1. Green Roof Study
To conclude our presentation today, please allow me to summarize the results of a two-year study on an ICF/Green Roof structure.
In partnership with Canada Mortgage and Housing, our company participated in a study to determine the contribution of green roofs to the performance of buildings. Our Roof Evaluation Module at British Columbia Institute of Technology, Centre for Architectural Ecology, was the first concrete structure ever the subject of this kind of study.
Here is how it all went: 1

2. A “Pan Form” for T-Beam Slab Construction
How Does it Work?
A “Pan Form” for T-Beam Slab Construction
These ICF forming products are what is called a “pan-form” for concrete.
The forms are placed into position with reinforcing bar set into place according to the structural design. Concrete is then poured across the forms to a level that meets the design specifications, leaving a T-beam shape in the concrete.
T-beam construction is well-known technology, and supports some of our largest and most durable structures, like bridges and parking garages.
The ICF floor & roof forms yield a smaller version of that same technology.
Lets learn a bit about how a T-beam functions.

3. Achieves Design Objectives
Safely carries expected loads
Maintains building shape and structural integrity
40% lower mass reduces accelerated loads
Long span capacity
© 2013 Quad-Lock Building Systems, Ltd
Taking away the insulation, this image shows the concrete structure that is created by the ICF system.
Significant savings are seen in both concrete and reinforcing steel, as compared to a full concrete “two-way” slab design. 3

4. Compare Concrete Slab vs. ICF T-Beam
25'-0" Single Span: 8" Concrete 50 psf LL
Concrete needed
37 cu.yd
Top Reinforcement
O.C. E/W
1872 LB
Bottom Reinforcement
O.C. E/W
4209 LB
6081LB
150,000 lbs
75,610 lbs
25'-0" Single Span: 11" QD + 2.5" 50 psf LL
Concrete needed
18.4 cu.yd
Top Reinforcement
6x6 WWM
288 LB
Bottom Reinforcement
24" O.C.
2883 LB
Quad-Deck Z-Strips
12" O.C.
900 LB
4071 LB
Lets compare the material consumption on a conventional two-way suspended slab versus a one-way T-beam design.
First we compare the concrete consumption, then we look at the steel reinforcing.
Both structures clear span 25 feet, and cover about a 1500 sq. ft. area, and have a live load of 50 lbs psf.
The two-way slab requires 37 cu. Yds. Of concrete, and consumes nearly 6100 lbs. of reinforcing steel.
The T-Beam structure requires 21 cu. Yds of concrete, and just over 4000 lbs of steel. That is a 43% reduction in concrete, and in weight of the structure.
The steel consumption is reduced by 33% in this example, all components considered. 4

5. Check it out at www.greenroof.bcit.ca
Quad-Lock Green Roof
British Columbia Institute of Technology
Centre for Architectural Ecology
I would like to invite all of you to visit our green roof research partnership at British Columbia Institute of Technology’s Center for Architectural Ecology
This is a picture of our “Roof Evaluation Module” which features ICF walls and roof structure, with a 4” planting layer on top.
The REM is monitored both for temperature and rainwater run-off, and compared with conventionally constructed specimens. This will help to document the energy savings of a green roof, the reduction in heat-island effect and the mitigation of rainwater runoff, all of which are very desirable sustainable features.
Visit the center’s site at:
Roof Evaluation Module
Check it out at 5

6. Roof Evaluation Module
On the left is our Roof Evaluation Module, immediately adjacent to the research facility (at right), which was built using conventional wood-framed construction, common to BC and most of N. America.
The roof of the research centre was divided into three sections. The middle section was designated the “control roof” and was sealed with a conventional built-up roofing system, which was fairly light in colour. The two adjacent sections were designated green roof plots, and planted with 3 inches and 6 inches of growing medium, respectively.
All sections received instrumentation at every layer of the structure to monitor heat flux and storage over a complete seasonal cycle, as well as the amount of storm water runoff versus total rainfall. 6

