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efficiency_now:building_envelope:interiorinsulation

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efficiency_now:building_envelope:interiorinsulation [2022/12/01 08:14] – yaling.hsiao@passiv.deefficiency_now:building_envelope:interiorinsulation [2022/12/09 02:52] (current) – [See also] yaling.hsiao@passiv.de
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-====== Thermal protection using interior insulation ====== 
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- ** * [[efficiency_now:building_envelope:interiorinsulation:interior insulation calculator| Interior insulation calculator]]** 
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- ** * [[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation| Blown-in interior insulation using capillary-active insulation material]]** 
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 ====== Thermal protection using interior insulation ====== ====== Thermal protection using interior insulation ======
  
 **Because interior insulation is better than you think!** **Because interior insulation is better than you think!**
  
-|**Quick links**|[[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation|Blown-in interior insulation]]|[[https://passipedia.de/baulich/innendaemmung_mit_mineralschaumplatten|Capillary-active mineral foam panels]]|[[efficiency_now:building_envelope:interiorinsulation:vapourretarder| Traditional interior insulation with a vapour retarder]]|+|**Quick links**|[[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation| Blown-in interior insulation using capillary-active insulation material]]|[[https://passipedia.de/baulich/innendaemmung_mit_mineralschaumplatten|Capillary-active mineral foam panels]]|[[efficiency_now:building_envelope:interiorinsulation:vapourretarder| Traditional interior insulation with a vapour retarder]]|[[efficiency_now:building_envelope:interiorinsulation:interior insulation calculator| Interior insulation calculator]]|
  
 ===== Preface: exterior insulation or interior insulation? ===== ===== Preface: exterior insulation or interior insulation? =====
  
-Improved thermal protection is a crucial prerequisite for a comfortable living environment, hygienic indoor space conditions and energy efficient operation of modern heating systems. In the Central European climate heat losses through exterior walls are actually the predominant losses in existing buildings (usually over 50%) - and they can be reduced by several times (by a factor of 3 if done properly) also by means of interior insulation. In Passipedia we have described why we prefer [[https://passipedia.de/planung/sanierung_mit_passivhaus_komponenten/waermeschutz|exterior insulation]] whenever possible. However, we also realise that this is not always possible. In such cases, precedence should be given to insulation on the inside over inadequate insulation or no insulation at all - provided that the interior insulation measure is properly planned and implemented. The indoor climate will then be better with the interior insulation compared to no insulation - and this is true for each of the systems we have described here. The moisture balance of the exterior wall plays a significant role in this, this has been extensively investigated and resolved, see our publications on the topic of [[https://passipedia.de/planung/sanierung_mit_passivhaus_komponenten/loesungen_fuer_den_feuchteschutz#loesungen_fuer_den_feuchteschutz|moisture protection]]. Here, we will focus on how such solutions can be implemented in practice. The instructions provided here are naturally not a substitute for individual advice.+Improved thermal protection is a crucial prerequisite for a comfortable living environment, hygienic indoor space conditions and energy efficient operation of modern heating systems. In the Central European climate heat losses through exterior walls are actually the predominant losses in existing buildings (usually over 50%) - and they can be reduced by several times (by a factor of 3 if done properly) also by means of interior insulation. In Passipedia we have described why we prefer [[planning:refurbishment_with_passive_house_components:thermal_envelope|exterior insulation]]  whenever possible. However, we also realise that this is not always possible. In such cases, precedence should be given to insulation on the inside over inadequate insulation or no insulation at all - provided that the interior insulation measure is properly planned and implemented. The indoor climate will then be better with the interior insulation compared to no insulation - and this is true for each of the systems we have described here. The moisture balance of the exterior wall plays a significant role in this, this has been extensively investigated and resolved, see our publications on the topic of [[https://passipedia.de/planung/sanierung_mit_passivhaus_komponenten/loesungen_fuer_den_feuchteschutz#loesungen_fuer_den_feuchteschutz|moisture protection]]. Here, we will focus on how such solutions can be implemented in practice. The instructions provided here are naturally not a substitute for individual advice.
  
 ===== Interior insulation – done properly  ===== ===== Interior insulation – done properly  =====
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   * All the methods with decreasing interior insulation that tapers off as described here for the example of an interior wall should also be used in other places where the interior insulation would otherwise end "abruptly" ((E.g. the strip of the wall mentioned in the example above where there is a water-carrying pipe )) ((Or the heat conducting plate)).   * All the methods with decreasing interior insulation that tapers off as described here for the example of an interior wall should also be used in other places where the interior insulation would otherwise end "abruptly" ((E.g. the strip of the wall mentioned in the example above where there is a water-carrying pipe )) ((Or the heat conducting plate)).
  
