When the facade comes to an end a air tightness test must be done to assure that the envelope is closed. As this project is BBC & HQE it has many constraints and for example only the tolerance of 1m3 of air flow for the test done at 4 Pa for the surface of 190m². This test is done in depression. The gas is spread at exterior for the measurements and since the volume is in depression the volume of gas entered in the test room is observed from inside. Because the flow of the wind at 50Pa is noticebale this test is done starting from this point for varying pressure in the difference of 10 Pa that means at 50Pa, 40Pa, 30Pa, 20Pa and 10Pa. The result obtained is extrapolated for 4Pa as required by the french laws to find the volume of air entered in the envelope. However generally in Europe the value at 10Pa is accepted.
Below are some photos of this test.
During explanation of the procedures of test and objective:
From the test done, it is obtained 1.9m3 which is almost double then the target. So the thermal bridge has to be identified in order to treat for efficiency of the building envelope.
A high volume of air transfer was found across the concrete bloc, concrete blocs are very weak insulator.
Also the reservations for wire are also reasons for the air circulation, so the reservations must be enclosed properly to avoid the air transfer.
As the windows covered maximum of surface areas and a remarkable air transfer is observed from wondows. A treatement has to be done for these windows and test must be done in order to obtain the objective desired (minimum : 1m3 )
As the objective of project is to gain title of “high quality environmental” and “low energy consummation” there are many constraints since the conception till the end of the project. The façade in this project is of aluminium triple glasses and the blocs made by cement and glass. This facade is done in two phases. In the first phase the aluminium blocs with triple glasses layer is implanted. These blocs are fabricated in the factory and it is placed using the fixing lugs. When the airtight/watertight is done then the blocs made by cement and glass (composite ciment verre; CCV) is implanted. As I explained in the previous topics the medium of implantation of facade is bi-mâts, a motorized platform of work standing in two metallic pillars.
In the first phase the prefabricated aluminium blocs are implanted in the fixing lugs prepared for this. The fixing lugs must be on the appropriate height and the escapement between them must be correct as the blocs are prefabricated. The position of those blocs are found by the geometrical lines drawn in the project and the need of the blocs. However a adjusting screw is integrated on the lugs for the simplicity of the adjustment.
The blocs are either implanted by the work platform, nacelle or by using crane.
These blocs are fixed with angles at corners to made airtight and watertight. The small openings are then closed by silicon. windows are then put in place and finishing touch of facades is done.
If the blocs are implanted with accuracy the second phase starts:
For the second phase the platform is adjusted to leave enough space to implant CCV shells. These blocs are also prefabricated and implanted in the same way as aluminium blocs. First the fixing lugs are implanted with accuracy and the implantation starts.
The pillars must be isolated to avoid the thermal bridge.
Once the blocs are implanted, the adjust must be done to have the predefined spacing between them. Below are some photos before adjusting.
Once the blocs are properly fixed the curtain is fixed on the openings left for this purpose. Then the finishing touch is given to have the good finishing of the facade.
When the surface is treated for impermeability to be sure that is really impermeable a test of impermeability of water is mandatory. For this purpose the water exit are closed temporarily and the water of sufficient height is put for the test. the filled water is colored with florescence powder in order to verify if the infiltration viewed is from the the surface in test.
Add of florescence for the test:
This water remains for some day and then the control of impermeable is done. In the control the company who treated the surface is present along with the construction company and the member of sub-contractors for garden etc.
If the infiltration is observed then the sub-contractor company who treated the impermeability finds the area of infiltration and it treats the surface.
Then retest is done in the same way with the another florescence color to verify the infiltration. If the surface is impermeable the verbal process of receiving support is delivered to the executing company by the sub-contractor who treats the surface.
click here for the sample of process verbal of support reception
In this topic I am going to describe how the modern garden is made when there exist a building compartiment underneath. For the plane garden there must be no problem for the level of soil. But in this project we have a discontinous surface as in picture below.
I’l talk later ways to overcome this uncontinuous surface. In order to make the garden firt we applied the DELTERAXX just above the concrete surface already treated for impermeability, this material permits infiltration of water from on side (top) and is impermeable the other side (bottom). The water can go down and flow to the exit point.
Then extruded polystyrene (polystyrène extrudé ) is put on to gain the height of the soil which is quite expensive for quality soil as in the photos:
It is then covered by thin layer partly permeable to leave only the water to infiltrate and to resist the solid materials this is geotextile materials.
Knowing the exact position of plant the two bed of iron bars are kept just below the plant in order to fix the plant with the ground.
When all these prepartion are made, the soil is put from above to an predefined height.
In order to hold the trees properly welded two layers of iron bars (square) of dimension 2mX2m are posed where there are plants. Then the plants are planted.