The 100% mineral ITE system at the heart of a rehabilitation of 164 housing units

This system is the result of a close collaboration between Ytong - world leader in aerated concrete - and Keim - exclusive manufacturer of 100% mineral paints. Two companies that share the same product ethics with the aim of creating a tailor-made IHE solution that is consistent with new thermal regulations.

The quality of the system components offers benefits in terms of respect for the environment, thermal insulation, protection against humidity and fire resistance. It is applicable on any new masonry or on any facade to be renovated.

Keim XPor® a complete ITE system chosen in more than 115 sites since 2012, ie 27 m000 of installed ITE.

The success of this project

The success of this project depends on several parameters:

• The quality of the partnership between Ytong and Keim was characterized by very good communication and responsiveness between the technical services (Design and Development Office).
• The precise identification of the requirements and constraints of the project made it possible to validate a tailor-made technical solution.
• Training provided upstream of the site and in situ, for the installation company:
  • A specific training course “Thermal Insulation by the Exterior for new construction and renovation with the XPor® process” was organized by Ytong, in one of its training centers.
  • Training and extensive technical control of the progress of the work were implemented by Keim's technical and sales department, throughout the project. A follow-up site very appreciated by the architects.

The building site

Located in Nantes, the site concerns the rehabilitation of a Gendarmerie barracks comprising 164 collective public housing units spread over 12 buildings.

A total of 8 m100 of Keim XPor® were deployed on a concrete support and on a filling wall in a block with distributed insulation, to cover the asbestos sheets under the bays.

The combination of a Multipor insulating panel manufactured by Ytong and a Keim Soldalit® mineral finish makes it a powerful solution. On this site, almost 36 Multipors were used, and more specifically YTONG blocks 350 cm thick with an R of 16 m3,55.K / W and 2 cm with an R of 20 , 4,40 m2.K / W.

Multipor is an insulating panel made of lightweight aerated concrete, 100% mineral (sand, lime, cement and water), rigid, fiber-free and VOC-free. With its honeycomb mineral structure, it lets buildings breathe. It has a very high fire resistance (classified A1 according to standard EN-13501-1).

It reinforces the protection of the occupants of a building against fire and the toxic gases given off in the event of fire. For example, the Multipor insulating panel provides fire protection for 4 hours, for the 6 cm thick block.

The major complexity of this project lies in the solution to find to overcome the problem of asbestos panels to be insulated in the same way as the rest of the facade, without removing asbestos. To achieve the desired result, the recommended solution is to fill the sills under the windows, with Compact 20 blocks (Ytong cellular concrete with a thickness of 20 cm).

The use of this process thus makes it possible to avoid any phase of asbestos removal, which requires restrictive and costly technical provisions.

This project, beyond its scope, is based on two specific constraints:

• The main constraint remains in the dark shade required by the architect. To meet the specifications, the 100% mineral ITE system, made up of the Soldalit mineral finish - Coolit technology, was essential. It is a paint that allows the reduction of the heating of facades linked to solar radiation.
• On the other hand, the project had to respect the client's specifications, which required a smooth appearance of the plaster. It is often a criterion retained to keep a clean facade longer, because the facades of very structured appearance get dirty quickly. The finish of the Light XPor® mortar gives a fine floated finish, in accordance with the client's needs.

This ITE system is particularly suitable for this type of site because it actively contributes to fire protection thanks to its non-combustible components.

• MULTIPOR: class A1 (according to DIN EN 13501-1)
• SOLDALIT: M0 on M0 (Euroclass, class A2 - s1 - d0, according to NF EN 13501-1)

Keim XPor® system

The Keim XPor® Exterior Thermal insulation system consists of:

• 100% mineral insulation board certified Acermi and manufactured by Ytong. Multipor has the following dimensions: 600 x 390 mm and is available in 8 thicknesses from 6 to 20 cm.
• XPor® Light Mortar which serves as a mortar, a base coat and a finishing plaster (a very practical and economical triple function).
• XPor® frame, treated fiberglass frame.
• of EJOT STRU 2G anchors. The system is always glued / pegged.
• a Keim Soldalit® Grob underlayment and a Keim Soldalit® mineral finish guaranteeing color stability over time and ensuring good breathing of the system.

The site of all records

• Works duration : 18 months for the application of the ITE system on the 8 m100
• Type of building: 164 apartments spread over 12 buildings
• Keim XPor® total area: 8 100 m2
• Multipor: 36 panels
• XPor light mortar: 81 000 kg
• XPor reinforcement (reinforcement mesh): 155 rolls
• EJOT STR U2G screw anchor: 46 pegs

Simple, fast and economical implementation

The renovation of collective housing on occupied sites cannot be improvised. Thus, for the renovation of this project, the construction system was installed most of the time with lifting equipment.

With its optimized dimensions in 600 x 390 mm and its lightness (115 kg / m3), the Ytong Multipor insulation panel remains the ideal solution for easy handling and simple to implement.

The installation of this product requires key steps, which guarantee the performance of the work: the gluing of the insulating panel, the anchoring with the EJOT STRU 2G anchors, the application of a uniform layer of light mortar with masking of the weft, and the application of mineral finish plaster.

In addition, the reinforced base layer and the finishing plaster are made with the same material (Light Mortar XPor®), saving time and money.