help manage risks. However, conversions still involve uncertainties that can lead to cost overruns and jeopardize project completion or profitability if severe problems arise.

1. Conversions and rehabilitation of
redundant buildings
Why do it and is it worth it?

2. Renovation vs. Conversion
• Renovation
– Renewal
– All buildings need renovation if they survive
long enough
• Change of fashion, change of standards, wear
and tear
• Conversion
– Redundancy
• Buildings are converted because they no longer
serve a useful purpose in their original form,
they are redundant

3. Why convert a redundant building to a new use?
• May be perceived as cheaper than new
build
• Might “get around” planning restrictions
• Irrational emotional attachment to a
redundant building

4. Cost saving?
• Will it really be cheaper to convert?
– Standard cost formulae don’t work
– The extent of work needed is very hard to
predict
– Builders’ estimates are almost
meaningless and quotations impossible to
enforce.
– Extra costs will be inevitable
• Conversion is financially a highly risky
business

5. Financial returns on investment
• It is possible to make a return on
investment (ROI) in a conversion, but it
is not guaranteed and often the return is
not as great as anticipated.
• If a building owner puts in large
amounts of personal time in the
conversion and costs this at £0, any
return ROI will be artificially inflated

6. Case Study; Hill Paul Building, Stroud
• Former textile factory and offices, condemned
as unsafe in 2000
• Due for demolition in 2002
• Extended and converted in flats in 2003
• Some income from permitted additional
housing around the site makes the scheme
financially viable
2002
2003

7. Would you buy someone else’s conversion?
• It is important to remember that the
market for barns/mills/oasts needing
conversion into houses may be larger
than the market for barns/mills/oasts
that have been converted into houses

8. Planning restrictions
• New building in an area might be forbidden or
severely restricted:
– Conservation areas
– Rural areas
• Planning design guides for new buildings may
make them too expensive to be viable
• In these cases, conversion of an existing
building may be a route to development
• Be aware of the planning implications if your
building is listed

9. Emotional commitment
• People like to convert old buildings, especially
for private houses
– It can put them in touch with
traditional craftsmanship
– It allows them to own an
old “house” which they
may not have been able to
afford otherwise
– They can put their own work into a conversion
project in a way that may not be possible in a new-
build house.

10. Case study: Clavell Tower Dorset
Landmark Trust restoration and conversion

11. Case study: Brunel goods shed at Stroud Station
• Last remaining goods shed designed by I. K. Brunel
• New use has been sought for years, but what can
you do with a large single storied building on a
railway line with no parking?
• It has been re-roofed, repaired but no use can be
found for it.

12. What are the costs of conversion?
• Impossible to predict in advance, which
is what makes it so difficult to estimate
– Is the structure adequate for new loads?
• Foundations – depth, strength, existence!
• Walls – stability, strength, durability
• Roof and floor timbers – decay, strength,
rigidity
– Thermal insulation
• It is both a legal and comfort requirement for
buildings to be energy efficient. A building
converted to a new use will have to match the
required insulation standards of the new class.

13. Safety in fire
• Conversion from non-residential to
residential raises immediate problems
of fire safety
– Any building containing sleeping
accommodation must meet stringent
standards of fire resistance and adequacy
of escape routes. These can be difficult to
meet in an existing building.

14. Safety in fire 2
• Conversion from 2 stories to 3 or more stories
– There must be adequate protected escape routes
for people on the upper floors. This is a block on
many loft conversion proposals
• Conversion of one building in a group to
residential use may have a knock-on effect on
nearby buildings, such as agricultural
buildings
Protected passage
from second floor
to exterior needed

15. Services
• Existing services may be inadequate or
inappropriate for new uses, or just non-
existent.
– Having to replace old wiring, lead pipe
work and cracked drains can be expensive
– It is far more expensive to thread new
pipes, drains and wires through an existing
building than it is to build them into a new
building.
• Utility services may be non-existent and
can be cripplingly expensive to install.

16. Designing a conversion
• The design process is much the same for a
conversion as for a new building
conception >> development >> realisation
• Conception is fundamentally a forecasting
process, you consider the outcome first.
• Development is the process of answering the
question of how you are actually going to
create this new building from the existing one
• Realisation is actually producing the building,
often an act of hope and discovery…

17. Conception
• Why are you converting?
– Be very clear and robust in answering this:
• Is it simply a personal desire to use the converted building?
• Do you want, or need, to make a ROI?
• Are you aware of the complexities of converting?
• Do you have adequate resources to cover unexpected costs?
• Are you the client? If not, has the client understood and
accepted the risks and uncertainty of conversion?
• The brief
– A detailed, comprehensive design brief needs to be
developed, which is effectively the “mission statement” for
the project.
– To prepare a conversion brief, detailed structural and
measured surveys will be needed

18. Development
• The heart of the design process, where ideas
are created and tested against the brief.
• This is a reiterative process. Problems which
arise during the design development may
require a return to the brief for
reconsideration.
• The “end” of the development process is a
set of working documents (both text and
drawings) which guide the realisation. These
will become the contract documents.
• Contract documents for conversions will be
subject to change

19. Realisation
• Physically creating the finished
conversion of the building.
• Problems which arise during
construction may require amendments
to the design drawings. This is
particularly true for conversions.
Problems will arise.
• If problems are so great that you have
to revisit the brief, you have a potential
financial disaster on your hands. Many
conversions are never completed.

20. Summary
• Be sure you understand why you are
converting
• Be aware of the unpredictability of conversion
• Make sure that sufficient contingency funds
are available for dealing with unforeseen
problems
• Be realistic in the costs of converting and the
true return on investment.
• Research the market for converted buildings
to get an idea of the true value of the finished
project.