DENVER GREEN ROOF INITIATIVE - WHAT YOU NEED TO KNOW MAY 1, 2018 CRA AND RCI JOINTLY - Colorado Roofing Association
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PROJECT
DENVER GREEN ROOF INITIATIVE
WHAT YOU NEED TO KNOW
DATE CLIENT
MAY 1, 2018 CRA AND RCI JOINTLY 1-K
What happened? Green Roof/Solar Basics
Today’s
History Green Roofs
Required Areas Roofing &
Agenda Exemptions
Waterproofing
and
Solar
Triggers
Permitting Requirements
Objectives Existing Buildings
Variance & cash -in-lieu
Design/Installation
Requirements
Examples What’s Next
Process
2-K
No arguing over whether or not the
Initiative is a good idea
No detailed discussion of plants
No project or system specifics
Rules of No comments about green roofs in Denver
the Day
(good or bad)
No product or manufacturer names (good
or bad)
No sales pitches!
Goal: Education about the Initiative and its
impact
3-K
WHAT HAPPENED?
DENVER'S GREEN ROOF INITIATIVE
4-KHistory - Basics
Passed (54%) in Denver on
November 7, 2017
Took effect for any permits issued
on or after January 1, 2018
Requires green roofs and/or solar
panels on a percentage of roof
areas for large buildings
Applies to: New roofs and roof
replacements on
All buildings (new and existing) which
have gross square footage of 25,000 or
more (except some residential)
All additions to buildings (except some
residential) which cause the gross square
footage of the building to exceed 25,000
5-KMYTH: The Roofing Industry
has Stopped in Denver
Roofing work
continues in all facets
of the market, including
both reroofs AND new
construction with
permits pulled after
January 1
6-KRequired Green Roof Coverage
Gross Building Green Roof Coverage
Square Footage All Other Buildings NEW Industrial Buildings *
Less than 25,000 No Requirement No Requirement
25,000 to 49,999 20% of avail. roof area Green Roof: Lesser of 25,000 SF or
10% of avail. roof area
50,000 to 99,999 30% of avail. roof area Solar Panels: 80% of avail. roof area
with a water catchment system
100,000 to 149,999 40% of avail. roof area
150,000 to 199,999 50% of avail. roof area
200,000 or more 60% of avail. roof area
* The initiative defines an industrial building as “a building or building addition exclusively used or
designed or intended for use for or in connection exclusively with the manufacturing, producing or
processing of goods, warehousing or bulk storage of goods, self-storage facility, distribution center,
truck terminal, research and development in connection with manufacturing, producing or
processing of goods.” It also includes any office space attached to what would otherwise be an
industrial building, but excludes warehouse club/retail stores.
7-KCompliance via Solar
Combinations of green roof and
solar panels can be used to meet
the required square footage, IF:
At least 30% of the required combined
area is green roof
Green roof and/or rainwater catchment
system meets requirements for rainwater
retention of .25 inches of each rainfall or
50% of annual rainfall volume falling on
the roof surfaces.
Rainwater catchment for commercial buildings
is not legal in Colorado – need variance
Existing solar arrays reduce the
available roof square footage (does
not count toward compliance)
8-KNamed Exemptions: Section D
Building Permit applications submitted prior to Jan 1st, 2018
Buildings under 25,000 square feet of gross floor area
Residential Buildings or additions to residential buildings with a height* less than or
equal to the greater of four stories or 50-feet. (no single family homes)
Commercial Greenhouses located at grade, temporary structures and air supported
structures
There is no definition in the code for a greenhouse only requirements. Does a “grow” operation
qualify as a “greenhouse”?
Implied Structural Exemption for roof replacements that will result in major
structural alterations…
* Height: the vertical distance measured between a
horizontal line drawn from the average grade to the
highest point on the building, not including specific
rooftop elements.
9-KImplied Structural Exemption:
Sub-Section 4. When an existing building or building addition
with a gross floor area of 25,000 square feet or greater requires
roof replacement the roof shall be built to include a
combination of green roof and solar energy collection in
accordance with Subsection A(2) or the maximum amount of
coverage possible so that major structural alterations are
not required. [emphasis added]
10-KWhat is a:
“Major Structural Alteration”?
