Why RhinoBond is becoming the preferred method of commercial roofing attachment.
"RhinoBond" – If you are in roofing you have most likely heard of this system or a similar “induction welding” roofing system. What is it and why is it gaining so much traction? Fewer screws, less membrane and, bad for Vulcan Heat, fewer seams to welded. Let’s break down this system to better understand why it is better and why it is becoming so popular.
Traditionally there are two types attachment methods for single ply membrane; mechanically attached & fully adhered.
Fully adhered roofs require an expensive machine to dispense industrial glue onto the roof. Most of the time this glue is installed in a ribbon pattern by first gluing the insulation, then the membrane. While the glue holds onto the fleece back membrane extremely well, the ribbon pattern can be seen from the top of the membrane. This can affect the drainage of the roof leaving areas of ponding water and a not so aesthetically pleasing appearance on the roof.
Fully Adhered Roofs –
200 Square job comparison:
200’ x 100’
Most adhesive sets with a machine yield 20 squares per set at 12” on center bead pattern.
2” Insulation installed with glue over lightweight concrete: 10 sets to cover 200 squares.
Single ply membrane installed with glue over insulation: 10 sets to cover 200 squares.
Total for glue: 20 Sets
*Cost for glue machine: $7,000 plus maintenance
Pros:
All membrane is firmly secured down.
Seams 3” overlap for head welding.
Cons:
Expensive machine to install glue.
Temperamental glue to put in expensive machine.
Mechanically Attached Roofs are strait forward. You put a row of screws into the seams of the membrane. Sounds easy right? It is!
If your job was the same as the scenario above, 200’ x 100’, you would follow the steps below to install the roof:
Lay insulation.
Install insulation with insulation screw and insulation plate.
Roll out 5’ membrane roll for picture framing around permieter.
*Mechanically attaching does require picture framing - See picture under "Half Sheets".
Use seam fastener and seam plate to install membrane.
Continue across roof with 10’ rolls until you reach the other side and then finish with a 5” roll.
Mechanically attaching requires:
2 different plates
2 different screws
2 different size membrane rolls
200 Square job cost comparison:
200' x 100'
2” insulation installed with 6 plates & 6 screws per boards: 3,100 each: 6,200 plates & screws.
Single ply membrane attached with seam plates and seam fasteners into steel every 6”: 2,400 each: 4,800 plates and screws
Total Plates and screws: 11,000
5” Rolls for picture framing: 6 rolls at 3,000 SQ FT
10” rolls for field – 19 rolls at 19,000 SQ FT
Pros:
Easy to install.
Most common single ply attachment method.
Cons:
Multiple items to estimate.
Can be noisy on top floors in high wind due to membrane flutter.
Now that we understand both fully adhered roofs and mechanically attached roofs, we can better understand RhinoBond which is a Hybrid of both systems.
RhinoBond uses a technology that allows the plate to be welded to the membrane from underneath the membrane without apply any direct heat.
The RhinoBond system combines the advantages of both the fully adhered and the mechanically system. It eliminates the seam plates and seam screws, it eliminates half sheets and allows you to use a 3” overlap vs. a traditional 6” mechanically attached overlap. Here’s how.
Using the same 200’ x 100’ example roof as before, you begin by laying out your insulation. The insulation is attached with a RhinoBond plate and what used to be a seam fastener.
These are laid out in a grid pattern so they are easily found later on once the membrane covers the plates.
Once the insulation has been installed, a full 10’ wide membrane is rolled out and heat welded to the next 10’ wide roll.
Once you have all of your insulation installed and your rolls heat welded across the roof, you can then begin attaching the membrane with OMG’s RhinoBond machine, or a similar induction welding tool.
Welding a Rhinobond plate takes about 6 seconds per weld. The welding is followed by placing a heat sink magnet on top of the hot plate to ensure that the membrane bonds to the plate as it cools.
RhinoBond attachment requires:
1 plate
1 screw
1 size membrane roll
200 Square job cost comparison:
200' x 100'
2” insulation installed with RhinoBond plates and screws: 4,000 each:
8,000 plates & screws
Single ply membrane attached with RhinoBond induction welding.
10” rolls for field – 21 rolls at 20,500 SQ FT
Pros:
One screw, one plate, one roll
Easier to estimate
Cons:
Tedious plate installation
Cost of RhinoBond machine - $7,000 one time investment
Now that we understand all three systems, lets look at the huge advantages that RhinoBond offers:
No Point Loading / Displaced Uplift Values
- When a mechanically attached roof is installed, a row of fasteners in installed into the seams every 6”. This row and the row on the other side of the 10’ sheet is all the hold down the membrane. This causes two problems: point loading of the deck and potential flutter of unattached membrane. Point loading in one area can cause deflection in the deck in high wind areas.
This photo shows the extreme effect of the uplift values. On the left, is a mechanically attached roof with the roof only being held down at the seams.
On the right you can see how RhinoBond performs with dispersed uplift values working to achiever great uplift across a wider area.
Extreme cases of this have shown roofs that were mechanically attached still assembled, but detached from the structural purlins.
No Penetrations
- A big selling point of the RhinoBond system to the building owner is the ability to install an entire roof without putting a single fastener though their brand new membrane. When competing with other cost effective mechanically attached systems, this is a big selling point if the previous owner had problems with leaks from holes or poorly welded seams.
Mechanically attached roof install shown below:
No Half Sheets
- RhinoBond allows for you to install a “mechanically” attached roof with the benefits of fully adhered. This removes the need for gathering costs for half sheets, moving more rolls around on the roof, and ultimately welding less seams.
Faster Dry In
- With the ability to install insulation, loose lay membrane and heat weld the seams, you have the ability to get dried in faster. From recent market studies, a lot of roofing contractors using RhinoBond are able to install up to 100 squares of installation, lay out ten rolls of membrane, heat weld the seams and make the roof watertight.
Additionally, by using this method you can form two crews: an install crew & a RhinoBond crew. One crew will come in to install the the insulation and heat weld the seams. The second crew will come in to weld the RhinoBond plates, finish the detail work and complete the job. This allows both crews to work in sync and maximize productivity.
Typically 40% Fewer Screws
- If you are still not sold, consider this factor. When comparing mechanically attached systems to RhinoBond, RhinoBond typically uses 40% less fasteners. This means that 40% less holes will be in your metal deck making it less like Swiss cheese. If you were to take the 200 square job comparisons, you are looking at some similar number below:
Mechanically attached total screws and plates:
11,100
RhinoBond total screws and plates:
8,000
Mechanically attached total membrane:
21,000 SQ FT
RhinoBond total membrane:
20,500 SQ FT
Mechanically attached seams:
2,500 Ft
RhinoBond seams:
2,000 Ft
When comparing these numbers, ask your self one thing: How long does it take you to install 3,000 less fasteners and weld 500 feet less seams.
OMG Roofing Products has a tool online to compare numbers between these systems. This tool can be found online at
https://www.omgroofing.com/rhinobond-calculator.html
The advantages of RhinoBond being a better roof paired with the labor savings at install shows that RhinoBond is the future of roofing.
Vulcan Heat has a commitment to the roofing industry as well as the roofing contractor to provide value. While this article shows that fewer seams are being welded with Vulcan Hot Air Products, we want you to be informed of the most up to date roofing information.
We hope this article has been helpful and informative. Message us for any questions you may have and good luck welding!
-Vulcan Heat Staff
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