planning:refurbishment_with_passive_house_components:airtightness:step-by-step_retrofit_-_airtightness_concept
Differences
This shows you the differences between two versions of the page.
Next revision | Previous revision | ||
planning:refurbishment_with_passive_house_components:airtightness:step-by-step_retrofit_-_airtightness_concept [2015/06/15 12:41] – created mschueren | planning:refurbishment_with_passive_house_components:airtightness:step-by-step_retrofit_-_airtightness_concept [2015/08/04 18:05] (current) – kdreimane | ||
---|---|---|---|
Line 1: | Line 1: | ||
\\ | \\ | ||
====== Step-by-step retrofit: Airtightness concept ====== | ====== Step-by-step retrofit: Airtightness concept ====== | ||
- | + | {{:picopen:iee_.png?nolink |}} [[http:// | |
- | {{:picopen:newco-funded-iee-horiz.jpg?250}} [[http:// | + | |
**Author: Soeren Peper** | **Author: Soeren Peper** | ||
Line 12: | Line 11: | ||
For the Tevesstrasse project in Frankfurt am Main (multi-storey building with a total of 53 apartments), | For the Tevesstrasse project in Frankfurt am Main (multi-storey building with a total of 53 apartments), | ||
- | [{{ :playground: | + | [{{ :picopen: |
The importance of developing a concept for airtightness at an early stage of step-by-step modernisation will be explained here using an example. | The importance of developing a concept for airtightness at an early stage of step-by-step modernisation will be explained here using an example. | ||
Line 20: | Line 19: | ||
The detached house in Zellingen near Würzburg (Bavaria) was built in 1959. The size of the heated living area is 126 m². The first modernisation step took place in 1999 with extensive refurbishment of the roof, window replacement, | The detached house in Zellingen near Würzburg (Bavaria) was built in 1959. The size of the heated living area is 126 m². The first modernisation step took place in 1999 with extensive refurbishment of the roof, window replacement, | ||
- | [{{ :playground: | + | [{{ :picopen: |
The roof area of the building was timber-cladded on the inside. This was also the reason why the decision for insulation on the roof was made for the roof renewal in 1999. This measure could be carried out completely from the outside without any problems. A concept for airtightness was not developed at the time, and the subject of airtightness was not considered any further. The aluminium-coated insulation panels were laid using a tongue-and-groove system without any other airtight sealing between these. Since airtightness was not tested after the installation, | The roof area of the building was timber-cladded on the inside. This was also the reason why the decision for insulation on the roof was made for the roof renewal in 1999. This measure could be carried out completely from the outside without any problems. A concept for airtightness was not developed at the time, and the subject of airtightness was not considered any further. The aluminium-coated insulation panels were laid using a tongue-and-groove system without any other airtight sealing between these. Since airtightness was not tested after the installation, | ||
- | [{{ :playground: | + | [{{ :picopen: |
The subject of airtightness became relevant with the next modernisation step in the year 2014. No changes were planned for the already renewed roof. In order to improve airtightness of the roof space, the timber cladding of the roof area was almost entirely removed on the inside. The aluminium-coated insulation panels served as the airtight layer. An attempt was made to seal the joints between the panels using adhesive tape and a sprayed-on compound. | The subject of airtightness became relevant with the next modernisation step in the year 2014. No changes were planned for the already renewed roof. In order to improve airtightness of the roof space, the timber cladding of the roof area was almost entirely removed on the inside. The aluminium-coated insulation panels served as the airtight layer. An attempt was made to seal the joints between the panels using adhesive tape and a sprayed-on compound. | ||
However, sealing could not be implemented at the regularly-occurring points where the insulation panels rested on the rafters because the panels could not be raised. All these points represented leaks. The attempt to seal the panels all around alongside the rafters (on both sides) significantly extends the sealing surface by several times. In addition, the problem was shifted from the annexe and entrance area to the inaccessible connection points at the eaves, partly at the roof ridge and the junction of the main roof with the roof of the entrance porch. The leakage area could be reduced through work involving a lot of time and resources, but permanent and adequate airtightness could not really be achieved in this way. | However, sealing could not be implemented at the regularly-occurring points where the insulation panels rested on the rafters because the panels could not be raised. All these points represented leaks. The attempt to seal the panels all around alongside the rafters (on both sides) significantly extends the sealing surface by several times. In addition, the problem was shifted from the annexe and entrance area to the inaccessible connection points at the eaves, partly at the roof ridge and the junction of the main roof with the roof of the entrance porch. The leakage area could be reduced through work involving a lot of time and resources, but permanent and adequate airtightness could not really be achieved in this way. | ||