From the draft Rules and Regulations:
11-KMYTH: All Existing Buildings
will be Structurally Exempt
Many low-rise and mid-rise commercial and industrial
buildings may be exempt
High rise buildings (above 15 stories) are very likely to be
able to support a green roof, especially if:
They have a concrete structure
They already have a ballasted roof
Current estimates are that 10-20% of existing roof area
in Denver subject to the initiative (not low-rise residential)
will be structurally capable of supporting a green roof
12-KWhat Triggers the
Requirements?
When you pull a permit (new construction or reroofing)
Does not apply to:
Repairs (under 10% of roof or 2 SQ)
Coatings
Recover*
* see next page
13-KRoof Replacement - Existing Buildings
When an existing building or building addition with a
gross floor area of 25,000 square feet or greater requires a
roof replacement [emphasis added] the roof shall rebuilt
to include a combination of green roof and solar energy
collection in accordance with Subsection A(2) or the
maximum amount of coverage possible so that major
alterations are not required.
14-KReplacement vs. Recover
The code is specific about replacement vs recover.
IBC 2015:
Section 1511.3 Roof Replacement shall include the removal
of all existing layers of roof coverings down to the roof deck.
Section 1511.3.1 Roof Recover The installation of a new roof
covering over an existing roof covering shall be permitted
where any of the following conditions occur:
Where the new roof covering is installed in accordance with the
manufacturer’s instructions.
Complete and separate roofing systems, such as standing-seam metal
where the supports transmit the lads directly to structural elements.
Metal panels concrete tile over wood shakes
Application of a new coating over sprayed-in-place foam.
15-KRecover Caveats
IBC 2015 Section 1511.3.1.1
A roof recover shall not be permitted where any of the following occur:
1. Where the existing roof or roof covering is water soaked or
deteriorated to the point that the existing roof is not adequate as a
base for additional roofing.
2. Where the existing roof covering is slate, clay cement or asbestos
tile.
3. Where the existing roof has two or more applications of any type of
roof covering.
16-KExisting Buildings
Project Gross Square
Type? Footage?
Reroof >25,000
Structural
Other
Capacity
Building
Check
Type?
Results? Major
Structural
Upgrade Not
Low-RiseExisting Buildings –
Additional Considerations
No exemptions for:
HVAC interference/relocation
Balconies/decks on the roof
Shading
Slope (even steep slope roofs)
Commonly exempt building types
(religious institutions, non-profits,
schools, government buildings, historic
buildings, etc.)
Gross square footage may be
difficult to determine
18-KAnother Choice:
In lieu of installing a Green Roof you can buy your
way out by calculating the area that would be
required and then paying $25/ square foot instead
of doing the green roof (referred to as “cash-in-
lieu”)
Note that full variances (not exemptions or partial
variances) are subject to cash-in-lieu
19-KMYTH: Green Roofs are
Always 4x More Expensive
Green roofs do cost more than conventional
roofing initially, but exact figures are project-
specific
Initial studies suggest that the cost impact will be
higher on a per-square-foot basis to retail facilities than
other building uses/types
20-KExample 1
• Gross Square Footage: 100,000
• Roof Square footage: 100,000
• Required Square Footage: 40,000 (40% of available roof area)
• Minimum green roof square footage: 12,000 (30% of required area)
Green Roof
(12,000 SF Min.)
Green Roof OR
Solar
(28,000 SF Min.)
21-KExample 2
• Gross Square Footage: 150,000 (3 floors, 50,000 SF each)
• Roof Square footage: 50,000
• Required Square Footage: 25,000 (50% of avail. roof area)
• Minimum green roof square footage: 7,500 (30% of required area)
Green Roof
(7,500 SF Min.)
Green Roof OR
Solar
(17,500 SF Min.)
22-KExample 3
• Gross Square Footage: 100,000
• Roof Square footage: 100,000
• 50,000 SF of solar already installed – available roof area: 50,000 SF
• Required Square Footage: 20,000 (40% of available roof area)
• Minimum green roof square footage: 6,000 (30% of required area)
Green Roof
(6,000 SF
Min.)
Green Roof
OR Solar
(14,000 SF
Min.)
23-KExample 4
• Gross Square Footage: 100,000
• Roof Square Footage: 100,000
• Required Square Footage: 40,000
• Minimum green roof square footage: 12,000
• 6:12 roof Pitch, ridge East-West
• Ordinance requires 30% minimum green roof, but not possible due to pitch
• Available solar area exceeds required area – cash-in-lieu required: ???
