planning:refurbishment_with_passive_house_components:thermal_envelope:airtightness

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-[[http://​www.passivehouse-international.org/​index.php?​lang=de|{{:​picopen:​members_area_picture.png?​570}}]] 
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 ====== Airtightness in old buildings ====== ====== Airtightness in old buildings ======
  
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 ===== Testing the airtightness ===== ===== Testing the airtightness =====
  
-The airtightness of a building can be measured by means of an air pressure test (airtightness test or “blower door test”) which determines the overall remaining leakage of a building. ​ A fan is installed into a door or window to create a negative pressure in the whole house. The fan has a measuring device which gives the air flow rate for the pressure being tested. ​ Flow rates are recorded for pressure differences at several points between 10 and 70 Pascals (Pa) negative pressure. The value at 50 Pa is calculated from the range of readings. ​ The whole process is then repeated using a range of positive pressures.[[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[EN 13829] ]].\\+The airtightness of a building can be measured by means of an air pressure test (airtightness test or “blower door test”) which determines the overall remaining leakage of a building. ​ A fan is installed into a door or window to create a negative pressure in the whole house. The fan has a measuring device which gives the air flow rate for the pressure being tested. ​ Flow rates are recorded for pressure differences at several points between 10 and 70 Pascals (Pa) negative pressure. The value at 50 Pa is calculated from the range of readings. ​ The whole process is then repeated using a range of positive pressures [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[EN 13829] ]].\\
 \\ \\
 |{{ :​picopen:​blowerdoor_bild01_en_mit_logo.png?​300 }}|{{ :​picopen:​blowerdoor_bild02_en_mit_logo.png?​300 }}| |{{ :​picopen:​blowerdoor_bild01_en_mit_logo.png?​300 }}|{{ :​picopen:​blowerdoor_bild02_en_mit_logo.png?​300 }}|
-|//**Figure 1: Basic measurement setup for testing airtightness;​ [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper/​Feist/​Sariri 1999] ]].**//||\\+|//**Figure 1: Basic measurement setup for testing airtightness;​ [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Peper/​Feist/​Sariri 1999] ]].**//||\\
 \\ \\
 The negative and positive air pressure test results at 50 Pa are then averaged to give a single result, the leakage rate n<​sub>​50</​sub>​ at 50 Pascals. The units are air changes per hour, written 1/h or h<​sup>​-1</​sup>​. This is the flow rate at 50 Pa (average of negative and positive tests) in m³/h divided by the building air volume V<​sub>​L</​sub>​ in m³. A similar measure, q<​sub>​50</​sub>​ value with units m³/(m²h) uses the air pressure result per unit area of the building envelope A [m²]. The negative and positive air pressure test results at 50 Pa are then averaged to give a single result, the leakage rate n<​sub>​50</​sub>​ at 50 Pascals. The units are air changes per hour, written 1/h or h<​sup>​-1</​sup>​. This is the flow rate at 50 Pa (average of negative and positive tests) in m³/h divided by the building air volume V<​sub>​L</​sub>​ in m³. A similar measure, q<​sub>​50</​sub>​ value with units m³/(m²h) uses the air pressure result per unit area of the building envelope A [m²].
  
-Pressure test results of old buildings that have not been modernised are often in the range between 3 and 6 h<​sup>​-1</​sup>;​ however, much higher values are also acheived. Energy efficient buildings should reach values less than 1 h<​sup>​-1</​sup>;​ the target value for Passive Houses is <0.6 h<​sup>​-1</​sup>​. This high requirement is frequently fulfilled (see [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper 2000] ]]). Such excellent airtightness levels can also be achieved for modernised buildings if airtightness is considered from the very start. Some good examples of this are the well-documented refurbishment projects in Frankfurt a.M., Ludwigshafen and Nuremberg. In these complete refurbishments,​ values between 0.4 and 0.7 h<​sup>​-1</​sup>​ were measured ([[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Kaufmann/​Peper/​Pfluger/​Feist 2009] ]] [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper/​Feist 2008] ]] [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Darup et all 2005] ]]).+Pressure test results of old buildings that have not been modernised are often in the range between 3 and 6 h<​sup>​-1</​sup>;​ however, much higher values are also acheived. Energy efficient buildings should reach values less than 1 h<​sup>​-1</​sup>;​ the target value for Passive Houses is <0.6 h<​sup>​-1</​sup>​. This high requirement is frequently fulfilled (see [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Peper 2000] ]]). Such excellent airtightness levels can also be achieved for modernised buildings if airtightness is considered from the very start. Some good examples of this are the well-documented refurbishment projects in Frankfurt a.M., Ludwigshafen and Nuremberg. In these complete refurbishments,​ values between 0.4 and 0.7 h<​sup>​-1</​sup>​ were measured ([[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Kaufmann/​Peper/​Pfluger/​Feist 2009] ]] [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Peper/​Feist 2008] ]] [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Darup et all 2005] ]]).
  
