Why Installing Solar Panels on an Asbestos or Cement Roof is a Bad Thing! MyZA

With loadshedding and the high price of electricity driving more and more people to install solar solutions on their roofs we are finding more and more clients wanting to install systems on roofs that are not 100% suited to such installations.

Straton Solar note three main ‘roof’ reasons for refusing to do solar installations:

Slate roofs with steep pitch
Roof trusses secured with nails and not nail plates
Asbestos and Cement Sheet Roofs

1. Slate Roofs:

These present special challenges as most have a very steep pitch and the likeliehood of making mistakes when securing panels are high and expensive.

2. Roof Trusses:

Many older homes trusses are secured to each other using nails and NOT nail plates. Nail plates offer a secondary form of support that ensure that the roof trusses do not move under high winds – any form of movement on the roof will eventually work the rails loose that solar panels are secure to and result in another very expensive mistake.

3. Asbestos:

We are all aware of the dangers of working with asbestos and still come across clients who are willing to take the risk. What they are not aware of is that the South African Department of Employment and Labour issued an instruction on 9 November 2022 stating; “Departmental Inspectors have been instructed to not allow asbestos work that entails the instillation of any panels or sheets onto existing asbestos roofs.”

In the notice the Department says:

This correspondence aims to clarify any confusion and non-standardization around the installation of solar panels or “over-roofing” sheets onto existing asbestos roof sheets.

The Department of Employment and Labour (hereafter the Department) is aware of some building owners and clients who wants to install solar panels or “over-roofing” sheets on existing asbestos roof sheets, as type 2 asbestos work.

The Asbestos Abatement Regulations aims to eliminate the risk to health of asbestos in place. To this end, certain activities performed on asbestos in place are prohibited or restricted. Through the requirements of an asbestos management plan, all employers must make provision for a final phase out date as per regulation 6 (2) (c). In addition, certain activities are prohibited in regulation 14.

The drilling into asbestos cement roof sheets at any speed may release fibres and will be increasing the surface area of the asbestos material causing asbestos dust. Replacing screws or even using existing screw-holes will cause risk of abasing the asbestos roof sheets and release fibres during the process of installation and afterwards. Although processes could well be controlled during installation, after installation the client’s employees are still left with the asbestos material in place, but now with a greater surface area for asbestos fibre release, possible damage to the sheets that was worked on, and a greater possibility for abrasion of the asbestos materials due to the slightest movement. The asbestos roof sheets will be left in place on the building and eventual abatement of the asbestos will be VERY unlikely. This is against the intention of the Asbestos Abatement Regulations 2020.

Furthermore, with solar panels or “over-roofing” sheets installed over asbestos roof sheets, inspection of the condition and maintenance will be physically restricted, if not totally prevented.

Approved Inspection Authorities are requested to communicate this to potential clients as well as Registered Asbestos Contractors (RACs).

If the HEALTH reason does not scare you then maybe the FINANCIAL reason will; “The life of a solar panel is minimum 25 years so ideally the roof on which it is going to be installed should also last for at least 25 years. But asbestos or cement roof sheeting has a maximum life span of 15 years after which it begins to crumble and disintegrate. Hence after 15 years if you want to change your asbestos or cement roof then the only option is to remove the solar panels and mount them back again on a new roof which is a waste of time, money and effort. For this reason most solar installers, like Straton Solar, do not install solar panels on asbestos or cement roofs.”

What is a perfect roof for Solar Panels then?