6:12
Solar Available 6:12
(50,000 SF) N
24-KExample 5
• Gross Square Footage: 100,000
• Roof Square Footage: 100,000
• Required Square Footage: 40,000
• Minimum green roof square footage: 12,000
• 6:12 roof Pitch, ridge North-South
• Green roof not possible due to pitch
• Solar difficult (no southern exposure) – cash-in-lieu required: $1,000,000
6:12
Variance
(40,000 SF)
6:12
N
25-KGREEN ROOF &
SOLAR BASICS
26-DWhat is a Green Roof?
A surface over occupied space which is waterproofed,
then covered with growing media and plants
27-DTypes of Green Roofs
Extensive Green Roof Intensive Green Roof
• Typically planted with sedums • Large plant diversity
(low-growing, drought resistant
plants) • Can be made accessible
• Drought tolerant • Deeper growing media = heavier
• Minimal growing media = lighter • More maintenance
• Less maintenance
28-DLow Slope Roof Membranes
*some *ballasted only
Built-up Roof (BUR) Modified Bitumen EPDM
Legend:
OK in green roof
Caution using in a
green roof, see note
PVC/KEE TPO
Cool roof
Note: Some membranes will work in a green roof with proper design
and/or back-up systems, but will not typically work well if installed in a
manner similar to how they are installed in roofing. 29-DWaterproofing Membranes
Rubberized Asphalt (Hot or “Peel-and-Stick” Crystalline (vertical)
Cold-Applied)
Legend:
OK in green roof
Caution (see prev. slide)
Never use in green roof
Cold Fluid Applied (Epoxy, Bentonite (Vertical)
PMMA, Polyurea, etc.) 30-DGrowth Media
Growth media (not “dirt” or “soil”)
is an engineered material which is
lightweight, specifically intended for use
on roofs. Growth media consists of:
• Lightweight Aggregate (perlite, peat, bark, crushed brick…)
• Sand
• Organics (humus, compost, clean top soil)
• Inorganic (crushed clay, silt, pumice)
Weight is an important consideration for green roofs;
• Growth media weighs 30-75 pcf dry/unsaturated (60-120 pcf
saturated). 4-inch saturated extensive growth media can weigh
10 to 40 psf
• As opposed to 75-100 pcf dry (100 to 125 psf saturated) for typical
dirt/soil.
31-DVegetation
selection critical for aesthetics (plant color, height, etc.)
Sedums
32-DSite-Planted Systems
Extensive site planting:
Hydroseeding
Plugs
Intensive site planting:
Some grasses/ground cover plants
included in intensive roofs can be
site-planted with hydroseeding or
plugs
Larger plants (bushes, trees, etc.)
typically transplanted as semi-mature
plants
33-DPre-Planted Systems
Trays (extensive and some
intensive)
vegetation
growth media
separation fabric
drainage plate
protection mat.
Mats (extensive only)
multilayer system with:
vegetation
biodegradable felt growth mat
34-DIrrigation
Must be site-specific for the
layout/types of plants
Drip irrigation and soaker
hoses are common for all
types of green roof
applications
Sprinklers / Sprays can be
challenging on roofs due to
higher wind, but are often
used
35-DSolar Basics
Integration of solar cells that produce energy
Membrane selection important for solar performance
Solar loses efficiency at higher temperatures
The temperature ~1.5 ft above a white roof is usually warmer than
~1.5 ft above a black roof
36-DTypes of Solar
Commonly used in low slope roof applications
Photovoltaic (PV) Solar
Panels
Traditional monocrystalline or
polysilicon silicon panels.
Higher output, higher cost.
Thin Film Solar Cells
(Surface-applied PV films)
photovoltaic material (amorphous
silicon) deposited onto the substrate.
Lower output, lower cost.
37-DWind Loads on Solar
Flat panels subject to suction/uplift only (similar to
roofing)
Angled/elevated panels subject to suction/uplift
and pushing pressure simultaneously
Total load typically 1.5-2x higher than suction/uplift alone
Standards
ANSI FM 4476 - Flexible
Photovoltaic Modules
ANSI FM 4478 - Rigid
Photovoltaic Modules
38-DAnchoring Solar Panels
Must resist loads imposed by
wind, as well as gravity/snow
loads
Two methods:
1. Fasten/anchor to structure
Creates penetrations in the
roofing
Harder to disturb from snow, work
on the roof, etc.