-With professional planning and implementation of the airtightness measures using the appropriate materials, permanently high airtightness values of the building can be expected ​ ([[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper/​Kah/​Feist 2005] ]]).\\+With professional planning and implementation of the airtightness measures using the appropriate materials, permanently high airtightness values of the building can be expected ​ ([[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Peper/​Kah/​Feist 2005] ]]).\\
 \\ \\
  
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 This does not depend on the size of the building and can be used for comparisons between buildings or for comparisons before and after the modernisation. The actual heated volume of the building is the result of the heated living space multiplied by the clear room height. This does not depend on the size of the building and can be used for comparisons between buildings or for comparisons before and after the modernisation. The actual heated volume of the building is the result of the heated living space multiplied by the clear room height.
  
-The volume in a wall that results from the installation of a window or a door is not taken into account for the calculation of the building volume. For suspended ceilings only the clear measurement up to the suspended ceiling is considered. This always applies regardless of how airtightly the suspension has been carried out. Among other things, this stipulation according to [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[FliB 2002] ]] in addition to the [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[EN 13829] ]] standard facilitates the test in old buildings for which no detail plans are available.+The volume in a wall that results from the installation of a window or a door is not taken into account for the calculation of the building volume. For suspended ceilings only the clear measurement up to the suspended ceiling is considered. This always applies regardless of how airtightly the suspension has been carried out. Among other things, this stipulation according to [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[FliB 2002] ]] in addition to the [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[EN 13829] ]] standard facilitates the test in old buildings for which no detail plans are available.
  
 Beams, visible rafters etc. are not deducted. The actual size of the volumes under sloping ceilings etc. are taken into account. If there are staircases inside the airtight layer these are also added with their base area and clear height without considering the stairs themselves (i.e. as a simplification the volume of the steps is not subtracted from the building volume). Beams, visible rafters etc. are not deducted. The actual size of the volumes under sloping ceilings etc. are taken into account. If there are staircases inside the airtight layer these are also added with their base area and clear height without considering the stairs themselves (i.e. as a simplification the volume of the steps is not subtracted from the building volume).
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 The q<​sub>​50</​sub>​-value is more suitable for calculating the air transporting devices (fans) required for the test in large buildings. The q<​sub>​50</​sub>​-value is more suitable for calculating the air transporting devices (fans) required for the test in large buildings.
  
-The calculation for the envelope surface is given in [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[EN 13829] ]]. The envelope surface is the total area of all floors, walls and ceilings that enclose the volume (in a terraced house this includes the partition walls of adjacent houses). The areas below the ground level are also included. The “__interior__ dimensions through everything” are used for the calculation. The abutting face of integrated interior walls, ceilings, and floors are __not__ deducted, thus simplifying the calculation.\\+The calculation for the envelope surface is given in [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[EN 13829] ]]. The envelope surface is the total area of all floors, walls and ceilings that enclose the volume (in a terraced house this includes the partition walls of adjacent houses). The areas below the ground level are also included. The “__interior__ dimensions through everything” are used for the calculation. The abutting face of integrated interior walls, ceilings, and floors are __not__ deducted, thus simplifying the calculation.\\
 \\ \\
-|{{:picprivate:​n50_q50_engl_saeulen.png?​500}}|+|{{:picopen:​n50_q50_engl_saeulen.png?​500|}}|
 |//**Figure 2: Interrelation of the q<​sub>​50</​sub>​-value for 6 sample buildings of different sizes\\ (simple cuboid shapes of various dimensions) with a constant n<​sub>​50</​sub>​-value.**//​|\\ |//**Figure 2: Interrelation of the q<​sub>​50</​sub>​-value for 6 sample buildings of different sizes\\ (simple cuboid shapes of various dimensions) with a constant n<​sub>​50</​sub>​-value.**//​|\\
 \\ \\
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 ===== Basic principles for planning airtightness ===== ===== Basic principles for planning airtightness =====
  