7. R-10 Insulated Slab
First, an insulated slab was poured to support the REM. 7

8. ICF Walls & Roof (Both R22)
Then, an ICF structure, walls and roof, was constructed to support the green roof layer. Both walls and roof were of R-22 ICF construction. 8

9. Plantings
As you saw in the last frame, a planted layer was added, utilizing pre-planted trays that were brought to the site from a local nursery. The plant mixture was mostly sedums, but as you will see, other species did eventually get established. 9

10. Heat Flux Monitors
During the planting process, electronic heat-flux monitors were placed in both the planted layer and the structure, so a complete heat-flux profile could be developed. This was the same equipment placed in the control structure next door. 10

11. Storm Water Collection
The roof structure was built with a 2% slope, so rainwater not utilized by the planted layer could be collected and measured throughout heavy rainfall events.
The lower right of the photo shows a perforated aluminum boundry, which allowed excess water to fall into a gutter system at the extreme right.
This was carried into the structure, where a collection device was measured electronically. This was compared to the total rainfall hitting the structure, which was calculated using rain-gauges immediately adjacent to the structure. 11

12. The Results: Storm Water Retention Green Roof Layerby
Green Roof Layer
45 % better retention
94 % better retention
69 % better retention
Wet Season
Dry Season
Annual Average
OK, so what were the results?
First, lets look at the amount of storm water retention exhibeted by our green roof versus a conventional roof. Now Vancouver is a rather wet climate, which means that the results will differ in drier climates.
During our wet, winter season, the green roof retained 45% more water than the conventional roof. In our dry season, the green roof retained 94% more water, which means that almost NO water was available to potentially be processed in a municipal drainage system. Even during Vancouver’s wet season, almost half of the water was retained.
Over the full year cycle, the green roof retained an average of 69% more water than it’s conventional counterpart next door.
Bottom line, this means that
1)our green roof structure offered 69% less impact on a municipal water collection system
The flow of that water was delayed into “off-peak” hours, reducing the potential for the municipal system to be pushed over capacity
And in many cases, lower impact fees may be charged at the time of permitting, if such reduction can be demonstrated.
69% Less impact on municipal water collection systems
Flow delayed to “off-peak” times
Lower impact fees charged at permitting 12

13. Reduction In Heat Flow Through Roof Structure
The Results:
Reduction In Heat Flow Through Roof Structure
Heat Loss
Heat leaving the building
Heat Gain
Heat entering the building
50 % (winter)
77 % (summer)
98 % (winter)
100 % (summer)
Now lets compare heat flow through the structures.
The ICF/green roof structure demonstrated a 50% reduction in heat leaving the building during the winter months, and a 77 percent reduction during the summer months. This is of great interest to those in heating climates.
For radiant heat entering the building, almost 100% was prevented over the entire year, compared to a conventional wood structure and roof. Were I living in an area where cooling is the biggest concern, I would certainly be paying attention to this. 13

14. The Results: Reference Roof ICF Green Roof
Here is a bar graph for each structure over the entire year.
Upper left is the conventional build. Lower right is the ICF/green roof REM.
Anything above the line is heat entering the building.
Anything below the line is heat leaving the building.
Note how not only the quantities of heat flow are smaller, but the extremes are less pronounced. This means a much more efficient thermal enclosure which yields a more constant and comfortable inside the building.
ICF
Green Roof 14

15. The Results: 24 Hr Heat Flux July 26, 2009 Reference Roof ICF
The “stopping power” of the ICF/green roof structure is easily seen on one of the hotter days in July of 2009.
Again, anything above the line is heat entering the building, and below the line is heat leaving the building.
The upper left is the conventional structure. The lower right is the ICF REM. Look at the amazing consistency in the REM.
ICF
Green Roof 15

16. Integrated ICF Building Shell
This is our vision of the building shell of the future:
This detail shows a green roof supported by an ICF T-beam floor, monolithically joined to an ICF wall. 16