2. Ballasted frame
No penetrations
Roof structure may not support
weight required to resist required
uplift/suction loads
39-DSolar Systems – On-Grid
Allows excess power to be sold back to the electrical grid
Requires an inverter to convert DC power from the
panels to AC power for the grid
40-DSolar Systems – Off-Grid
Excess power generated cannot be sold to the electrical
grid
Usually residential systems
41-DPERMITTING
REQUIREMENTS
42-KGreen Roof Declaration
Form (GRDF)
Submittals required to attach to a non-exempt form
include:
All architectural, structural, and MEP drawings pertinent to the
roof (or systems serving the roof)
Drawings and details for a solar system
Landscape/irrigation plans for green roof
Wind uplift letter (signed and sealed by a PE)
Green roof establishment and maintenance plan
Variance request for water collection requirements for any
projects incorporating solar
43-KGreen Roof Declaration Form
(GRDF)
44-K45-K
46-K
47-K
48-K
49-K
50-K
51-K
52-K
Structural Exemption
Use the exemption on the first page
Attach to GRDF signed and sealed letter from a PE which
includes:
Available roof area
Type of existing system
Percent coverage required based on gross area
Load capacity of the existing structure
Load and characteristics of the green roof needed
Narrative describing the required structural alteration
Percentage of the roof which can support a green roof without major structural alteration
Size of proposed green roof and PV (if any)
53-KDESIGN & INSTALLATION
REQUIREMENTS
54-KGreen Roof Construction
Standard (GRCS)
Set of requirements established by the
initiative (Section 10-303, Subsection B)
which must be met for the design and
construction of a green roof
55-KGRCS Requirements 1. Green Roof Assembly 2. Gravity Loads 3. Slope Stability 4. Parapet height and/or overflow scupper locations 5. Wind Uplift 6. Fire safety 7. Occupancy and Safety 8. Waterproofing 9. Drainage 10.Water retention 11.Vegetation Performance 12.Irrigation 13.Maintenance Plan 56-K
1. Green Roof Assembly
57-K2. Gravity Loads
(a) ASTM E2397.05 Standard Practice for Determination of
Dead loads and Live Loads Associated with Green Roof Systems
(b) The Density of the growth media shall be determined:
• ASTM E2339.05 Standard Test Method for Maximum Media Density
for Dead Load Analysis of Green Roof Systems or alternatively
• The designer may use an un-factor, saturated density of the growing
media of 125 pcf
(c) The applicant shall include design loads definition as part of
the “Green Roof Declaration” form which shall be required as
part of the application for building permit
58-DWeight for 4-inches
Taken from Green Roof Solutions web site:
Saturated weight of 45 psf for 4” of media depth
The initiative has the media density as 125 pcf or
41.7 psf.
59-DWeight of media and snow
Denver snow load= 35 psf ground snow load or
24.5 psf roof snow load.
24.5 + 41.7 = 66.2 psf
Just for the weight of the green roof and snow
load.
60-DOther Direct Roof Loads:
Weight of roofing
Weight of drain mat
Weight of protection boards
Weight of R-30 insulation
Weight of roof deck
Weight of any boxes around growing beds
61-DWeight Concerns:
Older buildings in Denver commonly never saw a full
code snow load due to low levels of insulation. The
snow melted.
The new Energy Code increased the R-value to R-30.
The snow builds up deeper and may get to a full code
snow load.
Basically every reroof in Denver will require an
engineering sign off on weight.
62-D3. Slope Stability*
All roofs with slopes in excess of 10° (17%) [2:12] that support
green roof assemblies shall incorporate anti-shear measures.
NOTE: The City of Denver has (verbally) interpreted this and does not require
green roofs on slopes greater than 2:12
* Yes, this applies to sloped roof that are more than 50-ft high for residential
buildings and on any non-residential sloped roof in the City of Denver.
63-D4. Parapet Wall Height and/or
overflow scupper locations
(a) Parapets and Scuppers shall be specified in the design, as
required, to limit retained rain water loads to within structural
limits in the event of obstructed internal drains.