-There are two central planning fundamentals for implementing an airtight building envelope (based on [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 1995] ]]):\\+There are two central planning fundamentals for implementing an airtight building envelope (based on [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Feist 1995] ]]):\\
 \\ \\
 ^1. The “pencil rule”: it must be possible to trace the airtight layer of the envelope in the plan (for each building section) using a pencil without lifting the pencil – except for any planned ventilation openings. ​  ^\\ ^1. The “pencil rule”: it must be possible to trace the airtight layer of the envelope in the plan (for each building section) using a pencil without lifting the pencil – except for any planned ventilation openings. ​  ^\\
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 ^2. There must be only one single uninterrupted airtight layer. ​ Leaks CANNOT be remedied by another airtight layer before or after the first one (e.g. double lip seals at windows, vestibule door behind the front door). ​ A comparison to illustrate this point: water won’t stop leaking from a bucket with a leak if the bucket is placed inside another bucket with a leak.   ^\\ ^2. There must be only one single uninterrupted airtight layer. ​ Leaks CANNOT be remedied by another airtight layer before or after the first one (e.g. double lip seals at windows, vestibule door behind the front door). ​ A comparison to illustrate this point: water won’t stop leaking from a bucket with a leak if the bucket is placed inside another bucket with a leak.   ^\\
 \\ \\
-Besides the basic principles, the following guidelines are helpful for successful planning of the airtightness – whether for a new construction or for a refurbishment of an old building (based on [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 1995] ]]):+Besides the basic principles, the following guidelines are helpful for successful planning of the airtightness – whether for a new construction or for a refurbishment of an old building (based on [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Feist 1995] ]]):
   * **simplicity**:​ in order to prevent any deficiencies in the workmanship,​ all construction details should be as simple to carry out as possible   * **simplicity**:​ in order to prevent any deficiencies in the workmanship,​ all construction details should be as simple to carry out as possible
   * preferably **large uniform** areas with a simple basic construction   * preferably **large uniform** areas with a simple basic construction
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 For **lightweight or mixed constructions**,​ chipboard, plywood, OSB boards and tempered wood fibreboards are used for the airtight layer. These are normally mounted on cross battens and the joints must be bonded or connected airtightly. Prefabricated foils, cardboard strips and adhesive tapes are available for this purpose. For **lightweight or mixed constructions**,​ chipboard, plywood, OSB boards and tempered wood fibreboards are used for the airtight layer. These are normally mounted on cross battens and the joints must be bonded or connected airtightly. Prefabricated foils, cardboard strips and adhesive tapes are available for this purpose.
  
-A reliable solution for lightweight constructions is the “double use” of the vapour barrier [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 1997] ]]. This is located on the inside of the load-bearing structure and is normally separated from the wall cladding on the inside by the lathing. This results in a gap which can be used for the building services installations. Another possibility is to position the vapour barrier immediately behind the interior cladding. Only diffusion-resistant materials can be used for vapour barriers so that airtightness can be ensured. The use of foils or reinforced building boards is common. If continuous polyethylene sheets are used (e.g. for wooden constructions such as rafter roofs), these should be applied on the inward side of the thermal insulation.\\+A reliable solution for lightweight constructions is the “double use” of the vapour barrier [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Feist 1997] ]]. This is located on the inside of the load-bearing structure and is normally separated from the wall cladding on the inside by the lathing. This results in a gap which can be used for the building services installations. Another possibility is to position the vapour barrier immediately behind the interior cladding. Only diffusion-resistant materials can be used for vapour barriers so that airtightness can be ensured. The use of foils or reinforced building boards is common. If continuous polyethylene sheets are used (e.g. for wooden constructions such as rafter roofs), these should be applied on the inward side of the thermal insulation.\\
 \\ \\
  
 ==== Linear airtight connections ==== ==== Linear airtight connections ====
  
-If basic airtight constructions have been chosen for the different building components, the airtight connections between the building components must also be carefully planned, because this is where significant leaks are often found later on. Even a compact single-family house with a simple layout can be used as an example: depending on the type of construction,​ there are 150 to 300 m of leak-prone component connections [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Zeller etc. 1995] ]]. It is obvious that this will greatly influence the overall airtightness of the building, therefore particular attention must be paid to these areas during the planning and implementation phases. For connections in particular, recourse should be taken to a few, easily implemented and reliably airtight details.+If basic airtight constructions have been chosen for the different building components, the airtight connections between the building components must also be carefully planned, because this is where significant leaks are often found later on. Even a compact single-family house with a simple layout can be used as an example: depending on the type of construction,​ there are 150 to 300 m of leak-prone component connections [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Zeller etc. 1995] ]]. It is obvious that this will greatly influence the overall airtightness of the building, therefore particular attention must be paid to these areas during the planning and implementation phases. For connections in particular, recourse should be taken to a few, easily implemented and reliably airtight details.
  
-In the publication [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper 2008] ]], it was explained that good planning for airtightness begins with the identification of the airtight layers of the building components. The following example is given there to illustrate this point.+In the publication [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Peper 2008] ]], it was explained that good planning for airtightness begins with the identification of the airtight layers of the building components. The following example is given there to illustrate this point.
  
