1. Labour saving equipment is often difficult
to use due to the physical limitations of many renovations. In those
cases that means that only hand operated equipment can be used.
Think of excavating a basement by hand using a conveyor belt or
wheel barrel to remove the dirt. Time consuming and very costly!
2. Accessibility for excavation equipment
is often limited. The size of equipment used is smaller taking more
time - and time is money.
3. In many renovations the distances required
to move excavated materials add costs. Most additions take
place at the rear of the house.
4. Renovations often involve removing interior
or exterior load bearing structural walls. This creates the need
for shoring and bracing to hold up the building while structural
changes are being made.
5. In renovations material handling becomes
more costly. Moving concrete by wheel barrel instead of pump truck,
lumber by hand instead of by forklift or carrying drywall into the
house by hand instead of by boom truck are all time consuming.
6. Both on the interior and exterior of
the house there is a large amount of cutting and patching and attempting
to match the existing conditions. In many cases this gets so costly
that it's more economical to remove entire walls rather than create
many new door and window openings. This sort of trade-off has to
be carefully analyzed.
7. The cost to protect completed work can
be significant since the "normal" sequence of new construction usually
cannot be followed.
8. There are none of the economies of scale
usually associated with new construction. In renovating very often
small quantities are required. This increases both material and
labour unit costs.
For example the stucco unit cost (per square
foot) for 100 square feet is higher than for 2500 square feet. The
same holds true for many other material per unit costs (flooring,
concrete, mouldings etc..).
9. Very often with only small work areas
available at a given time, job scheduling between trades becomes
difficult and subcontractor quotations may reflect the excessive
start-up and shut-down phases of the job.
10. Dust protection to adjoining non-construction
areas can involve substantial special protection and alter usual
construction methods.
11. Renovations can experience delays due
to unexpected conditions discovered during demolition or removal.
These delays ultimately increase construction costs.
12. Plumbing piping and heating/cooling
ductwork runs can be difficult to access. Electrical wiring may
have to be snaked through finished walls and floors.
13. Matching "existing conditions" can
be difficult because materials may no longer be manufactured. Substitutions
can expensive.
14. Weather protection of existing structure
often require additional temporary structures.
15. On small projects its often necessary
to pay a tradesman for a minimum of four hours for a task that is
completed in one hour.