ecoSmart-Fire Help
Index
What
is ecoSmart Design Software?
What is
ecoSmart-Fire?
How does
ecoSmart-Fire work?
Getting started
Step by step process
Reduce fire hazards by…
How do I…
- Create a lot
- Set lot orientation
- Add a
house
- Add a garage
- Add pavement
- Add
trees
- Move a
tree
- Remove a tree
- Change size of a tree
- Raise a tree crown
- Add a second story
How do I know when I’m firesafe?
What this model will not do
What about buttons that don’t work?
Menu options
About
What is ecoSmart Design Software?
ecoSmart Design Software is a
web-based program designed to
evaluate trade-offs between
different landscape practices on
residential parcels. It is designed
to be interactive, and allows you to
re-configure your landscape and
instantly see the impact on
landscape water use and stormwater
runoff (ecoSmart-Water), energy use for
heating and cooling (ecoSmart-Energy),
and fire safety (ecoSmart-Fire).
ecoSmart-Fire,
version 1.0 is completed and the
other modules are under development.
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What is ecoSmart-Fire?
ecoSmart-Fire is graphical software
that allows you to interact with the
program to visualize fire hazard
effects of changing your landscape,
such as moving a tree, replacing one
tree with another, or raising tree
crowns. It will answer the question:
How will landscape changes affect my
home’s fire hazard?
Some background…In the United
States, 42 million homes are located
in the wildland-urban interface.
Landscaping on these properties
directly influence the threat of
loss in fires. Pre-fire actions by
individuals responsible for the
design and maintenance of these
private properties can prevent
disasters. Federal, state and local
agencies have developed guidance for
improving the fire safety of
properties in the wildland-urban
interface, but this general guidance
may conflict with the desires of an
owner for the appearance of the home
exterior, use of the land, views,
privacy, and wildlife habitat.
ecoSmart-Fire is an interactive and
flexible graphical-tool designed to
assist residents identify ecoSmart-Fire
choices while considering the ways
to retain native fuels, irrigate the
landscape, and insure privacy.
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How does ecoSmart-Fire work?
ecoSmart-Fire is software for
estimating the fire risk to a
structure from nearby trees and
other landscape vegetation. Version
1.0 incorporates a method to
estimate the risk from fires through
ignition by radiant heating.
Three principal factors are
responsible for structure ignitions:
- flame radiation
- flame
impingement – convection, and
- firebrands (burning embers).
Radiation and convection involve
the transfer of heat directly from
the flame. Unlike radiation heat
transfer, convection requires that
the flames contact the structure.
Firebrands involve the aerial
transport of burning materials to a
combustible fuel receptacle
(structure roofing, open vents,
etc.) from vegetation or other
burning materials. Ignitions from
radiation (given an exposed
flammable surface) and from
radiation heat transfer depend on
two aspects of the flame: 1) the
radiant heat flux to a combustible
surface and, 2) the duration (length
of time) of the radiant flux. The
radiant heat flux depends on the
flame size, flame-structure
distance, and how much the
combustible material of the
structure is exposed to the flame.
Whenever the flame length, 1-2
minutes in duration or more, is
equal to or more than the separation
of combustible vegetation from a
structure, there is a high
probability of structure ignition.
Of the possible modes of home
ignition and destruction, the most
is known about radiation. For
example, radiative heating of a
surface is additive; therefore, the
radiative heat flux at a position on
the surface, from two identical
burning objects oriented similarly
with respect to that position, is
just twice that of one of them. In
addition, radiation becomes a more
dominant transport mechanism as
fires become larger. Crown fires,
which burn hot and spread rapidly,
are well-known examples of fires
where radiation is a dominant mode
for fire spread. Therefore, this
mode of ignition was selected to be
the first to be quantified in the
ecoSmart-Fire model. ecoSmart-Fire Version 1.0
incorporates a simple model of
thermal radiation transport from
trees to structures using exterior
material ignition properties to
assess the risk of ignition from
landscape plantings. Altering the
size and location of trees alters
the fire risk to the structure.
