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Frequently Asked Questions

We have listed here all the questions we are most frequently asked about the Tensio system.

Why buy a Tensio system for snow on your roof?

Will the acquisition of a Tensio system please my building insurers?

Absolutely! In fact, some world-renowned insurers consider Tensio to be the optimum snow monitoring method for buildings, since it's the only one that monitors the behavior of building structures in real time.

Your insurer should be delighted to learn that you're providing sound preventive maintenance for your buildings with a proven, reliable solution like Tensio. 

Eventually, you may even have to take a less conservative approach to snow removal, since you'll be able to prove to your insurer that you're not jeopardizing the integrity of your building(s). 

I've never needed to clear snow before, why should I install a Tensio system?

Unfortunately, without a Tensio system or regularly calling in engineers for weighing service, it's impossible to know whether you've ever needed to clear snow, or whether you will need to do so in the future.

Added to this is the fact that no two winters are alike, either in terms of precipitation quantity or duration.  

Moreover, a Tensio system is useful all year round, as it can also help to detect clogged drains and prevent major damage such as water infiltration and worse.
What's more, according to the Computer Research Institute of Montreal, CRIM, the impact of climate change has already begun and will continue to disrupt weather patterns in the future. For example, since 2010, there has been between 14% and 20% more precipitation (in all forms) each year than during the entire 1975-2010 period. 

Warming can also create rain showers in the middle of the winter, adding considerably to the weight of the snow load on a roof.

Why isn't snow height a reliable indicator of whether or not I should clear snow from my building's roof?

The height of the snow will never tell you how much stress the building structure is under. It can therefore be a dangerous indicator to use, as it doesn't prevent the risk of overloads that could lead to catastrophic consequences, such as a forced business interruptions or, worse still, a catastrophic collapse.

Every building has its own capacity limits, and each section of the same building may have a different limit from another, depending on a multitude of factors. The only reliable indicator is one that monitors the behavior of your buildings' structure, in real time, and Tensio is the only preventive maintenance solution on the market that can do this.

Without a Tensio system to monitor, in real time, the structural stress undergone by a building's structure, organizations ideally are forced to send people onto the roof to carry out measurements by hand. Often this means putting employees at risk.
This data should then be compared with to the limits of each roof location, usually by an engineer. Also, this process ideally needs to be repeated every day, depending on weather conditions, which makes this process both energy-intensive and complex.

How does the Tensio snow system work?

What's a Tensio system?

A Tensio system consists of 3 key elements:

1. Engineering calculations to determine the different load capacities your building's roof can support, for each roof location.

2. The installation of intelligent sensors at critical locations within the steel structure of your building's ceiling to measure, in real time, the snow load supported by your roof.

3. A web application in which sensor data is cross-referenced with weather forecasts for the next 7 days (precipitation, temperature and wind). So if a storm 4 days from now is likely to cause a location to exceed its limit, Tensio alerts you in advance.

Find out all the details here:

Can a Tensio system be installed on a residential home?

Unfortunately not. At present, the Tensio solution is only suitable for industrial, commercial and institutional buildings. 

Tensio's intelligent sensors have been designed to measure steel elasticity caused by the weight of the snow load on the ceiling structure of buildings, such as beams or joists. Given that residential properties are normally wooden structures and that moreover the roof beams are generally not easily accessible; the Tensio solution cannot be adapted to the needs of individuals at the present time. 

Does Tensio only work on steel structures?

For the time being, yes. However, our team of R&D engineers is currently working hard to develop a solution that will also meet the needs of wood and concrete buildings. 

We invite you to subscribe to the Tensio newsletter (at the bottom of our website) to keep up to date with the latest news.

Pricing and Return on Investment (ROI)

How much does a Tensio system cost?

The price of a Tensio solution varies from building to building, depending on a multitude of factors. For example:

- Several roofs of different heights (versus one large flat roof)

- Additions from different years

- Presence of equipment on the roof

- Total area to be covered

- Firewalls or very thick walls that don't let the wifi waves through (requiring more than one connecting gateway). 

For more details, see our Pricing section:

How many intelligent sensors do I need for my building?

The number of sensors to be installed depends on a number of factors. If we were to rely solely on best practices, we'd install sensors every 60 feet, but this is often excessive and can potentially significantly reduce the ROI of the project.

Generally, we'll start our analysis by questioning the person in charge of preventive maintenance for the building's roof and inspecting the roof to find out where snow accumulates during the winter.  

We'll then make sure that changes in roof elevation (high and low roofs) are adequately covered by one or more sensors, since these are the areas where snow tends to accumulate most.  

Once we've covered the areas prone to snow accumulation, and heard about your building's experience over past winters, we may recommend a few more sensors to make sure there are no shady areas. Potentially after a snow, we sometimes find, on a high roof, a snow drift that was mistakenly overlooked.

This is often done on a case-by-case basis, but on average between 8 and 12 sensors are installed. Purely as a guide, here are the average number of sensors we install on different roof surfaces:

- 50,000 sq. ft. and under: 6 sensors

- 50,000 to 100,000 sq. ft. : 10 sensors

- 100,000 to 200,000 sq. ft. : 12 sensors

- 500,000 ft2 to 1,000,000 sq. ft. : 14 to 20 sensors 

For more details, see our Pricing section:

What will my ROI be, and can you guarantee that there will be one?

