good afternoon everyone and good morning
to those on the west coast
we will start this soul smart virtual
training
in about a minute or so thanks for your
patience
i just killed the attending window good
job
[Music]
okay
all right we'll get started here hello
and welcome to today's soul smart
virtual training my name is nick hazza
and i'm a program manager
focusing on energy and sustainability
with the national league of cities
today is the first in a three-part
training series on best practices for
solar pv permitting and inspection
today's session will focus on simplified
solar permitting
before we get started with the
presentations
i'd like to review some webinar training
details
to make sure my slide advance is here
correctly
um everyone is on mute and will be
throughout the session
the training is being recorded and we
will
have the recordings available online
after the training
we will also have a follow-up email that
will share
the slide deck as well if you do have
questions please submit them to the
organizer
through the question feature and go to
webinar
or if that's not working for you you can
email me
at paza nlc.org
we'll try and address questions as they
come up
with the slides or we'll leave about
five to ten minutes at the end
to address some questions as well
so here's a quick look at today's agenda
i'm going to do a very brief
introduction of the soul smart program
we will then
hear about soul smart's partnership with
virginia's department of mines minerals
minerals and
energy and the virginia solar initiative
of uva's weldon cooper center for public
service
we will then get to the real fun
materials bill brooks a principal from
brooks engineering will present
simplified solar permitting
this training is brought to you by
soulsmart a national designation and
technical assistance program for local
governments
funded by the u.s department of energy
the so-smart program provides assistance
to local governments to enhance their
solar markets
making it easier and more affordable for
homes and businesses to install
or access solar energy i will now turn
it over to
carrie hearn from dmme and elizabeth
marshall
from uva to briefly discuss
why soulsmart partnered with their
respective organizations in virginia
hello everyone and welcome and thank you
for taking time out of your day to
attend this training and hopefully
everyone will also be back for the next
two in this series
uh my name is carrie hearn i'm the solar
program manager at the department of
mines minerals and energy
and um i've been in this position since
september of 2020
2019 and the position was really created
to support localities
to invest in solar and to
create the mechanisms for individuals
and businesses
in the community to do the same and so
through this role we've identified
opportunities through
soul smart to bring additional no cost
technical assistance to localities
and we
identified a number of uh shared goals
with the virginia solar initiative
at uva um in terms of their goals um for
their program and so we decided to
partner together
and become
soul smart advisors for the state
and so we're pleased to be offering so
smart
in this partnership between the solar
foundation and its partners
dmme and uva and so earlier this spring
we launched the program and we've been
working with
individual localities across the state
to
really understand what are the
challenges and opportunities
for solar development in their uh region
and so we really appreciate all of the
consultation conversations that we've
had to date with a number of you
or your colleagues who may or may not be
on the phone
and we're really focusing in
on three areas across virginia that
include
the middle peninsula the south side
region of virginia as well as southwest
and want to recognize the existing
soul-smart designated communities that
include
those eight localities in southwest but
also others across the state
in northern virginia in places like
charlottesville and richmond
and beyond and so um all of this work
that we're doing today
and that you're doing in your
communities will help the state
reach our 100 clean energy goals
that have really been cemented through
the virginia clean economy act
and as well what was set forth by
governor northam's
executive 43. so with that
i'm very pleased to be here and to hear
your questions at the end
i'm going to turn it over to elizabeth
marshall from uva
thank you
great thanks carrie hello everyone
welcome i'm so glad you could take the
time to join us today
i think carrie gave a really great
description of
our partnership and mentioned our shared
um goals and values related to
helping the state expand its so the
adoption of solar
at the distributed at the utility scales
as well and so
i'm the coordinator of the virginia
solar initiative at the weldon cooper
center for public service at uva and as
such our focus is to help support
localities
as they're developing and adopting
policies and procedures related to solar
development and so that includes
um looking at permitting and inspection
processes
as well as other things like planning
and zoning policies um utility
engagement and other
other categories that the soul smart
program covers
so we're really excited that you joined
us today and that we have the
opportunity to
present this three-part training to you
um i echo
carrie and saying if you're interested
in learning more about soul smart
and joining up with us for this year's
cohort that we're developing
to please visit the dmme uh soulsmart
website and
fill out a request for consultation form
so thank you very much
and nick all right thank you
both to carrie and elizabeth and now as
promised we will get
to the really good stuff and i'm going
to
make bill brooks the presenter and i've
worked with bill on soul smart for
probably the last
four years or so he is just an absolute
expert when it comes to solar permitting
the way i like to say that he's
written quite a few uh solar guide books
including one in california to really
outline
best practices for solar permitting and
inspection so we are in very good hands
with bill today as he leads us through
simplified solar permitting guidelines
all yours bill thanks nick
