most important aspect of any
asphalt, paver or concrete driveway!
If the grading is not done properly you are most
likely to have a water problem.
You may have water going into the garage, standing
water near your house, or puddles in your driveway, even ponds on your
If your driveway has any kind of water problem,
then most likely poor pitch or grading was the key factor.
Driveways need to be pitched away from the house and when possible down
towards the street. It is always best to pitch the driveway in
more than one direction when possible.
For water to flow through pipe you need to have 1"
(one inch) of pitch for every 10' (ten feet) of length. But for water
to flow well on a driveway I use, 1 1/2" (one & one half inch) to
every 10' if possible, allowing for any imperfection or a porous mix.
What does this mean? For example, If your garage
floor is 100' away from the street, for water to flow to the street,
the garage floor must be at least 10" higher than the edge of the road
or street that you are paving to.
Ideally 15" or more to every 100' will make the
water flow even faster and make the paving job easier. 11/2" to every
General Rules of Thumb
Never install concrete, pavers or asphalt
perfectly level, it must be tipped slightly to allow water to run off
(unless it's indoors) this term is known as PITCH.
Minimum pitch is 1” to every 10’, which means
that if a level ten foot section of pipe is lifted 1 inch at one end,
water will flow out the low end of the pipe. (If the pipe is level
water will stay in the pipe).
Always try to have more than 1” to 10’ if
possible because driveways and walkways are not as smooth as the inside
of a pipe.
Tennis and basketball courts, patios, walks,
even gravel and stone driveways, anything out doors will need to obey
this rule of pitch, (except swimming pool installations which need the
water to stay).
When possible always try to pitch water away
from the house and towards the street. This of course will depend on
the elevation of your garage floor.
When possible always pitch in two directions,
for example front to back and left to right.
Drains and Drainage Systems
Just because your garage is lower than the
street does not mean you need some sort of drainage system. An
experienced contractor can pitch the water away from your garage door
and have the water flow around your house without having any problems
and without using a drain. Unless there is no place for the water to
Only install drains or drainage systems when
there is no other choice
Always try to avoid installations of drains if
they are not necessary.
Look for alternatives to drains that could fail and create maintenance
If you have no choice and do require a drain, then
the water table of your property will have to be considered. Some land
is on a high water table which will not provide good drainage.
Ledge can also be a problem when installing a
drain, not only when excavating for the drain but for drainage ability,
because water will not be absorbed by ledge.
Drainage systems will add a substantial cost to
your driveway project and there is no guarantee that the drain will
work efficiently enough to absorb a week long rain fall or rapid spring
thaw that might overwhelm your drainage system and cause it to back-up
into your garage.
Piping systems, overflow pipes and sump pumps may
need careful consideration because they can fail with frost and
clogging by leaves and debris. They may be fine for most of the year
until something fails and it can cause some problems down the road.
You will need a permit, and most likely be charged
to tie into a city or town drainage system if applicable. There may be
an ongoing cost associated with it but it would be the municipality's
responsibility to keep the drainage system functional.
These are just a few of the problems you can run
into with drainage systems and that is why I tell my customers to seek
alternatives when possible!