The answer obviously depends on the level of precipitation, wind and temperature in the coming winter, as well as your past snow-clearing habits.  

Over the years, all Tensio customers who used to previously clear their roofs of snow every winter have saved at least one snow removal following the installation of a Tensio system in their building(s).

What we can guarantee, however, is that you'll have reliable, accurate data to enable you to:

1. Clear snow only when it really makes sense to do so, at the right times, AND in the precise areas of your roof that really needs it.

2. Save on the cost of trucking snow away (which often equals half the bill for snow removal) by knowing where snow only needs to be spread on your roof, rather than completely removed and disposed of offsite.

So, even if you need to clear snow next winter, Tensio could save you thousands of dollars, because you'll be able to tell your snow shovellers exactly where to clear, where not to clear, and whether snow from location X on the roof only needs to be spread over location Y, which is less stressed by the snow load.  

With the Tensio system you'll be able to show that you're engaging in optimum preventive maintenance for your buildings' roofs, and that you're helping your organization to avoid harmful consequences such as forced business interruptions or, worse still, a catastrophic collapse.

How long does the warranty last?

We offer a 3-year warranty on our equipment, and take responsibility for our engineering calculations.

What's more, even outside the warranty period, our Customer Service team keeps a close watch on technological developments, enabling us to identify potential problems before you even realize they exist.

System Operation

Are structural drawings needed?

We know that, for various reasons, structural drawings are not always available. Don't worry, though, we don't need them. 

What we do need is : 

- The year the building was constructed, for each section (if the years of construction differ, for example if there were annexes added to the main building after the initial construction of the main building);

- If there have been any neighboring additions built up around the main building since its original construction (e.g. wind-blocking silos built 15 years after the initial construction).

Once the Tensio sensors have been installed, our technicians will carry out structural measurements of the building using our own equipment. These readings, combined with the information mentioned above, will be sufficient for our structural engineers to analyse the engineering calculations specific to your buildings.Then, we will present them to you for validation. 

Who determines the load-bearing capacity of my roof?

Our structural engineers use the data collected by our technician during the structural measurements of your building to ensure that the legal conditions are met for both: the sustainability of your company's operations and the health and safety of your building's employees and users. The results are then communicated to you.

What equipment is required for installation?

To install Tensio sensors, we'll need lifting equipment (which most organizations already have on site), such as a cherry picker, a stepladder or some sort of aerial work platform. 

When you already have the equipment on site, and it's possible for us to use it; this generally generates a reduction in acquisition costs on your side. Otherwise, don't worry, we'll bring the equipment we need. 

The height of the ceiling and the width of the available space will determine the equipment required (a rare example: the roof structure accessible through a suspended ceiling, but 10' above the suspended ceiling).  

When you have the equipment on site, we can use yours and save you money; otherwise, we'll take care of renting what we need.

How many gateways are required?

The sensors send the collected data to a gateway, which in turn communicates it to Tensio's servers for processing and display on your customer portal via the Tensio Web application. Unobstructed, a gateway can reach a sensor at a range of up to 1.5 km; needless to say, in the vast majority of cases, a single gateway is sufficient. 

There are, however, a few exceptions requiring the installation of one or two additional gateway(s) when the configuration of the building means that the signal does not pass through easily.  

Obstacles for signal transmission : 

- Presence of metal wall(s);

- Presence of refrigerated areas (freezer, refrigerator).

If your building has any of these elements, you may need more than one gateway when installing the Tensio system, even if the number of sensors required remains relatively low.  

Since every building is unique, it is by discussing with the organization that Tensio's building engineering experts are able to estimate, using a satellite image of the building's roof, how many sensors and gateway(s) will be required to ensure sound preventive maintenance of the roof.

If any doubts remain following this discussion, one of our experts can travel directly to the building site to validate everything precisely.

How long does it take to install a Tensio system?

Installation takes around 30 to 60 minutes per sensor (in most cases, around 40 minutes per sensor), so one day is often more than enough, and sometimes it takes less time. 

Installation time depends largely on the level of accessibility to the ceiling at the sensor locations. If the ceiling structure is easily accessible, installation takes just a few minutes. 

In the vast majority of cases, the Tensio solution can be installed discreetly, without disrupting your organization's activities.

IT Requirements

The signal transmission is difficult inside my building. Will the sensors work?

Yes, they will work, not a problem. A few alternatives are available if cellular network reception isn't working properly in your building:

1. We can always use your organization's Internet network, if it's accessible and you don't mind.

2. If signal transmission still doesn't work, or the option of using your internal Internet network isn't available, we can simply add additional gateway(s) to ensure optimal signal reception. This step is a little more expensive, however, as it involves more equipment. 

What are the IT requirements for implementing a Tensio system?

None. We use our own network (Bell Mobility) and the data is accessible via our Tensio Web application (no software to install).

In short, no intrusion into your internal computer network or your Internet network!

Discover Our Lastest Resources

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