uh can you hear me yep i can hear you
great we just want to make sure we're
we're good and uh
thanks everybody good afternoon for
those of you who are
on uh time zones
on the east coast in central um
but uh today we're just gonna do a short
session we're gonna focus on
uh get getting started with the
guidelines and
uh talk specifically about structural
aspects of those and then next time
we'll talk uh more maybe finish out some
structural things if we don't finish it
all today and then talk about the
electrical
part of the guidelines and then the
third session will be focused on
inspections
interesting we're talking about virginia
i started my career at nc
state university acc school
so we've got a lot of acc folks i'm sure
represented on the call and uh
i'm sorry if you don't like nc state but
that's that's life
and uh but uh yeah
we've got a lot of good ties there i
worked with dmma uh
25 years ago so uh i've worked
with these organizations for a very long
time
been in this in my career in
solar photovoltaics for grid connected
pv
for 32 years there's only
a couple of dozen people in the world
that can say that
and so that's i'm proud of that uh
i was a kid when i started of course i
was 12 and so um
you know now i'm in my mid-30s when i
when i think of myself
but let's get into some of the material
and i'll try to flip-flop around on my
screens here
uh we're gonna be talking about
permitting today and the guidelines
this is an old map but it tells you you
know
the soul smart communities are all over
the place um
this is the current map if this comes up
correctly hopefully it does
and you can go to the soulsmart website
we want to encourage you to do that
um there's a lot of great materials on
the soulsmart website
this is just part of the process
providing these webinars
and uh also want to focus you on the
soulsmart.org
um forward slash permitting website
which is the one that we're going to be
talking about today so all the resources
that you're taught
you're you're going to hear about today
if you go to this website here's the
main
main page and you can look through the
steps and the resources and there's pdfs
that you can download
there's also webinars uh
here that you can uh view as well
so all these resources are there and
really want to make you
aware of these things um
because you're why they're there so
let's see
uh let's go back to our
um slides and and talk about why do we
have permitting guidelines why
what's the need for that uh i've been
working on permitting guidelines since
oh probably 2000 2001
when um the city of san diego came to me
and said
can't we just come up with something
that's uh kind of
simplified like we do for air
conditioners and things like that
and i said well you know it's kind of a
little more complicated maybe but
i guess it's kind of similar so let's
let's work on it let's see what we do so
um work with the gentleman there um
and we were able to put together some
things and then
further down the road uh we put together
the expedited permit process for the u.s
department of energy
which which has been used in a lot of
different scenarios and then on
the california guidelines were
established
through a law actually 2188 in
california
and so all the jurisdictions were
somewhat heavy-handedly
encouraged to use a permitting guideline
and then when soul smart got going uh
certainly one of
one of the important aspects of getting
more solar into a community is to have
some some structured guidelines to make
it simpler
for the jurisdiction to review
and to approve permit applications
uh on on stuff that they're just not
that familiar with
now certainly over time as you get more
and more solar in your communities
um you might have some folks that are
very very uh
involved and well informed about these
things but uh it's nice to have a
structure it's nice to have something
where
people with a lot of experience have
gone through the details of it
i've done it many times and come up with
materials that
primarily for simple pv system
installations
where only a basic basic review is
necessary
so it's focused on residential and we'll
cover
a good portion of residential
applications some of these some
residentials can get very complicated
and beyond the scope of this for sure
but it also could cover some small
commercial a lot of our small commercial
installations are very similar to
residential installations in fact the
the services may be
identical to a residential
installation and so then we also have
building code
as well as fire code and uh in addition
to the electrical code requirements
that these things are intended to uh
address
okay so kind of the way it's laid out
is um there's an eligibility list
essentially defines the details of
what's in these things uh
what kind of information needs to be
supplied
um what structural review is required
to do and what the electrical review is
required to cover and so
we're going to go into those things and
kind of walk through
in detail an example
and we're going to use a virginia site
in our examples
one thing that's important for a lot of
jurisdictions to understand is that
when they see something like this there
might be the concern that is this
is this kind of extra biblical is this
like beyond the scope of the
of our codes all that kind of stuff and
um this is not intended to create
explicitly or implicitly any new
requirements it's really
saying if you follow these rules they
are going to be
they're going to focus on things that
are in compliance with the codes that
are relevant mostly the
residential and the electrical codes are
the ones that are the most relevant
at this point in the game and it's going
to focus on those and that
if you follow these guidelines you'll be
in compliance with those codes
now some of the stuff will be more
restrictive than the codes
part of that is due to the fact that
we're trying to simplify the process
and part of simplifying the process is
defining what i call a box
where we we define the parameters
of what the pv systems are that would be
allowed to go through the simplified
process
it doesn't mean that you couldn't do a
more complicated system just a more
complicated system would not