To account for uncertainties that
can exist in the characterizations
of burning trees and ignition
properties of exterior materials, as
well as other factors, such as wind
or fuel moisture content, the
approach taken in ecoSmart-Fire is
conservative. This is typical of all
areas of engineering and design
where “factors of safety” and
conservative estimates of important
information compensate for lack of
exact knowledge. ecoSmart-Fire examines
the “worst probable case scenario,
to assess the vulnerability of a
structure to fire.” It is
well-known, for example, that the
likelihood of ignition of a
structure depends both on the
magnitude of the incident radiative
heat flux, and on the duration of
this flux. In order for ecoSmart-Fire
Version 1.0 to execute quickly, the
effects of burning duration have
been eliminated from the ignition
model. Rather, each burning element
(tree, shrub or other nearby
structure) is assumed to be burning
at its peak value simultaneously,
and ignition of structure is assumed
to occur if the value of the thermal
radiative flux exceeds a critical
value that depends on the exterior
materials.
Since ecoSmart-Fire Version 1.0 has
only implemented a model of ignition
by thermal radiation, other
important threats have been set
aside for modeling and inclusion in
later versions. Therefore, the
approximations noted above represent
limitations of Version 1.0. For
example, ecoSmart-Fire Version 1.0 does
not include the effects of ambient
winds, burning brands and heat
fluxes from nearby burning
structures. Inclusion of these
effects will require additional
research, data, and development of a
much more sophisticated mathematical
model.
Even though many trees are used
in the energy and hydrology
sub-models of ecoSmart, fire data
are available only from experiments
with Scotch pine and Douglas fir
trees at this time. These limited
fire data have been used in
ecoSmart-Fire
Version 1.0 as though the data were
appropriate for all tree species,
with no experimental evidence
currently that such extrapolations
are valid. Therefore, predictions
obtained in ecoSmart-Fire version 1.0
related to pine or fir trees have
much more validity than those
related to other trees.
The fire experiments conducted to
measure burning characteristics of
conifers, used cut dry trees. It is
well known that low moisture content
of trees, shrubs or other vegetation
is critical to ignition and burning.
In fact, high moisture content will
prevent an individual tree from
being ignited at all. The
empirically derived formula from
Babrauskas and Strauss, has been
incorporated into ecoSmart-Fire Version
1.0 to help account for
moisture-related effects in the
burning vegetation model.
Although very limited as noted
above, ecoSmart-Fire Version 1.0 is an
important first step in providing a
simple, but visually compelling,
method to estimate the relative risk
of home ignition from nearby burning
trees. Given the present state of
understanding of WUI fire, the
manpower invested in developing and
implementing a Web-based model, and
the limitation on computer resources
implied for such a Web-based model,
ecoSmart-Fire Version 1.0 is probably the
best model that could be
constructed.
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Getting started
Welcome to ecoSmart-Fire 1.0. This
educational tool will help you
visualize the fire hazard associated
with different configurations of
trees around your home. It does not
include many of the complexities
associated with structure ignition
and fire spread, so it should not be
used as the sole basis for landscape
decisions. However, it is very
useful for seeing how trees of
different sizes and numbers
influence fire hazard at different
locations around your home.
To get started you will need to
get measurements for your lot, trees
and house.
- Lot – Measure the
length and width of your lot. This
is most easily accomplished by
pacing and recording the information
on a piece of graph paper. Note
which direction is north and
estimate the percent slope you have,
with 0% being flat and 90% vertical.
If your lot is wider on one end than
the other, measure both widths. If
your lot is an irregular shape, come
as close to a rectangle or pie shape
as you can with the measurements.
Also, take measurements of your
driveway and sidewalks.
- Trees – You will need to
locate each tree on your lot. This
will require two perpendicular
measurements for each tree. The
first will be to the nearest lot
line and the second will be from
your house or another lot line. To
place a tree on the lot you will be
asked to select the age or dbh
(diameter at 4 ½ feet above ground)
of the tree. If you select diameter
you will need the following
measurements: tree diameter, total
tree height, and approximate width
and height (distance from first limb
to top) of the tree crown. Measure
or estimate as close as you can.
