Polyurethane Systems for building and industry

Renovation of metal roofs

Metal roofs usually require renovation and waterproofing due to a multitude of factors, such as corrosion, high expansion and contraction over time (resulting in loosening of fastenings and cracks in joints and seals) or condensation and leaks in the waterproofing in difficult areas, in joints and unions (such as interior guttering, skylights, etc.).



The added value of the spaces under roofs

Due to the scant buildability and the value that each square meter supposes for both builders and residents, being able to take advantage of all the floors of a building is a point of interest. For this reason, solutions are sought so that attic spaces under roofs offer the maximum possible interior comfort.

Traditionally, these spaces were not considered habitable and they were mainly used to store both tools and food. To ensure that these spaces have adequate comfort points for their habilitability, it is necessary to carry out a renovation of the roof in those places where it can achieve the necessary insulation and waterproofing.



A renovation for each type of roof

Something to take into account is the diversity of types of roofs that we might have to renovate: flat or leaning; metal or wood; with previous isolation or without isolation; etc. After analyzing the type of roof, we also have to consider its situation, if it has been renovated, if it presents structural problems or if it does not have any type of thermal insulation.

Roofs with structural problems require more complex actions in their framework (beams, rafters, boards...). It is always advisable to carry out a preliminary study to contemplate the possibility of renovating the existing structure, rather than making a completely new one.

If the roof has been previously renovated or modified (extensions, change of roofing material), we must bear in mind that changes in geometry might have occurred due to the settlement of new loads. A common practice in cases of ancient renovations was to fill the space between the roof framing with tiles or bricks.


Roofing materials, such as tiles, have been subject to wear in their fixing points to the rest of the structure, which puts the whole at risk both structurally (loose pieces that drag others) and from a point of view of insulation and waterproofing (water and other environmental agents have easier access to the framework).

In terms of insulation and waterproofing, they may exist or not and, if they do, they might be worn out by the widespread use of insulating materials that are not resistant to the passage of time and the wear and tear of waterproofing solutions. 


Example of metal roof renovation in Hondarribia




For the renovation of the metal roof, ATERKI proposed a polyurethane system projected by polyurethane membrane and polyurethane foam. The objective of the action was to eradicate the problems of leaks and water entrance as well as to improve the insulation of the roof. In addition, the work required a short deadline (2 weeks).

The metal roof renovation in Hondarribia (Gipuzkoa) was carried out by projection of ATK ROOF high density polyurethane foam. Afterwards the hot polyurethane ATK COAT was applied and the highly resistant to UVA ATK TOP red final layer. The client was very satisfied with the system's performance (durability, speed ...) as well as the aesthetic result.

Thanks to this system, we have managed to improve the thermal insulation of the roof and waterproof it in a record time and at a low economic cost.

More information on Aterki's website.


Would you like to learn more about our waterproofing system for roofs and other surfaces? Read our article Polyurethane system for roof waterproofing with ETA or download the documents below. You will receive the product factsheet, the ETA document and a related success story:

Urespray P-500 for waterproofing

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