go through this simplified process but
if we can cover
80 percent maybe more than that
of the systems that are out there then
um then we really accomplish something i
think and can help lessen the
the burden on communities and uh
also help contractors understand what's
what's
expected of them that's really important
as well
so we're going to talk about a permit
application so there's the basic
information
you know most communities are going to
require some type of permit application
of course that's going to talk about
the project scope the location who's the
installer
all that kind of stuff whatever things
that are and those are typically
jurisdictional jurisdictionally specific
because each jurisdiction may have some
special items that they require in their
communities as far as part of
a permit package a lot of permits as
everyone knows
due to covet have gone online a lot of
communities had already been moving in
that direction and were kind of pushed
over the edge
um and so part of this whole process
is to say listen this is intended to be
set up as an online process
and so if you're looking for things that
can help you with an online process here
we are
we're from the government we're here to
help um well we're government funded and
we're here to help
so uh let's talk about
some of the other items in the in the uh
permit package
typically we're gonna have some type of
a site plan the site plan is gonna show
the major components where they are on
the property
you know it may not be exactly the scale
but you know a roof
roof layout where the solar panels are
making sure
uh if there's any uh setback
requirements
required uh in the now in the
residential
uh fire code or the residential code
fire setbacks
any other things like that we're going
to have in that site plan
next slide we're going to be talking
about the
we also have the structural and
electrical worksheets which go through
the details of what's in the picture
what's what's in the project
uh how the structural aspects are being
addressed how the electrical aspects are
being addressed and then any
specification sheets
and installation manuals that might be
required as part of the process
so again as part of the what's the
purpose of the simplified process
um consolidating the electrical and
structural and fire review
into one review and residential projects
if it has to go to multiple departments
that certainly slows the whole process
down it makes it more expensive for
everybody
and of course permit fees are going to
have to be higher just because the fact
that
multiple jurisdictions are touching that
now
permit fees can always be an issue and
we don't really get into the details of
permit fees but
that's always a discussion of trying to
keep the permit fees
in check keep keep them in line with
what's actually
uh the effort level involved and then
make sure that we streamline the process
so that the jurisdiction isn't
isn't essentially losing money by
reviewing these so if they can review
them quickly and make sure everything's
in order
and the more of that that can be done
automatically the better
we want to eliminate the need for
detailed engineering studies
because that often uh causes delays and
so
the reason we have a
code book in the first place both
electrical and building code the reason
we have these codes is because we're
taking engineering
and we're boiling it down and we're
giving simplified
uh kind of layout because if you follow
these rules
you are following the physics and the
engineering of what needs to happen
conservatively absolutely um
but if you follow this you're good if
you want to specifically engineer
something because it's unique and
different
then you're going to have to hire an
engineer and you know we're going to go
through that process so this is
we're eliminating those things we're
saying here's you follow these things
you're
you're uh we're not circumventing the
engineering process we're just saying
this
meets the requirements and you're within
the engineering
requirements that need to happen whether
it be structural electrical
also making sure that you're clearly
compliant with the electrical and
building codes
so this box that i mentioned
there's a few items that we're going to
focus on so the box is saying that we're
no larger than about 15 kilowatts which
is a pretty large system but
system sizes have been growing over the
years the solar's gotten a lot cheaper
so uh 15 kilowatt system be a very large
system
by the way i have like 35 kilowatts on
my house don't ask why
i'm just weird um i've got four
different
battery based systems on my house i've
got
you know so i'm just a little crazy
don't worry about me
most systems are going to be in the five
to seven kilowatt range
um we're also focused on one and two
family dwellings or structures of the
same construction so the
building code says that if if a building
is constructed
as a one and two family dwelling that
you can
apply the rules of one and two family
dwelling if you so choose to
uh it's not a requirement it's it's
given up it's up to the jurisdiction to
do that
but one or two family dwellings there's
a lot of consistencies in how one and
two family dwellings
are constructed certainly in the
um i would say typical one and two
family dwellings
of course we can have one family
dwellings as you know
certainly in virginia and in california
we have ten thousand fifteen thousand
square foot homes that's really not
a dwelling that's a castle um we're not
really gonna be focusing on those things
and i'm pretty sure those folks can hire
engineers those poor
poor people but we're not going to worry
about them
uh string string inverters dc converters
micro inverters these are different
types
of electronics that are used we're going
to show different uh aspects of that
when we get the electrical part
and then we have this eligibility
checklist
so the basic rules uh we're focused on
covers the vast majority of the united
states including virginia
um where our snow loads are no greater
than 60 miles per hour
60 pounds per square foot and our snow
and our wind loads are no greater than
150 miles per hour so we'll see some
maps on that
and see how virginia comes in okay so it