(b) Analysis shall be done join conformance with DBC
64-DOverflow Scuppers
(c) The reference point for overflow scuppers height must be
early indicated to avoid the possibility of confusing the
overflow scupper height as being measured above the
finished green surface or other layer above the
waterproofing resulting in higher water load than accounted
for by the design as indicated in the sketch below.
65-D5. Wind Uplift
The applicant shall provide a report, stamped by an
engineer, [emphasis added] providing wind uplift
pressures being designed for (including a description of
how the pressures were determined), and describing how
the design addresses these pressures.
66-KWind Uplift – Industry Tools
ANSI/SPRI RP-14 is a potential tool for designers,
particularly in early stages of green roof design
Provides tables based on allowable wind speed (not
ultimate), building height, exposure category, and
parapet height that direct designers to an acceptable
“system” (Systems 1 through 3)
Provides minimum weight/descriptions of the ballast
which must be provided for a given system
67-KWind Uplift – RP-14 Example
70 ft high, allowable wind speed of 90 MPH,
Exposure C, 10-inch parapet Requires System 2
68-KWind Uplift – RP-14 Example
69-KWind Uplift - Considerations
FM does not insure in Wind Zones over 100 mph
Denver is over 100 mph everywhere
The industry standard method for pressure
determination is ASCE7-10.
It does not address wind erosion of soils.
No longer permissible to use industry standard wind
uplift designs (such as FM Global fastening patterns)
under a green roof without an engineer’s sign-off
70-K6. Fire Safety
Where roof penetrations, intersecting walls, parapets,
upturns, or mechanical equipment are clad with
combustible materials the design shall include a vegetation-
free zone abutting such features and the vegetation-free
border shall be equal to the vegetation height at maturity
but in no case less than 1.5 ft.
71-DFire Safety – Industry Tools
ANSI/SPRI VF-1
Requires green roofs on slopes over 2:12 to be designed
Requires a minimum 3-foot wide perimeter non-vegetated
zone (as compared to the initiative’s 1.5-foot requirement…)
Provides recommendations for firebreaks, area dividers, etc.
Commentary indicates that roofs which meet certain criteria
can be considered “hard roofs”, which are equivalent to a
Class A fire rating. Requirements include maintenance of the
plants, substrate thickness and content, and use of irrigation
72-DFire Safety - Considerations
Depending on
plant material, dry
sprinkler systems
may be required.
Dead plants are
brush fires waiting
to happen
73-D7. Occupancy and Safety
The applicant shall state, in a green roof declaration form
and the green roof application, the use of the roof and
whether or not it will be accessible to the public.
74-D8. Waterproofing
75-K9. Drainage
Dead-level flat membranes are not permitted under
green roofs for this initiative
76-K10. Water retention
77-K11. Vegetative Performance
In order to support plant survivability :
(a) When structurally possible, the growing media shall be a
minimum of 4 inches; or
(b) The applicant shall provide a report confirming that the
engineered system as designed provides plant survivability
comparable to that of an un-irrigated system with growing
media at minimum 4 inches.
78-K12. Plant Selection
* Cited definition for “noxious weeds” includes invasive species
** Yes, “Urban Agriculture” means growing food
79-D13. Irrigation
Adequate measures shall be provided to permit irrigation
necessary to initiate and sustain the vegetation during the
service life of the green roof.
80-D14. Maintenance Plan (a) The applicant shall develop a maintenance plan for the green roof as per which shall define programs of routine maintenance and inspection to ensure the green roof components perform their required functions for the duration of their design lives. (b) The maintenance plan shall address the requirement of the specified growth media and vegetation for vegetation survival. (c) the maintenance plan shall address re-planting, in the event replanting should become necessary. (d) The maintenance plan shall be submitted with the application for a permit for a green roof. NOTE: Regular maintenance requires access. 81-D
Maintenance
All green roofs
Removal of deadfall, dead plants, raking, etc.
Replanting failing areas/plants
Fertilizing
Irrigating
Cleaning drains/scuppers
Extensive and grasses/ground cover on
intensive:
Trimming
Larger plants on intensive:
Pruning
82-DOwner Buy-in
The maintenance plan is the responsibility of the
owner.
Our advice is have the owner sign off that the
maintenance plan will be followed and the contractor
and the specifier are not responsible the day after the
roof is accepted as being complete.