 === Example: Installation of a window or door frame in an external masonry wall === === Example: Installation of a window or door frame in an external masonry wall ===
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 **III.** A plaster end-strip which is applied at a distance of ≥ 8 mm from the window frame, creating a defined groove between the plaster strip edge and the frame. Tape (e.g. consisting of paper or fabric) is inserted into this groove to prevent the joint filler from sticking to the brickwork of the reveal. Then the space between the plaster end-strip and frame is filled with the flexible joint filler (silicone or acrylic filler) so that it adheres to the plaster end strip and the frame (two-flank bonding).\\ **III.** A plaster end-strip which is applied at a distance of ≥ 8 mm from the window frame, creating a defined groove between the plaster strip edge and the frame. Tape (e.g. consisting of paper or fabric) is inserted into this groove to prevent the joint filler from sticking to the brickwork of the reveal. Then the space between the plaster end-strip and frame is filled with the flexible joint filler (silicone or acrylic filler) so that it adheres to the plaster end strip and the frame (two-flank bonding).\\
 \\ \\
-|{{ :picprivate:​bild_1bis4_en.png?​500 }}| +|{{ :picopen:​bild_1bis4_en.png?​500 ​ |}}| 
-|//**Figure 3: The possibilities (see above (I) to (III)) for a permanently airtight\\ connection of the window frame in plastered solid masonry\\ (adapted from [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper/​Feist/​Sariri 1999] ]]).**//|\\+|//**Figure 3: The possibilities (see above (I) to (III)) for a permanently airtight\\ connection of the window frame in plastered solid masonry\\ (adapted from [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Peper/​Feist/​Sariri 1999] ]]).**//|\\
 \\ \\
-Based on the basic principle given in the example described in [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper 2008] ]], it becomes clear that **switching the location of the airtight layer** between the inside and the outside of the supporting structure should be avoided as far as possible. If this rule is adhered to, connections between similarly constructed components (e.g. solid external wall to solid ceiling or solid interior wall, or lightweight external wall to lightweight roof) will be less complicated in terms of planning. Connections between lightweight and solid construction methods require particular attention.\\+Based on the basic principle given in the example described in [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations#​Literature|[Peper 2008] ]], it becomes clear that **switching the location of the airtight layer** between the inside and the outside of the supporting structure should be avoided as far as possible. If this rule is adhered to, connections between similarly constructed components (e.g. solid external wall to solid ceiling or solid interior wall, or lightweight external wall to lightweight roof) will be less complicated in terms of planning. Connections between lightweight and solid construction methods require particular attention.\\
 \\ \\
 ===== Penetrations of the airtight layer ===== ===== Penetrations of the airtight layer =====
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 ====== See also ====== ====== See also ======
  
-[[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations|Special features of modernisations]]+[[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness:​special_features_in_modernisations|Special features of modernisations]] ​ ​{{:​picopen:​members_only.png?​nolink&​20|}}
  
-[[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​improving_thermal_bridges_and_airtightness_in_existing_buildings|Improving thermal bridges and airtightness in existing buildings]]+[[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​improving_thermal_bridges_and_airtightness_in_existing_buildings|Improving thermal bridges and airtightness in existing buildings]] ​
  