turns out
that the little red line is the 150 mile
per hour
line and this is based on the current
building codes
and we see that the gulf coast the
southern third of florida
the outer banks of south carolina and
maybe the edge of north carolina
and martha's vineyard are above 150
miles per hour
uh the entire state of virginia as we
know it
is within the 150 mile per hour
number um now you could have a locale
that states a higher number
and i'm not gonna argue with them
whether it's true or not
these are just the general maps and
locales can do whatever they want
the 60 pound per square foot snow load
line
covers everything in the united states
with the exception of northern vermont
new hampshire maine and the upper
peninsula of michigan
and a little tiny bit of minnesota so
unless you live in those places
we're okay as well so so the basic
guidelines will work in that we've
actually done guidelines for those
little
places in these these places that exceed
60 pounds per square foot 150 miles per
hour
but we usually don't have to talk to the
talk about that when unless we're doing
uh you know a gulf coast or florida
application something like that
now there's other things like wind case
studies and all uh
in the mountains in the rocky mountains
and the sierras we have some special
case studies
again we don't have a lot of folks
online that are worried about that
there's all kinds of
of snow loading case studies and high
elevations and things like that on
on the western half of the united states
but that's just to show that those
things do exist
we also have wind case studies in
western north carolina the appalachian
chain
and uh the northern part of the
appalachian chain
we know you've heard of places like
mount washington very very unique wind
loading situations that are dramatic
and so again there are very
site-specific wind loading concerns and
snow loading concerns where there's
higher elevations higher winds
um generally not a lot of people living
in those places but
uh those locales certainly know who they
are
okay um so for member attached
so we're going to talk about a couple of
different types of attachment methods so
solar panels
we're attaching them to rooftops we're
focused on rooftop applications in this
if we have a ground mount application
nothing wrong with ground mount in fact
every system that i've done for myself
personally a hundred percent of them are
ground mounted
um and so because i personally don't
like putting stuff on the roof of my
house it's just a weird thing i have
so i've got literally 35 kilowatts of
ground mounted pv
which is really cool um but i've also
worked with a lot of friends and
in most of the systems on my friends
houses are rooftop
so rooftop applications tend to be
simpler easier it's a great place to put
solar panels as long as you do it right
um and it also helps with things like
shading and stuff like that you get it
higher up off the ground you have less
problem with trees all those kinds of
things
are helpful so again 60 pounds per
square foot 150 miles per hour
those are basic things when we say we
say something is member attached it
means that we're actually
screwing the attachments into the
structural members
of the roof so it's either going to be a
manufactured truss or it's going to be a
rafter construction
either one we're going to be struck
we're going to be
screwing typically anywhere between
quarter inch to 5 16
lag screws uh into those
members structural members to physically
attach it to the structure and the
structure is going to transfer that load
through all of its attachments to the
foundation
of the house so if the house is not
properly built
if it's not built to code if it's
haphazardly built
then there might be a question of
whether or not it's structurally sound
if it's built to code and it's all been
attached correctly and
attached to the foundation correctly
we're not going to blow away
regardless of the wind speed because
it's been designed for the wind speed of
the location
um we're not going to allow anything in
this
again in simplified guidelines we're
going to eliminate exposure d which is
waterfront where we have a
miles worth of waterfront in front of us
now anywhere
in virginia and in the delmarva
region uh by the way i grew up in the
delmarva region
i i spent my summers on the eastern
shore of maryland
sailing crabbing fishing you know
all that kind of stuff i was a i was a
bum
uh in the summer times growing up it was
a great place to grow up love it
um my grandparents lived on the
waterfront but their waterfront
was about a quarter of a mile
across so it would still not be exposure
d it'd be exposure c
uh exposure d is uh is your waterfront
maybe um well you've got uh
a good example but might be uh george
washington's house okay
so he's up on a hill he's looking over
the water maybe that's exposure d
um things like that but uh waterfront on
the ocean for sure is exposure d
large lakes exposure d not on a steep
hill five percent grade
so mount vernon is also kind of
uh got a pretty steep escarpment coming
up there from the potomac so
uh yeah that would also kind of be a
problem
and so george washington's gonna have to
hire an engineer
but um that's okay george was president
he was a he was a smart guy
he might have engineered it himself he
was you know right he was a surveyor
right i
i actually visited one of the places and
had
his initials carved into the rock that
was really cool
um the roof mean height uh 40
40 feet or less so again this is for
houses that are not
10 000 square feet and 60 feet tall or
anything like that
um even mount vernon i don't think is 40
feet tall
it's very picturesque but it's not 40
feet tall
so roof mean height means the actual
peak of the roof might be 45 feet
and then the roof structure meets the
irc i don't know whether specifically
mount vernon meets the irc
but it's it stood the test of time for a
couple hundred years
i don't think we're worried about that
structure and that there's no structural
damage so structural damage obviously
can happen when you have roof leaks
things like that or structural damage
can happen because
somebody actually damages the structure