The following figures show the leaks and the extremely complicated efforts made for sealing, which were only partially successful. | The following figures show the leaks and the extremely complicated efforts made for sealing, which were only partially successful. | ||
- | [{{ : | + | [{{ picopen: |
- | [{{ :playground: | + | [{{ :picopen: |
Right: elaborate sealing of the floor in the tip of the roof slope plus additional poured gypsum plaster. Photos © Passive House Institute}}] | Right: elaborate sealing of the floor in the tip of the roof slope plus additional poured gypsum plaster. Photos © Passive House Institute}}] | ||
Double floors with openings towards the attic existed in some attic areas. At negative pressure, massive air flows passed through these openings into the attic. The point of entry on the outside was inaccessible or could not be ascertained. Supposedly this was the edge of the aluminium covered insulating panels at the eaves. As an effort was made to seal this tapered area at the transition of the attic floor to the roof from inside the roof area using boards etc. (Figure 5 / right), there was now increased air flow through this empty space. After this fault had been localised, an attempt was made to seal this leak using boards here as well (Figure 6). However, this was not completely possible on account of the interruption of the leakage surface due to the roof rafters. | Double floors with openings towards the attic existed in some attic areas. At negative pressure, massive air flows passed through these openings into the attic. The point of entry on the outside was inaccessible or could not be ascertained. Supposedly this was the edge of the aluminium covered insulating panels at the eaves. As an effort was made to seal this tapered area at the transition of the attic floor to the roof from inside the roof area using boards etc. (Figure 5 / right), there was now increased air flow through this empty space. After this fault had been localised, an attempt was made to seal this leak using boards here as well (Figure 6). However, this was not completely possible on account of the interruption of the leakage surface due to the roof rafters. | ||
- | [{{ :playground: | + | [{{ :picopen: |
Had a concept for airtightness been developed at an early stage, the focus would have had to be on the sealing of the roof area together with the connections to the airtight layer of the lower part of the building (existing exterior plaster). Various solutions would have been considered; a concept with the least possible penetrations should always be selected. | Had a concept for airtightness been developed at an early stage, the focus would have had to be on the sealing of the roof area together with the connections to the airtight layer of the lower part of the building (existing exterior plaster). Various solutions would have been considered; a concept with the least possible penetrations should always be selected. | ||
In general, it is challenging when the airtight layers of different areas cannot simply be directly joined with each other. The connection of the roof area to the airtight layer of the walls of the room below – as in the present example - is typical. In such cases, good airtightness values often cannot be expected. | In general, it is challenging when the airtight layers of different areas cannot simply be directly joined with each other. The connection of the roof area to the airtight layer of the walls of the room below – as in the present example - is typical. In such cases, good airtightness values often cannot be expected. | ||
- | [{{ :playground: | + | [{{ :picopen: |
A third solution that is possible is to shift the airtight layer to the outside of the building. This can be done by inspecting and reinforcing of the old plaster if necessary, or by applying filler. However, this only makes sense if thermal insulation is applied afterwards as soon as possible, in order to protect this layer permanently from thermal stresses (formation of cracks). This airtight layer on the old exterior surface must then be consistently connected at all relevant points (base point of the building and roof to attic transition). | A third solution that is possible is to shift the airtight layer to the outside of the building. This can be done by inspecting and reinforcing of the old plaster if necessary, or by applying filler. However, this only makes sense if thermal insulation is applied afterwards as soon as possible, in order to protect this layer permanently from thermal stresses (formation of cracks). This airtight layer on the old exterior surface must then be consistently connected at all relevant points (base point of the building and roof to attic transition). | ||
Line 45: | Line 44: | ||
