TRISO-TOITURE: Express waterproofing and airtightness of a Toulouse building roof

Following damage noted on the roof (infiltration, falling fascia boards, detached gutter, etc.), the SOGEA trustee in charge of this residence, made up of different buildings, called on the KHEOPS architectural firm to obtain an inventory. After an initial visit and the production of a CCTP, the firm mandated the SERBTP company to carry out repairs only on the roof overhang, taking into account the underside paneling and the aluminum gutter board as well as the installation of a zinc gutter.

Located in a listed area in the historic center of Toulouse, the renovation of the 1600 m2 roof of this building had to meet the expectations of the ABF (Architects of Buildings of France) in order not to distort the aesthetics of the building and preserve the historical identity of the district.

The initial objective was not to redo the insulation. However, SERBTP recommended taking advantage of the roof repair to integrate Actis Triso-Toiture reflective honeycomb insulation into the 900 m2 of two buildings in the residence that house attic apartments.

The latter replaces the compacted glass wool, installed between rafters and without rain protection, around forty years ago. Built as a truss, the other wing of the building did not require the installation of this type of insulation.

“The advantage of using Triso-Toiture was to remain within the thickness of the rafters and not to encroach on the living space of the apartments located under the attic and to generate additional work on the ceilings but also the electricity, plumbing, etc.” explains Olivier Devalland, SERBTP Site Manager.

Installed from the outside, without significantly raising the roof and without modifying the appearance of the building, the reflective cellular insulation Triso-Toiture from Actis consists of two complementary insulators implemented in such a way as to form an insulating and waterproof envelope:

• Triso Hybrid', honeycomb reflective insulation with integrated vapor barrier,
• Boost'R Hybrid, a breathable, flexible, reflective honeycomb under-roof insulation with an integrated HPV screen. It provides both insulation and a water vapor-permeable rain barrier (Sd < 0,35 m), allowing waterproofing to be achieved in a single operation.

"A first blanket of Triso Hybrid' was installed in a rack to use the space between rafters using the Actis ISOCLIP accessory. We take advantage of the depth of the rafter to bring the insulation to the lowest point and create a gap of unventilated air. On top, we stretched a second blanket of Boost'R Hybrid which acts as a rain screen and which also has the function, in the event of broken tiles, of draining water into the gutter or the gutter thanks to the installation of a zinc drip edge at the low point of the roof (according to DTU 40.29). The latter allows rainwater to flow between the Triso-Toiture insulation, right into the gutter." explains Olivier Devalland.

Regarding the installation of Triso-Toiture insulation, "It is fast, simple and efficient, considerable advantages for making the roof watertight and airtight in record time and avoiding any potential problems in the event of rain in the apartments located under the roof. Another advantage is that we do not need to cover the roof with a tarpaulin to ensure its waterproofing once the work day is over, which represents a lower cost for the client." adds the site manager. "Finally, the rolls are lightweight, making them easy to transport to the construction site. A roofer can carry under each arm, in a single trip, a roll of Triso Hybrid and one of Boost'R Hybrid to install 16 m2 of Triso-Toiture!" adds Mr. Devalland.

Featuring high performance, Triso-Toiture will allow the residents of this city center building to enjoy both winter and summer comfort since this insulation provides both:

• thermal insulation in winter thanks to high performance (R = 6,35 m².K/W),
• summer comfort thanks to reflective films returning up to 95% of infrared radiation,
• an effective reduction in noise pollution (up to -37 decibels of attenuation) greater than the requirements of the new acoustic regulations,
• water and air tightness according to the NF EN 1928 standards Method A and NF EN 12114.

In addition, Actis' Triso-Toiture is insensitive to humidity and its lightness ensures high resistance to settling, which allows it to maintain its mechanical characteristics and thermal performance over time. Certified NF EN ISO 22097:2023, Triso-Toiture is eligible for MaPrimeRénov' and other public aid schemes.