by removing
structural elements from the roof this
this happens occasionally
i don't think it happens all that often
but um there's a lot of folks that maybe
want to use their attic as
as storage and they get up in their
attic and they've got all these two by
four
truss um struts in their way and they go
man i just can't fit my
my christmas stuff up here so uh they
got a skill saw for christmas and
they're what i don't have anything to
cut well now i have something to cut
so they take their skill saw and and
they trim out some
two by fours burn them in their
fireplace because that's the only wood
they've ever had
and um and now they've got room to put
their their christmas stuff
well you you've radically changed the
structural
uh aspects of that and all of a sudden
you know all these presuppositions just
don't hold water so to speak
well the roof probably won't hold water
for very long after that
so with a member touch system first of
all we
we start with the first item on our list
is the array is set back from all the
roof edges
and ridge by at least twice the gap
under the modules
or more if there's a fire access pathway
required it could be quite a bit more
than that but this is a wind loading
issue and what it says is that
a typical array if you're not familiar
with them
they're typically mounted about five
inches the
bottom of the modules are about five
inches off the roof deck
all right and so what it's saying is
that if you're five inches off the roof
deck you want to be about 10 inches
away from the edge of the roof the
reason for that is they've learned over
the last 10 to 15 years
that there's some high pressure vortexes
related to solar panel
there's some high tech pressure vortexes
right at the edge of the roof
and if you capture those with the edge
of the panels you can actually have some
very intense loads
that exceed the ratings of the modules
even and so
by stepping back a little bit away from
the edge you get away from that high
pressure vortex and like i said if
you've already got a requirement for a
pathway
you may be fine in that one area but
there's going to be places where you
don't have a requirement for
an access pathway and therefore you need
to pay attention with
being away from the edge of the roof it
looks better anyway um
we certainly don't want to go over the
edge of the roof we don't want to go
over the ridge of the roof so it has to
stay in the plan view
of the building and this is even more
constraining than that gotta move back
from the edge of the roof
also we don't want to cantilever over
the perimeter anchors and we'll see a
diagram of this in a minute
more than 19 inches what that means is
that we typically put
attachments on the roof and we we mount
a rail on top of that
the rail then is actually what the solar
panels are
attached to but the but the rail
the anchors for the rail and the roof
are obviously what connected to the
building
now the perimeter anchors that are
connected to that rail around the edges
are the ones that are going to very
logically
um and intuitively get the most load
because they don't get they don't get
any help from anybody else they're all
by themselves
they also are the are the anchors that
are the most heavily loaded
whether it be for snow loading or wind
loading so
the perimeter of a system always gets
the most loading and so
when when we're doing when there were
literally thousands
of simulations done to come up with
these guidelines
and so in the process of that we set
these parameters in play
because we gotta say we gotta we gotta
uh define
where we stop in all this and so if
you're gonna go over more than eight 19
inches on a perimeter anchor
you need to go on to the next rafter and
attach to the next rafter
and then you don't have a cantilever at
all in that case
but that's just an allowable cantilever
it's commonly done
it it makes it look more aesthetic if
you can kind of cantilever the panel
over the end uh uh anchors because then
it hides the anchors and stuff like that
so the gap under the modules we want to
keep to no greater than 10 inches so
that's why we're never
we're never going to go over the ridge
of the building
we're not going to tilt up more than 10
inches off the roof deck
things like that so if we had a flat
roof construction
we might tilt up a little bit just to
allow dirt and
and dust and things like that to wash
off in the rain
uh but not more than 10 inches and this
has to do with how much wind are we
going to capture behind
this large sail that we're putting on
somebody's roof so we want to
we want to do that now this large sail
we're putting on the roof has some
advantages
um in that it keeps the sun off of the
attic
and cools the house down and and also
keeps the sun damage off
of the shingles and whatever roofing
systems you have so there are some real
advantages to it but we also want to
make it clear that
we're aware of the structural loading
going on here
one thing that's been added to the
building code is that
it requires that there be a gap between
modules a quarter inch on the long and
short sides of the modules
now this is very common in most
installations most fastening methods
have a fastener that goes down in
between the solar panels
and that creates at least a quarter of
an inch gap and sometimes up to an inch
gap
these these gaps that we're talking
about here are for
pressure release so
you might decide that you want to build
a kite
and you decide to put pretty gaps
so the sunlight comes through every uh
five inches
well that that kite's not going to work
very well because you're allowing a
pressure release you're allowing the air
to flow through it it's not going to
fly like it should you make it solid you
make it continuous
and then the kite flies quite nicely so
in this case we're trying to make
a kite that doesn't fly very well and
that's why we have these gaps in between
the panels and an alternative to the
quarter inch on all sides might be
we could butt the short sides of the
panel since most panels are rectangular
in shape and we can butt the short sides
together and we could leave a half an
inch gap on the long side
and that would be better than even
quarter inch all the way around so
