Temporary Services |
and Layout | >>Excavation
Options | Subrough
Plumbing & HVAC | Dampproofing,
Waterproofing and Window Wells | Water
and Sewer Laterals | Foundation
Drain, Backfill and Rough Grade |
is the process of removing earth in order to build
a basement or foundation. Generally a backhoe, excavator
or front loader is used to excavate for a basement.
A front loader or bulldozer can be used to excavate
for a stem wall (crawl space) or a slab on grade foundation.
Besides digging a hole for the house, the excavator
will backfill, install water and sewer laterals, rough
grade, finish grade and provide gravel for flatwork.
Before you excavate you will need to have the foundation
lines and underground utility lines marked. The underground
utilities such as gas, water and electricity must
be marked by a utilities locating service. A utility
locator service will mark the utilities with paint.
If you don't have
the utilities marked you may be legally liable and/or
fined if you hit an underground utility. Check your
local laws before proceeding. Remember that you will
need 2'-4' over dig around the perimeter of the home.
This gives you plenty of room to get the footings
and foundation in. Make a plan with the excavator
to spread the dirt so that the concrete truck has
access to pour the footing and foundation. If the
concrete truck can't get close enough to the hole
you will have to hire a concrete pump ($$$).
The depth of your
foundation will be determined by several factors:
the local frost line, required foundation above grade,
level of the sewer line, garage access, and other
Lift up the sewer cover and check the level of the
street sewer line with a laser or transit level. Once
you have that reading, check the level of your property.
Your basement floor needs to be higher than the level
of the sewer (for waste water to drain). Otherwise
you'll need a sump pump to remove sewage from you
house. Work with your excavator to make sure that
the depth of the hole is correct. Generally you'll
need at least 1 foot of foundation above rough grade.
For crawlspace foundations and slab on grade foundations
the sewer is not a problem.
A contract would
generally contain the following items:
• Price for excavation (usually charged by the
soil conditions, and the square footage of the home,
or size of the hole). However, some excavators charge
by the hour only, because they aren't sure how much
time certain hole will take due to varying soil conditions.
• Description of the work to be performed. Some
excavators will offer a package deal for the complete
excavation services, excavation, backfill, water and
sewer lateral, Rough grade and finish grade.
• Cost for change orders
• Hourly rate for work not included in the contract.
Double check excavation
marks. Check that the setback from the property lines
is correct. Check that the dimensions are correct,
including the overdig. Make sure that the orientation
of the house concurs with the plot plan. Plan with
you excavator where the soil will be place during
excavation and how you will gain access to the footprint
to deliver materials, especially concrete placement.
• Safety is
a major concern while digging a hole and after the
hole is complete. Children are attracted to large
piles of dirt and a large hole to play in. Make sure
that you secure the site from unwanted traffic. Most
states will make the property owner liable for injuries
which occur on your property, unless precautions are
taken to secure the site.
• Make sure that your footing and foundation
sub is ready to begin immediately after the excavation.
• It costs
extra to haul away fill. Try to minimize the amount
of fill that is hauled away by spreading the fill
out around the site. If you must haul fill off site,
try and find someone who needs fill and is willing
to pay for the hauling.
• Plan with the excavator to create a path or
access to the footings and foundation so that he will
make the hole easily accessible for the concrete truck,
otherwise you may have to hire a pump truck for the
footings and foundation.
their work by project bid or by the Hour. Try and
get a bid for the entire project which includes, excavation,
backfill, installation of water and sewer laterals,
rough grade, finish grade, and placement of gravel
for concrete flatwork. This way you will know the
exact amount for all the excavation.
If soil conditions are unknown, it is more likely
that the excavator will want to work an hourly agreement.
They reason that this is most fair to them and to
the owner builder because without knowing soil conditions
it is impossible to calculate a fair bid. If you make
an hourly agreement keep good records of the work
performed on site by each type of machine. Also get
in writing the price per hour for each piece of equipment.
Excavation equipment has built-in time meters making
it is easy to track usage.