- House – Take measurements for
your house and garage. Start with
the largest rectangle or square
portion as possible. Take separate
measurements for the garage and each
wing of the house. The house, garage
and wings will all be added
separately to the lot.
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Step
by step process
To find out how to ecoSmart-Fire your
home is follow these steps:
- When
the web site window opens up you
will see a smaller Lot Properties
window. Select rectangle or
trapezoid. Set your lot slope to the
correct percentage. Set the length
and width of your lot. Select the
grid size you desire. And finally,
set the default ground cover to the
appropriate cover. Click OK.
- To set lot orientation, click
on Lot in the upper left hand
corner. Click on Orientation and
either select a basic orientation or
use the button that allows you to
set the exact orientation. Set
orientation and click OK.
- To add your house, click on
Buildings in the upper left hand
corner. Click on “add wing” in the
drop down window. (There is no
feature to add a house.) Set the
length and width. Select the
appropriate number of stories and
check/uncheck air conditioned. Click
OK and move your cursor to the lot.
Position the house so it is in the
proper location. Click the left
mouse button to set it in place.
- Click again on Buildings/add
wing to add any additional wings to
your house. Set the length and
width. Check/uncheck air
conditioned. Click OK and move your
cursor to the lot. Position the wing
so it is in the proper location.
Click the left mouse button to set
it in place. Repeat for all wings.
- Click again on Buildings/add
wing to add the garage. Set length
and width. Check/uncheck air
conditioned. Click OK. Drag garage
in place.
- Click on Lot/pavement
to add driveway and sidewalks. Set
length and width. Click OK and drag
in place.
- Click on Add Landscaping/trees
to add trees to the parcel. Under
Select Species, select the
appropriate tree. Select age or dbh.
If you chose age, set the correct
age, click OK and drag your first
tree to the proper location. Repeat
until you have placed all of your
trees. If you chose dbh, set the
correct diameter, click OK and drag
the tree to the proper location.
Repeat until you have placed all
trees.
- If you want to be more precise
with the dimensions of your trees,
select dbh and then click on
Advanced. Set tree Height, Crown
Diameter, and Canopy Height to your
exact measurements. Select Water
Use. Click OK and drag trees in
place. Repeat process for each tree.
Continue until you have positioned
all your trees. This completes the
creation of your parcel. The color
of the slider bar only provides you
with an indication of how
ecoSmart-Fire
your home may be. If the bar is
green you may be OK. If the bar is
yellow there may be a few simple
things you can do to change the
color back to green. And if the bar
is red your home is probably not
ecoSmart-Fire, and you will need to take
some more difficult and expensive
steps to reduce the fire hazard. Do
not rely on this program to predict
the fire safety of your home. See a
professional fire expert. The
results you get with this computer
tool are merely an indication of
what might happen to your home in
the event of a fire. Many other
factors need to be considered when
making fire hazard decisions like
fire weather and neighboring parcels
for example. Please seek further
assistance if you are concerned.
- You are now ready to
experiment with various practices to
reduce the fire hazards on your
property. Remember that changes in
vegetation result in changes in fire
hazard. Go to Reduce Fire Hazards.
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Reduce fire hazards by…
- Removing a tree that is too
close to the house – click on the
tree you want to remove and drag it
off the parcel. Click again.
- Seeing how a tree will work in
another location – click on the tree
you want to move and drag it to the
new location.
- Removing and replace
a tree – 1) click on desired tree
and drag it off the parcel. Click
again. 2) click on Add
Landscaping/trees and change dbh. If
you have selected the Advanced
option, click on Advanced and repeat
the process above for adding trees.
Reposition the smaller tree in the
same position as the one just
removed.