just giving a couple of options on how
to do that
all right we'll go for about another ten
eight minutes
and then we'll open it up for questions
so if you're if things are coming up in
your brain
like what in the world are we doing here
um we can go back to any of these slides
and talk about it in the time we have at
the end here
the mounting rail orientation now we
don't always use rails there are there
are what we call
rail less
mounting systems they'll use the anchors
and the modules together
uh without continuous rails they might
actually have short sections of rails on
some of these rail list
systems but in general the re if we got
a rail system which is by far the most
common
we're going to run those rails
perpendicular to the rafters or trusses
so if you look at a house from the front
you know the rafters or trusses are
going from
the eve to the ridge and in a parallel
fashion hopefully
um and then our rails are going to go
crossways
across that and they're going to cross
the rafters which allows us to attach
with to whichever rafters we need to
in order to spread the load out and
attach to the structure
so that's the basic approach and then
um if we're talking about spacing
perpendicular to the rafters we're
generally if we're in this
60 pound per square foot 150 mile per
hour wind regime
all we have to know is that we don't
want to exceed four feet on center
and the anchors in the adjacent rows we
need to stagger
and we're going to show you what that
means it means that every other row of
rails is going to be attached to a
different set of rafters and that what
that does is that spreads the load
evenly among all the rafters
and gives us a perfectly even loading
of the roofing system and it also allows
each truss or rafter to participate in
the process
of holding the solar panels down we want
to keep everyone together
and working together as friends
and we're talking about typically 24
inch on center or less
construction that's standard
construction we do have constructions
around the country
32 inch on center some even four foot on
center
and in those specific applications we
need some other things
to come to to figure out whether we
typically have to be in low snow load
and low wind load areas to actually
attach to those systems effectively
and or special engineering so what we're
saying here is that this is very
conservative engineering that went into
this stuff
and that doesn't mean that somebody's
got a 32 inch on center roof can't do
solar
that's not true at all it just may mean
that
an engineer is going to have to go
through it make sure that the structure
is sound
make sure that the attachment methods
are correct and all that kind of stuff
and we're saying that if you follow
these rules on 24 inch
or shorter span spacing
systems for roof roofing systems you're
going to be good to go
no problems all right the upslope down
slope spacing
on your on your rails so the rail
systems
you typically have two maybe even three
rails that hold the panels down
um that are going cross across the
rafters or trusses on the roof but the
distance between those rails
upslope and down slope is not set by the
by the rail manufacturer that's set by
the module manufacturer
so the module manufacturer let's say for
for a typical is about a little over
five feet tall
okay so it's five feet tall and um
you're typically going to see that the
installation instructions tell you to
mount about a foot in from either end
of the short end of the module okay so
so your rails are going to end up about
roughly three feet apart
so five foot module rails are three feet
apart that gives the best loading of the
module
most even loading for structural of the
module
and and transferring that load onto the
roof
and not over stressing the module
whether it be snow load or wind low
the fasteners in number eight are going
to typically be
either 5 16 lag screw with two and a
half inch embedment which means we got
about a four
inch screw four inch screw to go through
the mounting bracket through the roofing
material through the decking
and then finally making it to the
structural member
and fully embedded in the structural
member two and a half inches
that is standard construction
you put 20 of these on a roof you can
literally lift the house with it
if the house is attached properly you
could take a crane hook it to those 20
points
and literally lift the house right off
of its foundation pick it up move it
wherever you want it
enormous amount of holding power in
those things
all right the other method option b
would be some method that the
manufacturer's instructions cover
which go through a similar um
loading characteristic it could be
double quarter inch fasteners three
inches apart
there's a variety of manufacturers
methods that have that have come along
that work well work equally as well
but they're engineered and they have the
engineering to back it up
okay so some of the structural takes
takeaways on
on on this member mounted systems uh is
that houses
that are built to the code can support
pv that's a basic
straight up if it's built according to
the code it's going to be
sufficient if you also we're focusing on
a single layer of roofing
because we also have some extra
live load capabilities in a house that
doesn't have a second layer
of comp shingle i'm not a big fan of
comp shingle
extra layers personally especially if
we're trying to attach
solar panels and flash uh you know
attachments or flash anchors and stuff
like that
so it's another reason why we kind of
shy away from those things
generally have better success if we
start with a single layer of roofing
which in many cases might require that
the customer
do a tear off of their existing roofing
system
think about the fact that you're going
to put something on that's going to last
20 years it's also going to make the
roofing
last longer and so you really want to
start with a fairly recent roof if not a
new roof anyway
so it also lightens the load on the roof
things like that
again we're going to mount modules are
going to be mounted typically between 2
and 10 inches off the roof
uh the roof or rate distributed weight
all systems that i'm aware of today