83-KMYTH: Roofers will have to
hire Landscapers
Roofers can install their own green roofing and/or
irrigation, with the proper licensing
84-KContractor Licensing
City of Denver has implemented a new contractor’s
license for Green Roofing and Irrigation
The green roof license can be obtained by any roofer with 2
years’ experience in the green roofing field (must be green
roofing, landscaping alone is not sufficient)
The irrigation license can be obtained by any contractor with 2
years’ experience in the trade
85-KNEXT STEPS
WHAT HAPPENS NEXT WITH DENVER’S
GREEN ROOF INITIATIVE?
86-DTask Force vs. Advisory Council
Initiative City of
Denver
Green Roofing
All Other
Construction
Provisions
Standard Created Green Roof
Review Task Force
GRRTF providing
TAC will recommendations
(GRRTF), has been
maintain GRCS on all other meeting since
provisions
February, Last 2
meetings in May
Included requirement to
create Technical Advisory
Council (TAC), member
selection still pending
87-DTask Force Progress
Proposed major amendment to the initiative which would
introduce a system to qualify as a “green roof,” even if no
actual plants are installed
Proposed system would be similar to LEED, and would
include points in 4 categories:
1. Urban Heat Island - cool roofs (Energy Star rated)
2. Green Experience - vegetation (3% of required area)
3. Water & Storm Water Management
4. Climate - Greenhouse Gas Emission Reductions
(using calculator based on building size, energy star rating…)
Currently multiple ways to achieve required score in the 4
categories. Equivalent to environmental benefit of Green Roof
Initiative while meeting C&C Denver environmental goals.
88-DTask Force Progress (Cont.)
Task Force recommendations to be reviewed by
“Green Roof Advisors” industry professionals
gathered by the City and County of Denver to
provide advice and inform
Final recommendations submitted to Denver City
Council for review and possible adoption.
Two city council members currently on the Green Roof
Task Force
89-DCity Council
July 1, 2018 is the first time the initiative can be
amended, modified, or repealed
All changes to the initiative (including repealing it) would
require a super majority vote of City Council
90-DMYTH: Repeal is Coming
City Council has publicly stated that they feel it is
imperative to honor the voter’s intent by keeping
the initiative
91-DMYTH: The Initial
Amendment will Solve it all
Chances are we’ll need to live with a Green Roof or
Environmental Initiative and continue to provide input to
our lawmakers
Potential issues which will remain:
Extreme weather will continue to adversely affect roofing
performance
White roofs (being considered as an alternate compliance method)
encourage condensation when not properly designed
Urban Heat Island has a high contribution from roads and parking
lots
May still need an “approved systems” library (similar to RoofNav)
92-DPROJECT PROCESS
CONSIDERATIONS IN THE DESIGN AND
BUILDING OF GREEN ROOFS
93-KDesigner Involvement Services required from Designers: Structural assessment of existing buildings – must be signed and sealed by engineer Wind load calculations/letter – must be signed and sealed by engineer Testing of waterproofing prior to green material installation – Test letter must be signed by engineer/architect Specifics for growing media depth, water retention, drainage, positive slope to drain, non-vegetated zones, etc. Contact a qualified designer to assist with requirements if needed 94-K
Develop Partnerships
Roofing contractors with landscapers and irrigation
companies
Owners with landscape/irrigation maintenance
companies
95-KCity of Denver Forms
Apply for proper contractor’s licensing
Fill out GRDF for all new building or reroofing
permits
96-KAvailable Standards
ANSI/SPRI RF-14
Wind
ANSI/SPRI VF-1
Structural Design, Waterproofing, Slope, Firebreaks, Area Divider, Border Zone,
Maintenance
ASTM E2400 / E2400M
Selection, Installation, and Maintenance of Plants for Green Roof Systems
FM Global Technical Advisory Bulletin 1-35
LEED (Leadership in Energy and Environmental Design)
NRCA (National Roofing Contractors Association)
USGBC (United States Green Building Council)
97-DQUESTIONS?
• City of Denver GRI Website
https://www.denvergov.org/content/denvergov/en/d
enver-development-services/commercial-
projects/green-roof-initiative.html
• Copy of Presentation
http://coloradoroofing.org/member/education/
PRESENTED BY:
Kade Gromowski, P.E., RRC, RWC - Pie Consulting & Engineering (www.pieglobal.com)
Rich Boon, P.E. – Construction Support Services
Dan Cupit, RC, BSCE – Professional Inspection Services (www.pcsden.com)
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