- Raising a tree crown –
click on Add BMPs in the upper left
hand corner and select crown
raising. Set bottom of the canopy to
the desired height. Set desired
distance from the house. Click OK.
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How do I…
- Create a lot – In the Lot
Properties window, select rectangle
or trapezoid. Set your lot slope to
the correct percentage. Set the
length and width of your lot. Select
the grid size you desire. And
finally, set the default ground
cover to the appropriate cover.
Click OK.
-
Set lot orientation –
Click on Lot in the upper left hand
corner. Click on Orientation and
either select a basic orientation or
use the button that allows you to
set the exact orientation. Set
orientation and click OK.
- Add a
house – Click on Buildings in the
upper left hand corner. Click on
“add wing” in the drop down window.
(There is no feature to add a
house.) Set the length and width of
the largest portion of the house
that is square or rectangular.
Select the appropriate number of
stories and check/uncheck air
conditioned. Click OK and move your
cursor to the lot. Position this
portion of the house so it is in the
proper location. Click the left
mouse button to set it in place.
Click again on Buildings/add wing to
add any additional wings to your
house. Set the length and width.
Check/uncheck air conditioned. Click
OK and move your cursor to the lot.
Position the wing so it is in the
proper location. Click the left
mouse button to set it in place.
Repeat for all wings.
- Add a garage
– Click on Buildings/add wing. Set
length and width. Check/uncheck air
conditioned. Click OK. Drag garage
in place.
- Add pavement – Click on
Lot/pavement to add driveway and
sidewalks. Set length and width.
Click OK and drag in place.
- Add
trees – Click on Add
Landscaping/trees. Under Select
Species, select the appropriate
tree. Select age or dbh. If you
chose age, set the correct age,
click OK and drag your first tree to
the proper location. Repeat until
you have placed all of your trees.
If you chose dbh, set the correct
diameter, click OK and drag the tree
to the proper location. Repeat until
you have placed all trees. If you
want to be more precise with the
dimensions of your trees, select dbh
and then click on Advanced. Set tree
Height, Crown Diameter, and Canopy
Height to your exact measurements.
Select Water Use. Click OK and drag
trees in place. Repeat process for
each tree. Continue until you have
positioned all your trees.
- Move a
tree – click on tree you want to
move and drag it to the new
location.
- Remove a tree – click on
tree you want to remove and drag it
off the parcel. Click again.
-
Change size of a tree – 1) click on
desired tree and drag it off the
parcel. Click again. 2) click on Add
Landscaping/trees and change dbh. If
you have selected the Advanced
option, click on Advanced and repeat
the process above for adding trees.
Reposition the larger/smaller tree
in the same position as the one just
removed.
-
Raise a tree crown –
click on Add BMPs in the upper left
hand corner and select crown
raising. Set bottom of the canopy to
the desired height. Set desired
distance from the house. Click OK.
-
Add a second story – click on
Buildings/add wing and select 2
stories. Click OK.
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How
do I know when I’m firesafe?
The color of the slider bar only
provides you with an indication of
how ecoSmart-Fire your home may be. If
the bar is green you may be OK. If
the bar is yellow there may be a few
simple things you can do to change
the color back to green like raising
the crowns of trees within 20 or 30
feet of your house. But if the bar
is red your home is probably not ecoSmart-Fire, and you will need to take
more difficult and expensive steps
to reduce the fire hazard, like
removing trees. If your bar is not
green you should find a qualified
professional to help you determine
which trees to prune or remove. Do
not rely on this program to predict
the fire safety of your home. See a
professional fire expert. The
results you get with this computer
tool are merely an indication of
what might happen to your home in
the event of a fire. Many other
factors need to be considered when
making fire hazard decisions like
fire weather and neighboring parcels
for example. Please seek further
assistance if you are concerned.
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What this model will not do
- This model does not calculate heat
flux to the roof. Therefore, the
slider bar changes color when a tree
abuts or overhangs the roof. In
general, fire planners seek to keep
trees 10 feet or more away from
structures and further from
chimneys. Single unmaintained trees
that overhang a structure pose a
moderate threat, as wildfire can
spread from the tree crown to the
home. However, this fire hazard can
be significantly reduced by raising
the crown and thinning the canopy.