are less than 4 pounds per square foot
but that was part of
uh the design guidelines that we put
together can't have a system that's
heavier than four pounds per square foot
typical numbers when i do calculations
on systems today between two and two and
a half pounds per square foot so we're
almost half that
limit and then with typical rafter
supports 48 inches apart or closer
um our we can mount our
our roofing systems our our anchoring
systems
and we if our alternating rows
are on alternate rafters we can go all
the way up to 60 pounds per square foot
and all the way up to 150 miles per hour
and have no problem with structural
requirements
now what i'll i'll just leave you with
is that we also came up with
options for low snow and low wind
loading conditions
and it's kind of funny virginia kind of
catches the edge of these things
in southern virginia and part of north
carolina
but if you look at the yellow line the
yellow line is the 120 mile per hour
wind loading and we we clearly see that
the delmarva peninsula
doesn't really is above 120 miles per
hour certainly the
atlantic side of it uh but a good
portion of the delmarva peninsula
is is over 120 miles per hour the
norfolk region is above 120 miles per
hour
all that kind of stuff but as you move
inland
maybe towards south hill that region
around there right around the border of
north carolina
know a lot about that area because i
lived there for quite a long time
um you know we have this area where
they're
going low wind loading and um
and so you can do some some things that
you can't do other places
and so that's what's showing here
certainly we have a
southern southwest texas southern new
mexico
southern arizona and half of california
that have no snow loading requirements
at all because there's no snow load
there
the no snow load areas inside in the
gulf region unfortunately coincide with
120 mile per hour wind regime
so they really don't buy you anything
here down in the bottom
it really buys you where this green line
is or where the blue line is
inland inland uh southeast
and it it works its way into
what i would call southeastern virginia
whatever you go call it um with those
special issues our
our our mounting rails could be parallel
to the rafters instead of perpendicular
and not more than four feet apart so
sometimes folks want to run their
their rails vertically well if they're
in a low snow load won't know
low wind load area less than 10 pounds
per square foot less than 120 mile per
hour wind regime
then that would be okay and there's
probably several places in virginia
where that's true
um if we're perpendicular to the rafters
then um and we're in this low snow load
area we
we can do it orthogonally orthogonal
means in this b
it means that we don't have to go to uh
uh to spacings
staggering the spacing on on additional
on adjacent rails and we'll
we'll show you a picture of that when
we're talking in the uh
in the question period coming up here in
just a minute and then
we could actually go if you had zero
snow load and 120 mile per hour
you could actually have an orthogonal
arrangement where you're attaching to
the same rafter every third rafter on a
24 inch center
rafter system as long as it's less than
six and 12 and the ground snow load is
zero which is a lot of california and
like i said the southern united states
then you could do that
uh i don't know that it really complies
really with well with
um with what we have going on in
virginia i'm looking for my slide for
uh for a layout and i'm not seeing it
right now i'm going to go ahead and open
it up
for questions we'll talk about sheathing
attached next time i'm looking for my
diagram of of staggering
and i think it must be way down here is
this it
no that's that's orthogonal um
that's an orthogonal sheathing attack so
um
okay i'll just bring this up so people
can see it what i mean by staggering
um pull that up on the screen
and so what i'm saying here is that
here's the little dots are the
attachment points the rails are going to
run
this way across from what the these
lines these black lines are showing
the rafters or trusses and the rails are
going to be running perpendicular
and the attachments are these little
black dots it's explained in the
structural notes over here on the right
and so this rail is going to attach to
different rafters than this rail which
is attaching to different rafters than
this rail which is attaching the
different
so you get the picture um and
so now this all the rafters
in this section of the of this hip roof
are attached
to the array and evenly have
evenly loaded the array loads which the
weight of these systems
pushing down are not important it's more
about the
uplift forces uh high snow loads
certainly on weight pushing down um when
snow
and then wind uplift forces uh when we
have a lot of wins so
with that uh do we have any questions in
the chat
i haven't been really monitoring the
chat
i don't see anything can you hear me
though
i can i haven't seen any questions i've
been monitoring both the chat
and the questions feature um somebody
did compliment that
it's been very enjoyable so far so
appreciate you taking the time for us
we will give it a minute or two to see
if folks do have any questions right now
feel free to raise your hand we could
try and do
an audio q a if not send it through the
chat
send it through the question feature
we'll give it
uh probably about five minutes or so
yeah and then
go ahead while we're waiting on that um
i just want to make it clear that if you
have questions
uh they occur to you after you get off
this there's a lot of material we're
kind of throwing a bunch of stuff
at you here and it's like i've never
seen this stuff before i don't even know
what you're talking about
um you may not be a structural person to
start with and maybe you want to share
it with your structural people in your
your community something like that
because
you know structural people are always
very hesitant to accept anything that
they didn't do themselves
and so there's a lot of great science
here
but it's all needs to be explained and
we have a permitting
uh the permitting guideline has
um information about uh explaining
what we're talking about how did we get