-===== Special features of modernisations ===== 
  
-It has already been analysed in [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]] that reflecting on the requirements given above for modernisations of old buildings quickly reveals the problems related to this: in old buildings there is hardly ever a continuous, easy-to-access layer through all building components, which can be used for creating the new airtight layer (see //**Figure 4**//). In modernisations of old buildings, if there are interruptions in the airtight envelope, one can hardly expect the excellent results relating to the n<​sub>​50</​sub>​ values that are always achieved in the Passive House. Therefore it should be considered how this objective can be achieved with old buildings. For old buildings, each case must be examined and determined individually. When deciding in favour of a concept, it is important to keep the whole building with all its aspects in mind. Some aspects will be examined in detail below.\\ 
-\\ 
-|{{ :​picprivate:​nuernberg_luftdichte_linie.png?​400 }}| 
-|//**Figure 4: A continuous airtight envelope in an old building?\\ Where exactly can it be located? (Source: [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]])**//|\\ 
-\\ 
-In solid constructions requiring modernisation,​ there are often wood beam ceilings which interrupt the airtight layer – which is usually the interior plaster. //**Figure 5**// shows the leak from/to the outside near the wood beam ceiling for the airtight layer on the inside on the left side. With an unplastered masonry wall in the area of the floor construction,​ it can be expected that this will not be sufficiently airtight. On the right side in the area of the wood beam ceiling, the leak towards the room below (e.g. basement), which is not located within the airtight volume, is shown. **//Figure 6//** shows an unplastered area in an exposed floor construction.\\ 
-\\ 
-|{{ :​picprivate:​refurbishment_airtightness_fig_5-a.jpg?​277 }}|{{ :​picprivate:​refurbishment_airtightness_fig_5-b.jpg?​300 }}| 
-|//**Figure 5: Problematic area in an airtight layer on the inside: the wood beam ceiling;\\ subsequent sealing is only possible by including the planks at the edge – with\\ interior insulation this is vital (Source: [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]]).**//​||\\ 
-\\ 
-|{{ :​picprivate:​ensan_r0011377_phi.jpg?​500 }}| 
-|//**Figure 6: Absence of interior plaster in the exposed area of the wood beam\\ ceiling in a modernisation project [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper 2005] ]].**//|\\ 
-\\ 
-During the complete refurbishment of a building built in the Wilhelminian style, some of the beam heads had to be replaced. For this reason the floor near the external walls of the rooms had to be opened up. In such cases, it is possible to create the uninterrupted airtight layer all along the inside of the exterior facade (see //**Figure 7**//). In this case, interior insulation was applied. The airtight layer is only interrupted by the beam heads, each of which had to be connected with the airtight layer. It is an objective of the 3ENCULT Project to find simple and practicable solutions for this.\\ 
-\\ 
-|{{ :​picprivate:​ensan_r0010335_phi.jpg?​500 }}| 
-|//**Figure 7: completely exposed floor construction along the exterior facade during\\ a refurbishment. The window and the balcony door of the storey below can be\\ seen. In this case, it was possible to create the airtight layer (here: plaster)\\ continuing from one floor to the next [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper 2005] ]].**//|\\ 
-\\ 
- 
-==== Integration of beam heads ==== 
- 
-The refurbishment project with interior insulation shown in //**Figure 7**// is an example for the integration of beam heads: the airtight layer of the external wall is achieved through the interior plaster on the old brickwork. In this project, the defective beams were replaced with a construction with so-called “steel braces” with a welded base plate. The whole bearing head was packed in pressure-resistant insulation materials before being mounted in the wall (see [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[EnSan 2008] ]]). It was essential to connect the steel brace DIRECTLY with the plaster in an airtight manner. For this purpose, adhesive tape was used that could be plastered over, since leakages could be expected due to the movement of the components and the different thermal expansion coefficients of the steel brace and plaster. For this construction with interior insulation, it was necessary to prevent damp indoor air from reaching the colder support. There are also increased requirements for airtightness. //**Figure 8**// (upper part) shows the typical errors in basic planning that should be avoided during the connection of the interior insulation panels with the steel brace.\\ 
-\\ 
-|{{ :​picprivate:​refurbishment_airtightness_fig_8-a.jpg?​500 }}| 
-|{{ :​picprivate:​refurbishment_airtightness_fig_8-b.jpg?​500 }}| 
-|//**Figure 8: Airtight integration of the beam heads implemented as steel braces\\ when using calcium silicate interior insulation boards.\\ __Above:__ incorrect bonding to the calcium silicate board which does NOT\\ constitute the airtight layer.\\ __Below__: correct method connecting the steel brace with the airtight layer of\\ plaster ([[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper 2005] ]]).**//|\\ 
-\\ 
-|{{ :​picprivate:​ensan_r0010332.jpg?​600 }}|{{ :​picprivate:​ensan_r0010290_k.jpg?​286 }}| 
-|//**Figure 9: Beam heads implemented as steel braces before (left) and after (right) installation allready shown in Figure 8.\\ The airthigt layer and calcium silicate interior insulation boards are not installed yet.**//​||\\ 
-\\ 