In the building there was an installation shaft which connected the basement with the attic floor (see Figure 8). Cables passed through this shaft and since the modernisation, | In the building there was an installation shaft which connected the basement with the attic floor (see Figure 8). Cables passed through this shaft and since the modernisation, | ||
- | [{{ :playground: | + | [{{ :picopen: |
In practice, this was not easy to do because of restricted accessibility and the different materials etc. Pouring with thin plaster or expanding mortar proved to be a good solution (Figure 9). Before using this, the shaft had to be stuffed with construction foam so that the plaster or mortar did not drain away downwards, and a plug was formed. All cavities and spaces as well as the areas between cables and wires are filled completely due to the thinness of the plaster. | In practice, this was not easy to do because of restricted accessibility and the different materials etc. Pouring with thin plaster or expanding mortar proved to be a good solution (Figure 9). Before using this, the shaft had to be stuffed with construction foam so that the plaster or mortar did not drain away downwards, and a plug was formed. All cavities and spaces as well as the areas between cables and wires are filled completely due to the thinness of the plaster. | ||
- | [{{ :playground: | + | [{{ :picopen: intersection_of_two_pipes_and_cables.png? |
- | [{{ :playground: | + | [{{ :picopen: basement_shaft_with_solar_lines_and_cables.png? |
In another area of the basement, there was a second shaft end with more lines towards the first floor (Figure 11). The same situation existed here with reference to airtightness. | In another area of the basement, there was a second shaft end with more lines towards the first floor (Figure 11). The same situation existed here with reference to airtightness. | ||
When preparing the concept for airtightness, | When preparing the concept for airtightness, | ||
- | [{{ :playground: | + | [{{ :picopen: |
A typical problem arising during modernisation is the lack of clarity regarding the course of the airtight layer. In a rough concept the " | A typical problem arising during modernisation is the lack of clarity regarding the course of the airtight layer. In a rough concept the " | ||
- | [{{ :playground: | + | [{{ :picopen: |
\\ | \\ | ||
==== Airtightness measurements ==== | ==== Airtightness measurements ==== | ||
Line 61: | Line 60: | ||
The first measurement was carried out for testing the sealing work. This revealed that massive leakages existed and some points had not been sealed or were inadequately sealed, or had been sealed at the wrong places. The main point of leakage was localised above the entrance area at the transition to the roof. | The first measurement was carried out for testing the sealing work. This revealed that massive leakages existed and some points had not been sealed or were inadequately sealed, or had been sealed at the wrong places. The main point of leakage was localised above the entrance area at the transition to the roof. | ||
- | [{{ :playground: | + | [{{ :picopen: |
Due to the low airtightness of the building during the first Blower Door measurement (n< | Due to the low airtightness of the building during the first Blower Door measurement (n< | ||
The complicated sealing work was tested during the second measurement which took place two weeks later. It turned out that numerous leaks still existed despite significant improvements. The measured value was reduced by almost a half. In particular, the leaks discussed previously were identified as the biggest source of leakage: | The complicated sealing work was tested during the second measurement which took place two weeks later. It turned out that numerous leaks still existed despite significant improvements. The measured value was reduced by almost a half. In particular, the leaks discussed previously were identified as the biggest source of leakage: | ||
Line 83: | Line 82: | ||
Using this example case and the results of the airtightness measurements and leak detection, the need for a comprehensive concept for airtightness is clearly evident. | Using this example case and the results of the airtightness measurements and leak detection, the need for a comprehensive concept for airtightness is clearly evident. | ||
- | {{ :playground: | + | [{{ :picopen: |
\\ | \\ | ||
Line 91: | Line 90: | ||
==== Literature ==== | ==== Literature ==== | ||
- | |[Feist/ | + | |[Feist/ |
- | |[Kaufmann et al. 2009]|Berthold Kaufmann; Søren Peper; Rainer Pfluger; Wolfgang Feist: Sanierung mit Passivhaus-komponenten, Planungsbegleitende Beratung und Qualitätssicherung Tevesstraße Frankfurt a.M., Bericht im Auftrag des Hessischen Ministeriums für Wirtschaft, Verkehr und Landesentwicklung, | + | |[Kaufmann et al. 2009]|Berthold Kaufmann; Søren Peper; Rainer Pfluger; Wolfgang Feist: Sanierung mit Passivhaus-Komponenten, Planungsbegleitende Beratung und Qualitätssicherung Tevesstraße Frankfurt a.M., Bericht im Auftrag des Hessischen Ministeriums für Wirtschaft, Verkehr und Landesentwicklung, |
|[Peper/ | |[Peper/ | ||
\\ | \\ |
planning/refurbishment_with_passive_house_components/airtightness/step-by-step_retrofit_-_airtightness_concept.txt · Last modified: 2015/08/04 18:05 by kdreimane