Multiple trees pose more complex
interactions, as each adds to fuel
loading.
- This model does not account
for fire weather or severe slope.
The model simulates thermal ignition
only. Effects of winds and burning
embers lofted by a crown fire have
not been included in the model.
During extreme fire weather (hot,
dry and windy conditions) nearly as
many homes are lost to embers as
they are to direct thermal ignition
from flames. In addition to
developing and maintaining fuel
treatment zones, it is highly
important to build non-combustible
structures, protect vents from
embers and to install dual pane or
tempered glass windows.
- The building construction
material feature has not been
programmed for different building
materials. This initial version was
modeled for typical home
construction. Building or
retrofitting structures for fire
safety is a critical step in
protecting property from wildfire.
- Fire spread from grass to
shrubs to trees is not modeled. In
reality, ground fuels can influence
fire spread and behavior. Fires
generally start in a receptive fuel
such as grass, and spread to larger
plants that overtop them through
ladder fuels. Maintaining separation
between grasses, shrubs, and trees,
reduces fire hazard. For example,
the separation distance between the
top of shrubs and the bottom of tree
crowns should be greater than two
times the shrubs’ height.
- The hazard posed by off-site
structures, fences, wood piles, and
trees are not included. When on-site
fuel treatments alone fail to
mitigate a fire hazard, off-site
fuel treatment is needed.
- The ability to prune a tree to
remove deadwood and thin the crown
is not provided. The driving force
in fire behavior is the fine fuel,
stems less than ¼-inch in diameter
and foliage; these fine fuels carry
the fire. Fuels larger than 1/4-inch
contribute to fire intensity, but
not necessarily to fire spread.
Routine tree care to keep trees
healthy and pruning to remove
deadwood is critical to reducing
fire hazard.
- Ignition characteristics of
different tree species and their
fuel moisture values are omitted
from the model. Little empirical
data exist on the fire behavior of
specific species, but it is
available in other formats. Many
fire departments have lists of
species to exclude from fuel
treatment zones due to their
flammability. The UC Forest Products
Lab list contains many species that
pose hazards. The site is located at
http://www.ucfpl.ucop.edu/I-Zone/XIV/vegetati.htm#Unfavorable
Plants.
- The model calculates radiation
emitted from individual trees, and
does not reflect synergistic effects
of tree massings. Generally, a
single specimen size tree when
properly maintained (canopy raised,
thinned of deadwood and meeting ANSI
A300-1995 – Standard For Tree Care
Operations, Tree, Shrub, And Other
Woody Plant Maintenance) poses
little hazard. However, when trees
or shrubs are grouped, fire dynamics
increase their heat flux more than
their cumulative individual effect.
The farther individual tree crowns
are separated from one another, the
less likely it is for an individual
tree to burn. Generally, 20-feet of
separation between mature tree
canopies is recommended to eliminate
crown fires.
- Under Buildings, the deck
feature has not yet been programmed
to influence fire behavior. The pool
feature is for use with the
ecoSmart-Water component.
- Under Add Landscaping, the
tall grass, rock, bare dirt, and
shrubs features have not been
programmed to influence fire
behavior.
- The window and roof features
are inoperative.
- Under Add BMPs, the cistern,
drywells and swales features are for
use with the ecoSmart-Water component.
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What about buttons that don’t
work?
In addition to the limitations
listed in
What this model will not
do, this first version has not been
completely programmed to provide
access to all of the features. The
following buttons have not been
programmed to function.
- Buildings/construction
- Buildings/walls
- Buildings/roof
- Buildings/window
- BMPs/pruning
- BMPs/crown reduction
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Menu Options
LOT
- Location – Currently
set for Lake Tahoe
- Description
– Provides a summary of your
selections for your lot properties:
shape, length, width, slope,
groundcover, and grid.