-==== Interrupted airtight layer ==== 
- 
-Problems arise when the airtight layers of the different areas – usually the different storeys – cannot be connected with each other. In this case, as mentioned before, good values for the airtightness CANNOT be expected as a rule. A typical example is the connection of an attic room with the airtight layer of the wall of the room below. The schematic diagram in //**Figure 10**// shows both systematic approaches for a solution. One possibility is the airtight connection “through” or “in front of“ (around the outside) the wood beam ceiling (opening the ceiling, as in //**Figure 7**//). For this purpose the membrane can be passed directly between the beam heads, but must be carefully glued around each head. The other possibility is to wrap it all around the hollow space of the ceiling (in this cross-section,​ e.g. up to the opening for the stairs). This is the only way to ensure airtightness here.\\ 
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-|{{ :​picprivate:​refurbishment_airtightness_fig_10.jpg?​800 }}| 
-|//**Figure 10: Interruption of a continuous airtight layer by the wood beam ceiling. For the connection between the airtight layer of\\ the roof area and the wall area, either a connection “through” the ceiling can be chosen, or the whole roof area must be borde-\\ red airtightly from above and below, up to the opening for the stairs for example [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist/​Peper 2005] ]].**//|\\ 
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-There are also attempts for solving the problems by extending the membrane from the roof area (or the knee wall) in the floor build-up for a certain distance into the room (see //**Figure 11**// and //**Figure 12**//), instead of  directly connecting the two layers. The purpose is to sufficiently decrease the air permeability of the wall/floor area so that the necessary level of airtightness can be achieved. The longer distance is expected to increase the air permeability resistance. Even if screed is later applied which weighs down the membrane in the floor build-up, there will still be countless leakage paths in the area of the uppermost ceiling (see blue arrows in //**Figure 12**//). Because the brickwork generally has inadequate airtightness,​ the achievable value for the remaining leaks depends on the cumulative effect of the airtightness of the masonry. At the worst, the whole uppermost ceiling will have noticeable air flows and will constitute a kind of “cooling fin”. Air flows from numerous leaks from the ceiling into the other rooms. That is why it is strongly recommended that the connection of the airtight layers is uninterrupted so that air flows and the building damage resulting from these can be ruled out.\\ 
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-|{{ :​picprivate:​refurbishment_airtightness_fig_11.jpg?​500 }}| 
-|//**Figure 11: Airtight membrane laid in the area of the knee wall during the\\ modernisation of a Wilhelminian building in Hamburg. The membrane is\\ extended 50 cm into the room in the floor build-up [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper 2005] ]].\\ Will the area become airtight in this way?**//|\\ 
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-|{{ :​picprivate:​refurbishment_airtightness_fig_12.jpg?​500 }}| 
-|//**Figure 12: Detail of the knee wall area in Figure 11. The red arrows show the\\ two airtight layers which are not connected. The blue arrows indicate the air\\ flow paths that remain (leaks) [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Peper 2005] ]].**//|\\ 
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-==== Alternative:​ airtight layer on the "​outside"​ ====  
-In the case of exterior insulation, no-one wishes to make changes to the inside of their home, therefore any measures in the area of the wood beam ceiling are usually undesirable. In order to achieve an enclosing layer, one (although unusual) possibility is to position the airtight layer on the former exterior of the building. In the case of ordinary exterior insulation, the former exterior surface is situated on the warm inner side of the insulation afterwards. It is thus protected from thermal crack formation. The old exterior plaster must be stregnthened as an airtight layer since external plaster always has small cracks due to the greatly fluctuating climatic influences. The following possibilities for this are mentioned in [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]]: 
- 
-  * new plaster all over the old plaster. ​ As this new plaster will be protected by the compound insulation system later, new crack formation is unlikely (temperature amplitude at this position is only small as a large thermal mass is well insulated from the exterior surface and therefore a very long time constant results). 
-  * Overall application of the adhesive for attaching the compound insulation system on the old exterior plaster 
- 
-By placing the airtight layer at the exterior face of the brick walls, the envelope can enclose the wood beam ceiling area without problem. ​ In the “Jean-Paul-Platz“ project in Nuremberg this was successfully achieved (see [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Schulze Darup et al 2005] ]] and [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]]).  The windows must be connected with the new layer from the outside (masking with adhesive tape that can be plastered over).\\ 
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-|{{ :​picprivate:​refurbishment_airtightness_fig_13.jpg?​500 }}| 
-|//**Figure 13:​ Creating an airtight layer on the outside over the existing brickwork\\ with airtight integration of the windows [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]].**//|\\ 
