Watertightness

 

Sealing conditions:

The watertightness plane in the wall thickness is located in the inner structural wall (no cladding to ensure watertightness of external face).

Construction provisions ensure that any water or condensation that infiltrates into the lower part of the wall is drained outside. At the base of the superstructure, provisions are made to install a sealing strip (bituminous strip in accordance with standards NF EN 14967 and NF EN 12310-1 or PVC) fitted on internal face on insulation side, with a minimum height of 10 cm, minimum cover of 20 cm and installation of a weephole. A rigid plastic pipe with a minimum internal diameter of 30 mm is installed a maximum of every two meters.

 

        

 

Detailed illustration of foot of GBE wall:

 

 

 

Detailed illustration of foot of GBE wall if wall base is less than 1 m:

 

 

Detailed illustration of underground walls:

 

If cutting is performed on external face, seals are installed to prevent any infiltration. These seals are composed of a category 1 SNJF sealant, low modulus elastic, on joint. The width of the seals (ej) must comply with the following minimum dimensions (factor 4 takes account of the fact that seal deformation must be limited to 1/4 of its thickness).

ej ≥ 4.10-5 x ΔT x Lmax​

Where ΔT = max (50-T0 ; T0 30);       T0 : application temperature

In the event of seismic loading, the thickness of any seals could be increased as a function of the structure design.

 

 

 

Horizontal seal on outer skin:

If outer joinery and woodwork is included in the design, a method of draining any infiltration water is installed in its upper part.

 

Illustration of upper cross beam in outer joinery and woodwork:

 

Illustration of upper cross beam in outer joinery and woodwork - roller shutter:

 

Illustration of upper cross beam in outer joinery and woodwork: with sub-frame:

 

Any provisions for installing external windows or doors in GBE walls must comply with the provisions set out in NF DTU 36-5 P1-1 and P1-2. The joinery and woodwork must be fixed on the internal face and must be designed so that it does not touch the expandable outer skin. A continuous watertight seal must be installed between the door frames and the concrete faces.

 

 

Weather-exposed wall heads are protected against water infiltrations by a cap (on the top of the acroterion) that covers the entire thickness of the wall, attached to the structural internal face only. A small layer of non-reinforced concrete can be applied to the insulation section to protect it during the preliminary phase (i.e. pending the installation of the cap).

 

Protection of wall head with open height and aluminium cap/Protection of wall head with fully closed height and aluminium cap:

Watertightness complex solutions for nearly flat roofs: (* dimensions to be defined in accordance with the DTU (French codes of practice in the building industry) and thermal coefficient).