How to minimise the total cost of evaluating and strengthening existing towers

TowerXchange always enjoys a dialogue with Henrik Kamstrup and his team at Intelli Towers, a unique analysis and design engineering company that focuses on tower values, designs, lifetime and capacity upgrades. Over the years, Henrik has experienced that towerco’s often don’t get a correct impression of their tower assets due to low quality assessments reports and fake pictures.

TowerXchange: What is your experience on various tower assessments in emerging markets?

A site assessment must always be an objective exercise in order to provide the correct judgement of the tower. If a tower-supplier and/or executing subcontractor are hired for the assignment, the focus can be of various characters and not the optimal solution for the towerco since the core expertise for these companies is the onsite build and not the static analyses.

Also it is of importance that the tower assessment is done in a proper way as the consequences can be huge. We have seen examples where pictures are linked to a report about the site, but the pictures are from another site - and pictures are important evidence and part of the basic information for the static analysis. In all cases, it is important that what is measured and pictured on site, is the same information provided in the static analysis. In our system, we have a feature that automatically uploads the pictures taken at the exact location using its coordinates, which is why configuration and safety issues are eliminated.

We have seen several assessment reports looking very nice and using to standard reports and tools, but looking into the content and details it’s worth nothing due to the data input being wrong or tools are not used correctly. But from a layman’s point of view it looks impressive and that is a disaster as the towerco should be able to rely on these assessments and plan their investments accordingly.

TowerXchange: Tell us what is of importance for the towercos, whether they are buying, or just maintaining towers?

It is of high importance that the selected executing parties work in an objective way with one focus only: to verify that the existing tower and foundation has the necessary bearing capacity/strength without any need for reinforcements or tower swaps. Further, it is of high importance to verify the remaining life time of the total structure (including the foundation) and that the tower is ‘safe’. Important structural items to consider when buying:

Is existing documentation available and is it liable?

Does the existing documentation include:

•      Tower geometry

•      Profile and bolt dimensions

•      Steel quality/strength

•      Loading and levelling

•      Production place and date of the tower

•      Date of erection on site

•      Pictures of assembly

•      Pictures of foundation depth and reinforcement before concrete casting

•      Pictures of final foundation before backfill (if used)

•      Geotechnical report

TowerXchange: How can Intelli Towers increase tower capacity without physical and costly strengthening of the towers?

Todays research has changed the safety philosophy so we can reduce the uncertainties around some parameters, whereas “in the old days” we had to be “on the safe side”. Using the latest norms and proven methods of optimised calculated effective wind areas of antennas, cables, MW’s et cetera, and further using the actual wind speed (and not an overall) for the exact physical site location, provides great savings. This is not just a theoretical exercise, as it will mature into significant savings on upgrade by using state of the art design research, norms and experience.

TowerXchange: Give us some examples of where strengthening is most effective?

In the cases where strengthening is necessary, the greatest effect you will receive usually comes from the most simply designed towers, i.e. towers with as few members as possible. Having multi-profile towers, such as transmission-towers with a multiple secondary bracings, means the effect of reinforcement is limited compared to simple V-lattice towers.

TowerXchange: What do you think should be the minimum sample size for a site assessment in a due diligence phase?

In our experience, 10-20% would be sufficient but the final number depends on the total amount of towers with a globally chosen spread across the country or area of the tower placements. It is important to confirm whether there is an overload of the same design of towers within the chosen 10-20% or not. If not, the case probably requires expert support.

TowerXchange: We recently featured an interview in which it was suggested that a number of towers sold in Brazil may not be suitable for upgrade and co-location – what’s your view on that?

We have encountered a very few towers which need to be dismantled and replaced. We’ve designed rectification projects for old corroded towers erected in the 1970’s and 80’s and even then you can often extend both the tower’s lifetime and capacity. So I would be surprised if there were that many towers in Brazil that could not be upgraded for co-location. And as said before: It’s now possible to take advantage of the latest research and usage of the latest norms.

TowerXchange: Finally, please sum up what you think should be the priorities when evaluating a portfolio of telecom towers.

There are several key questions I believe buyers and investors in towers should consider:

1. How trustworthy is the seller’s asset register?

2. Do you have the correct estimated value of the assets and on what basis?

3. Is there sufficient bearing tower and foundation capacity available for the placement of future tenants?

4. Do you need to build clauses into the deal to protect yourself against substantial deviations between what is reported and what is actually on any sites you do not visit during the due diligence process?

5. Do you have to invest substantial capital to strengthen the towers you are considering acquiring?

6. Once you’ve acquired the towers, how can you add more bearing capacity at the lowest possible cost?

7. How can you evaluate and update the existing concrete, non-documented foundations at the lowest possible cost?

8. How do you extend the lifetime of existing structures, for example corroded towers along the coastline?

9. When you participate in a build-to-suit program for the future network expansions, which type of towers and foundations (design, capacity, life time and reusable foundations) do you need to install?

10. Do you know how to purchase and install the markets most competitive towers and foundations?

The most important consideration isn’t the cost of the static analysis, the most important thing is total cost of the project and the time line. If you accept a minor extra spend on static analyses and thereby take advantage of our specialised software and general expert experience, we can help the towerco’s save significantly on:

1. The upgrade costs by reducing the capital deployed per tower e.g. from US$20,000 to US$5,000 or less. As mentioned we have experienced several cases where you can strengthen a tower for free (i.e. the cost of the static analysis and no other cost) by using the latest norms and standards correctly, and by simply taking into account the correct location of the actual tower and the load

2. The built-to-suit cost of towers and foundations

3. Losses in asset value due to limited lifetime of purchased structures