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-==== Wall-to-basement connection ==== 
- 
-Near the rising brick wall of the basement, an area remains where the airtight layer is not continuously connected (//**Figure 14**//). What counts here is, how airtight the masonry is (checked area). Perfect results should not be expected. For the actual project in Nuremberg, the critical area being considered here turned out to be astonishingly airtight in practice. However, this result certainly cannot be transferred to modern masonry (with open joints) and vertically perforated masonry. For old solid brick masonry the cumulative airtightness effect through several metres of the wall may be sufficient.\\ 
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-|{{ :​picprivate:​refurbishment_airtightness_fig_14.jpg?​350 }}| 
-|//**Figure 14: A possible weak spot in an external airtight\\ layer at the transition of the external wall to the base-\\ ment ceiling ([[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]] supplemented).**//​|\\ 
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-==== Wall-to-roof and wall-to-uppermost ceiling connection ====  
- 
-Above in //**Figure 4**//, the course of the airtight layer can be seen on the old building surface. In the roof area the knee wall must be enclosed in the airtight layer.\\ 
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-|{{ :​picprivate:​refurbishment_airtightness_fig_15.jpg?​500 }}| 
-|//**Figure 15:​ Connection of the airtight layer of the top floor ceiling to the knee wall.\\ It should be noted that the new thermal insulation layer will be applied to this\\ membrane, therefore, as the vapour barrier, the membrane will be located on the\\ warm side ([[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]]).**//|\\ 
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-If the uppermost ceiling is executed as a concrete ceiling it will usually be sufficiently airtight. However, a wood beam ceiling is extremely non-airtight. It is quite difficult to strengthen the ceiling soffit on the inside of the airtight layer, even for the uppermost ceiling. ​ Usually there are significant leaks into the attic in old buildings. One way to deal with these is to lay a membrane on the ceiling of the top floor as shown in //**Figure 15**//. Improving the airtightness of the ceiling only makes sense when combined with the application of additional insulation on the ceiling. Only then will the new membrane be situated in the warm area and condensation can be ruled out.  ​ 
- 
-Achieving an uninterrupted airtight layer is made difficult by the comparatively complicated penetration details in the uppermost ceiling that are typical for old buildings. ​ Instructions for dealing with such penetrations are explained in [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]].  Experiences with the refurbishment of the uppermost ceiling of the building in Nuremberg are described here with some adapted texts and illustrations:​ 
- 
-An example of such a penetration is shown in //**Figure 16**//: reinforcing braces for the roof rise from the uppermost ceiling. If the airtight layer is situated on the floor boards, these braces will penetrate the airtight layer. Since the beams also have cracks in them, it will not be easy to ensure an airtight penetration here. //**Figure 16**// also shows a drawing for the solution to this problem and pictures of the details. The following instructions were devised for the demonstration project in Nuremberg:​\\ 
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-**I.** The surrounding area of the penetration should be cleaned. 
- 
-**II.** A strip of membrane is placed loosely around the penetration,​ the vertical width all around should be about 15 cm at least. 
- 
-**III.** 10 mm high battens ​ are placed around the penetration and nailed in, enough membrane should remain on both sides of the battens. 
- 
-**IV.** Wide cracks in the floor boards, beams and between the beams and floor boards or walls are plugged with fibres (or paper) so that the plaster used for (**V**) does not flow away. 
- 
-**V.** The areas prepared thus are poured with liquid gypsum, minimum height 5 mm. The materials used to plug the cracks (**IV**) should not stick out of the gypsum. The gypsum should easily infiltrate all the cracks in the wood beams etc.. It must overlap the membrane strips by at least 30 mm. 
- 
-**VI.** If the battens in (**III**) are in the way, they can be removed again after the gypsum has set; but they can also remain as they are. 
- 
-**VII.** The airtight membrane that is laid on the ceiling of the top floor is placed over the strips of membrane in (**II**) and stuck down. 
- 
-**VIII.** Thermal insulation must be applied on the upper side of the airtight layer.\\ 
-\\ 
-The advantage of using gypsum is that it does not shrink when it hardens, it expands slightly instead. In place of gypsum, other hardening sealing materials can also be used which are initially fluid and are either elastic or do not shrink.\\ 
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-|{{ :​picprivate:​refurbishment_airtightness_fig_16.jpg?​500 }}| 
-|//**Figure 16: Sealing in of braces penetrating the airtight layer of the topmost ceiling.\\ Above left: initial state with a brace penetrating the ceiling. Above centre: poured\\ gypsum is ready. Above right: The gypsum flows into all cracks. Below: drawing\\ showing this (principle [[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​airtightness#​Literature|[Feist 2003] ]]).**//|\\ 
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-This method represents a good and practicable solution for an airtight connection in a horizontal airtight layer. However, a very thin layer of plaster may break. Another possibility is to connect the membrane with the beam using an elastic sealing mass which can also be injected into large cracks and gaps of the beams.\\ 