these numbers where did they come from
because
a typical structural person is just
going to say this is hui i don't know
what the heck these people are saying
uh you know where are your calculations
well
we have a 60 page document on the
structural calculations that went into
this
which should satisfy most of the most
anal
uh structural engineers but uh we want
to make sure that they're comfortable
with what we're doing
explain what we're doing because the
reason this stuff
is so rigorous is because we have had a
lot of pushback from the structural
community quite frankly
and um they're like hey guys um i
you know intuitively may think that
there's not a big deal here but
um i that's not how i operate i operate
off of numbers
i operate off of uh you know
calculations not off of gut and so i get
that
and that's very true so so this
information the documentation you may
not be the structural person in your
community
but you may know that person and can
forward that information to them and
that website i showed you at the
beginning
from the soul smart website forward
slash permitting
is the website you're going to want to
go to uh and download
the guidelines and the they call it
structural commentary and electrical
commentary so you go
get those documents and email them over
to your structural person
um if they're having trouble sleeping
great cure for insomnia
and they can do it
hey bill i do have um a question
just about structural does a house built
in the 70s or pre-70s have the same
structural soundness as a house built
say
post 2000 it's a really good question
um it really and i
have been doing this for a long time and
so when i started thousands in the 70s
weren't that all that old
but we started enforcing our our
structural codes a lot more stringently
somewhere between the 60s and 70s across
the united states and it was not
like all of a sudden you know on january
1
of 1971 that you could say that
everything after that was good and
everything before that was bad
uh it was it was a you know morphing
through the process of structural
uh enforcement and so really you have to
know your community
uh and i think a lot of a lot of
jurisdictions they understand their
community pretty well they know the
builders that were involved they know
that these houses were really built well
um back in the 60s or even the 50s and
these houses were kind of just thrown up
and
people had trouble with them over the
years so there's those kinds of things
when you get back in the really old
housing stocks
that were not enforced according to the
code which is a prerequisite of our
basic simplified guidelines
great question then it's really a matter
of
uh we you know looking at does it meet
the span tables
of of the uh irc
in many cases they will in some cases
they won't
we actually came up with uh guidelines
for
old construction that were based on old
growth lumber
so when you go back there's another
there's kind of a
counterbalancing thing as you go back in
the early 60s and in late
50s you actually have better lumber
so they're typically older growth um
more dense lumber and the grading of
that lumber has changed over time and so
so
you could say that there's a stronger
lumber
and you could even say that the modulus
of the lumber which is the
the width of the lumber and how that
affects
loading of the lumber we didn't do as
much planing
okay so a two by four used to be inch
and three quarters by
three and three quarters and then it
became an inch and a half by three and a
half but when did that happen that
that happened in the 60s and so then we
have rough
i i lived in a house in western north
carolina in asheville where
i grew up and um we had rough
tune full size two by fours and a half
much stronger than planed one set
one and three quarters or plain one and
a half and so
and it was old growth yellow pine very
strong lumber
um so there are some differences there
but those kinds of things may unless you
know a lot about that construction
and and your structural people are
really comfortable with it
that may be where you bring in uh you
require that an engineer look at that
older stuff the newer stuff should not
so much
and where did where was the the breaking
point where
your communities were really enforcing
the structural codes and everything was
built according to code and the span
tables are being observed and things
like that
versus older stuff that may or may not
that was fantastic thanks
for answering that one bill um i'm gonna
actually
take that control and share my screen
real quick
since i have information on uh the
two additional sessions that we have
right coming up um next thursday march
20th
so nick i'm signing off because i've got
a
another session coming up in three
minutes and so i got to prepare for that
but
if you have any questions uh please
email nick or myself
and be happy to answer them and we'll be
uh looking forward to seeing you at our
next session that nick's gonna tell you
about now
exactly thank you very much phil
fantastic thank you bill
all right so as i was mentioning we have
uh two more
sessions in this three-part series next
thursday
we will have simplified solar permitting
part two
bill alluded to it we will cover a lot
of the electrical
requirements for that session
and then we will follow it up with a
session on best practices for
field inspections and that's a little
change in our schedule that'll be
tuesday august 25th
the links i know they're quite long
right here i will
follow up with everybody with an email
with the slides that were used for this
session which will also appear
uh for the next session and this
information as well so if you haven't
registered for
session two and session three you will
be able to do that
just want to close it and thank both
terry and elizabeth
for providing the introduction if you
are interested
in small smart in virginia please
contact them please set up
a consultation call so we can get
started working with you
and we will be back next week with bill
to discuss uh the second part of
simplified solar parking
so with that i hope you all have a great
day
and a great weekend and we'll see you
next week
thank you nick thank you gary
you