Are sub-roof systems the answer?


With increased scrutiny on the state and repair of social housing, when looking at new roof specification, should landlords be thinking about a whole refit, or employing more cost-effective retrofit opportunities? Ardit Strica from Onduline Building Products asks the question

Several initiatives, including the recently launched ‘Make Things Right’ campaign spearheaded by the Department for Levelling up, Housing and Communities and the publication of the government’s Social Housing White Paper are precursors to a general tightening of the rules, regulations and standards associated with building construction and condition.

In particular, the Make Things Right initiative is set to place increased scrutiny on the safety and quality of social housing and ultimately make social housing landlords far more accountable for the state and repair of their properties in the eyes of the law, while giving tenants a greater voice to be able to complain about substandard housing.

Local authorities, housing associations and independent social housing landlords will be required to get to grips with a new era of oversight and reporting connected to the safety and condition of property construction and maintenance to remain compliant.

When it comes to housing maintenance, one important area that will need to be focused on is the roofing system, its specification, and its ongoing performance. As a vital element in efforts to ensure a property is up to the standards required, badly specified or performing roof systems can lead to ongoing and costly problems such as leaks, condensation and even poorly fixed tiles falling off. The new protections being given to social housing tenants mean that such issues will need to be attended to without delay.

Sub-roof systems

A sub-roof system is an additional and protective layer within the roof structure. It is used as a secured waterproofing layer, under the tiled roof, which acts as a barrier against potential leaks.

The fitting of a sub-roof system offers an ideal solution for making a roof completely watertight without having to completely renovate and buy new tiles, saving time and money.

There are different types of sub-roof systems. Flat sub-roofs are typically developed with non-breathable felt, which can be prone to a higher risk of moisture being trapped beneath the membrane thereby rotting the timber underneath.

More recently, corrugated sub-roof systems have been developed, offering greater protection and advanced longevity of materials. Due to the corrugations within the sub-roof, there is increased ventilation and airflow both above and below the sheet; tile battens positioned above the corrugations allow moisture to drain to the eaves which, with the enhanced ventilation, maintains excellent moisture control within the cavity.

What are the benefits of a sub-roof system for landlords?

As the sub-roof system acts as the main waterproofing element of a roof, it means that the original aesthetics of a building can be preserved. Existing tiles can be re-used, or reclaimed tiles, which can save on cost and time, as well as reducing the carbon footprint. This ensures that the traditional look and feel of the properties remains the same.

Integrating a sub-roof system provides an extra guarantee and protection should there be any cracked or broken tiles, a low pitch or incorrect fitting of tiles, as well as giving the option of using more cost-effective reclaimed tiles. The increased ventilation and performance this offers means that the roofing material will remain in good condition for longer.

The management of moisture and condensation within buildings has long been recognised as an important aspect of ensuring the longevity of a building’s fabric, by using a sub-roof system, landlords can hopefully not only save money and improve the aesthetics of their buildings, but also make the most of a maintenance-free roofing solution for years to come.

Ardit Strica is technical manager at Onduline Building Products