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-===== See also ===== 
- 
-[[planning:​refurbishment_with_passive_house_components:​thermal_envelope:​Improving thermal bridges and airtightness in existing buildings]]\\ 
- 
-===== Literature ===== 
- 
-**[EN 13829]** EN 13829: Wärmetechnisches Verhalten von Gebäuden. Bestimmung der Luftdichtheit von Gebäuden. Differenzdruckverfahren\\ 
-(Thermotechnical behaviour of buildings. Differential pressure method) (ISO 9972:1996, modified), German version EN 13829:2000, DIN Deutsches Institut für Normung e.V., Beuth-Verlag,​ Berlin, February 2001.\\ 
-\\ 
-**[EnSan 2008]** EnSan (Energetische Verbesserung der Bausubstanz) Abschlussbericht vom Projekt „Hamburg, Kleine Freiheit 46-52\\ 
-(Energy-relevant improvement of building substance) “Final Report of the “Hamburg: Little Freedom 46-52” Funded project ID 0329750S. funded by PTJ. Steg Hamburg mbH, 2008.\\ 
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-**[Feist 1995]** Feist, Wolfgang: Die Luftdichtheit im Passivhaus;​\\ 
-(Airtightness in the Passive House) Passive House Report No. 6, Institute for Housing and Environment,​ Darmstadt, 1995.\\ 
-\\ 
-**[Feist 1997]** Feist, Wolfgang: Das Niedrigenergiehaus,​ Neuer Standard für energiebewusstes Bauen.\\ 
-(The low-energy house, a new standard for energy-conscious construction) C.F. Müller Verlag, 4th edition, Heidelberg, 1997.\\ 
-\\ 
-**[Feist 2003]** Feist, W.: Wärmebrücken und Verbesserung der Luftdichtheit im Altbau. In: Einsatz von Passivhaustechnologien bei der Altbau-Modernisierung\\ 
-(Thermal bridges and improvement of the airtightness in oild buildings. In “The use of Passive House technologies for the modernisation of old buildings”);​ Protocol Volume No. 24 of the Research Group for Cost-efficient Passive Houses Phase III; Passive House Institute; Darmstadt 2003.\\ 
-\\ 
-**[Feist/​Peper 2005]** Feist, W; Peper, S.: 3-D-Luftdichtheitsanschlüsse.\\ 
-(3-D Airtight connections) Passive House Institute, Darmstadt, 2005. Not published.\\ 
-\\ 
-**[FliB 2002]** Fachverband Luftdichtheit im Bauwesen e.V.\\ 
-(Specialists’ Association for airtightness in constructions) Supplementary Sheet for DIN EN 13829. Kassel, November 2002\\ 
-\\ 
-**[Kaufmann/​Peper/​Pfluger/​Feist 2009]** Kaufmann, B.; Peper, S.; Pfluger, R.; Feist, Wolfgang: Sanierung mit Passivhauskomponenten. ​ Planungsbegleitende Beratung und Qualitätssicherung Tevesstraße Frankfurt a.M.\\ 
-(Modernisation using Passive House components. ​ Consultation accompanying planning and quality assurance for Tevesstraße Frankfurt a.M.) 
-Passive House Institute Darmstadt, February 2009.\\ 
-\\ 
-**[Peper/​Feist/​Sariri 1999]** Peper, S.; Feist, W.; Sariri, V.: Luftdichte Projektierung von Passivhäusern,​\\ 
-(Airtight Planning of Passive Houses) CEPHEUS Project Information No. 7, Passive House Institute, Darmstadt 1999.\\ 
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-**[Peper 2000]** Peper, S.: Luftdichtheit bei Passivhäusern - Erfahrungen aus über 200 realisierten Objekten\\ 
-(Airtightness in Passive Houses – Experiences gained from over 200 realised buildings); Conference Proceedings of the 4th Passive House Conference, Passivhaus Dienstleistung GmbH, Kassel and Darmstadt, 2000.\\ 
-\\ 
-**[Peper 2005]** Peper; S.: Beratung zur Qualitätssicherung beim Projekt: „Hamburg, Kleine Freiheit 46-52, Energetische Verbesserung der Bausubstanz“.\\ 
-(Quality assurance for the project “Hamburg, Little Freedom 46-52: Energy-oriented improvement of the building substance”) within the framework of the PTJ sponsoring programme EnSan.\\ 
-\\ 
-**[Peper 2008]** Peper, S.: Luftdichtheit – unverzichtbar bei Passivhäusern.\\ 
-(Airtightness – indispensable in Passive Houses) in: Passive House Component Catalogue, Ecologically evaluated constructions. IBO (Österreichisches Institut für Baubiologie und -ökologie) Publiher: Springer Vienna New York. Second extended edition Wien 2008. ISBN 978-3-211-29763-6\\ 
-\\ 
-**[Peper/​Feist 2008]** Peper, S.; Feist, W.: Gebäudesanierung „Passivhaus im Bestand“ in Ludwigshafen / Mundenheim. ​ Messungen und Beurteilung der energetischen Sanierungserfolge.\\ 
-(“Existing Passive Houses”: building refurbishment in Ludwigshafen/​Mundenheim. Measurements and assessment of the success of energy-relevant modernisation) Passive House Institute, Darmstadt, December 2008.\\ 
-\\ 
-**[Peper/​Kah/​Feist 2005]** Peper, S.; Kah, O.; Feist, W.: Zur Dauerhaftigkeit von Luftdichtheitskonzepten bei Passivhäusern,​ Feldmessungen.\\ 
-(On the durability of concepts for airtightness in Passive Houses, field measurements) Research Report within the framework of the IEA SHC TASK 28 / ECBCS ANNEX 38.  Passive House Institute, Darmstadt, June, 2005.\\ 
-\\ 
-**[Schulze Darup et al 2005]** Schulze Darup, Burkhard (Herausgeber):​ Jean-Paul-Platz 4 in Nürnberg – energetische Gebäudesanierung mit Faktor 10. Abschlussbericht der wissenschaftlichen Begleitforschung.\\ 
-(Jean-Paul-Platz 4 in Nuremberg – energy-relevant modernisation of buildings with a factor of 10.  Final Report of the scientific monitoring),​ Nuremberg 2005.\\ 
-\\ 
-**[Zeller et al  1995]** Zeller,J.; Dorschky, S.; Borsch-Laaks,​ R.; Feist, W.: Luftdichtigkeit von Gebäuden – Luftdichtigkeits messungen mit der Blower Door in Niedrigenergiehäusern und anderen Gebäuden\\ 
-(Airtightness in buildings – measurement of airtightness by means of the blower door in low-energy houses and other buildings), Institut für Wohnen und Umwelt, Darmstadt, 1995. 
  
  
planning/refurbishment_with_passive_house_components/thermal_envelope/airtightness.txt · Last modified: 2019/02/07 11:40 by cblagojevic