- Weather/climate – Currently set for
Lake Tahoe
- Orientation – Allows you
to set the compass-direction your
lot faces.
- Soil – Inoperative for
ecoSmart-Fire. Will be activated for
ecoSmart-Water.
- Pavement – Allows you to
create rectangular-sized sections of
pavement to be placed on your lot.
BUILDINGS
- Add wing – Allows you
to create rectangular-sized wings of
your home, garage or out-buildings
to be placed on your lot. Note: The
main portion of you home is also
considered a wing. Selections
include: length, width, number of
stories, and air conditioned.
- Add
window – Inoperative for
ecoSmart-Fire.
Will be activated for ecoSmart-Energy.
- Add deck – Allows you to create
rectangular-sized sections of deck
to be placed on your lot.
- Construction – Inoperative for
ecoSmart-Fire. Will be activated for
ecoSmart-Energy.
- Walls – Inoperative
for ecoSmart-Fire. Will be activated for
ecoSmart-Energy.
- Roof – Currently
inoperative
ADD LANDSCAPING
- Pavement – Allows
you to create rectangular-sized
sections of pavement to be placed on
your lot.
- Lawn – Will automatically
appear over your entire lot. You
will need to add additional features
to reduce the size of the lawn area.
- Tall grass – Allows you to create
rectangular-sized sections of tall
grass to be placed on your lot. Tall
grass is considered grass that is
not regularly mowed.
- Rock – Allows you to create
rectangular-sized sections of rock
cover to be placed on your lot. Rock
is considered significant areas of
naturally occurring rock outcrops or
artificially placed rock and gravel.
- Bare dirt – Allows you to create
rectangular-sized sections of bare
dirt to be placed on your lot.
- Pool – Allows you to create a
rectangular-sized pool to be placed
on your lot.
- Trees – Allows you to
select your trees from a list of
species and then chose one of two
options to further define your trees
– age or dbh. Dbh is defined as
diameter of the tree at breast
height or 4 ½ feet above ground. If
you chose age, the program will
automatically calculate dbh, height,
crown diameter, crown height. Water
usage will be set to medium. If you
chose dbh, the program will
automatically calculate age, height,
crown diameter, crown height. Water
usage will be set to medium. If you
select the advanced option you can
manually set height, crown,
diameter, crown height, and water
use for each of your trees.
- Shrubs – Allows you to create
rectangular-sized shrub masses to be
placed on your lot.
ADD BMPs
- Cisterns – Inoperative
for ecoSmart-Fire. Will be activated for
ecoSmart-Water.
- Dry well – Inoperative
for ecoSmart-Fire. Will be activated for
ecoSmart-Water.
- Swale – Inoperative for
ecoSmart-Fire. Will be activated for
ecoSmart-Water.
- Trees – Same choices as
Trees under ADD LANDSCAPING
- Pruning – Currently inoperative
- Crown raising - Allows you to simulate
raising the bottom of tree crowns to
see the effect on fire danger. Two
selections need to be made: 1. the
height to which you want to raise
the bottom of the crowns, and 2. the
distance from your home that all
trees will have their crowns raised.
- Crown reduction – Currently
inoperative
TOOLS
- Move reference point
– Allows you to move the north arrow,
or reference point, to a spot more
convenient on your lot. By selecting
Show distance to reference point you
will be able to easily determine
distances to various objects on your
lot.
- Orientation – Allows you to set
the compass-direction your lot
faces.
- Add dimension line – Provides
a ruler for easy reference.
- Add
text – Allows you to add words to your
lot.
- Show distance to reference
point – Provides distances on x and y
coordinates from the reference
point.
- Show legend – Will display
all items, along with the number of
each item, that you have been placed
on your lot.
VIEW
- Hide orientation
- Hide
pavement
- Hide pool
- Hide rock
- Hide lawn
- Hide tall grass
- Hide
bare dirt
- Hide trees
- Hide shrubs
- Hide BMPs
- Hide grid
- Hide
dimensions
HELP
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