-The exact details ((Usually an "insulation wedge" )) depend on the situation found at the structure and on the system selected. For this reason, the details are described in the respective individual instructions which are tailored to the respective method, e.g. here:+The exact details ((Usually an "insulation wedge" )) depend on the situation found at the structure and on the system selected. For this reason, the details are described in the respective individual instructions which are tailored to the respective method, e.g. here:\\
 **[[[[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation|Loose-fill interior insulation using capillary-active insulation material]]**\\ **[[[[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation|Loose-fill interior insulation using capillary-active insulation material]]**\\
-**[[https://passipedia.org/efficiency_now/building_envelope/interiorinsulation/vapourretarder|Interior insulation with vapour retarder]]**+**[[efficiency_now:building_envelope:interiorinsulation:vapourretarder|Interior insulation with vapour retarder]]**
  
 By the way, with regard to flanking insulation at the edges, it is NOT absolutely necessary to rigidly adhere to the "system" all the time: e.g. for a solution with a vapour retarder, it is certainly possible for the flanking insulation for an interior wall (e.g. insulation wedge) to consist of a capillary active material (or vice versa). It is easy to understand why this is the case, anyone interested in the subject can read about this **here** ((The flanking insulation only serves to slightly raise the surface temperature at such places where the abrupt end of the interior insulation would otherwise result in low interior surface temperatures. This is done by continuing the flanking insulation a little bit further with a tapering effect; even if this kind of flanking insulation might only be "thin" (an insulation thickness of 2 cm is usually sufficient, more is naturally possible), it fulfils this purpose exactly. The only thing that must always be avoided here is that indoor air can flow behind such flanking insulation - so it is essential, for example, to apply adhesive all over the surface, which is not really a problem with such small areas. We have examined the issues relating to water vapour diffusion using multi-dimensional transient simulations, the results can be found here: [[https://passipedia.de/planung/sanierung_mit_passivhaus_komponenten/loesungen_fuer_den_feuchteschutz/4.9_einbindende_innenwaende|Why edge areas are unproblematic in terms of diffusion as soon as the internal surface temperatures are right (German only)]]; by the way, only a thickness of 1 cm and only a 20 cm extension of the flanking insulation was applied for the calculation in order to remain completely on the safe side. We recommend sticking to the maximum possible thickness here (at least 2 cm, this is usually possible: otherwise advice should be sought) and also choosing 30 to 50 cm for tapering off; reveals must always be insulated fully, in the case of exterior building assemblies, it MUST be an insulation wedge. To summarise: the lateral diffusion flow through the existing building components mitigates the situation here because the "interior components" are all dry - and the standard insulated elements of the exterior wall with newly applied interior insulation are also "dry enough"  if this is executed as described. The latter are only "cold". This must not penetrate to the interior surface at the edge.)). In conclusion, this takes a lot of stress out of implementation in practice, because very inexpensive insulation wedges made of different materials are available from various manufacturers. One of them will certainly be appropriate ((The reason why such extreme 'warnings' regarding this are issued by some is because: A) often it is not recognised or even denied that from the building physics perspective, it depends mainly on **airtightness towards the room side**; that’s already 75% of the total amount. This is very easily resolved:  e.g. by applying adhesive all over the surface. B) even a diffusion bridge, which always has a supportive effect in this case, is often not really understood by experts.   Many people have a "thermal bridge" in their mind but this is completely different with regard to heat flow, which is exactly why flanking **insulation** is required. C) Added to this, unfortunately, is the fact that it suits many experts if all this is seen as being extremely difficult so that they may provide expensive individual advice to everyone. Sadly, this kind of thing is a widespread phenomenon in our society, also in many other areas. D) This applies to an even greater degree for manufacturers of the systems. For a few flanking insulation solutions, some of them provide extremely expensive special products and of course they want people to buy these; frequently, there are much cheaper solutions available from other manufacturers. If our instructions are adhered to (especially: "airtight towards the indoor space"), then the problems will be solved. By the way, in cases which seem too complicated or which you are not completely sure about, designers and consultants who are qualified in the field of Passive House construction can also take a look at the details in such issues; and it doesn't have to cost a lot. Their main focus is ensuring that problems do not arise, they don't want to sell anything, especially not "special products". And, the fact that they can do this is proved by the hundreds of thousands of successfully implemented Passive House buildings and thousands of successful deep retrofits to the EnerPHit standard.)). By the way, with regard to flanking insulation at the edges, it is NOT absolutely necessary to rigidly adhere to the "system" all the time: e.g. for a solution with a vapour retarder, it is certainly possible for the flanking insulation for an interior wall (e.g. insulation wedge) to consist of a capillary active material (or vice versa). It is easy to understand why this is the case, anyone interested in the subject can read about this **here** ((The flanking insulation only serves to slightly raise the surface temperature at such places where the abrupt end of the interior insulation would otherwise result in low interior surface temperatures. This is done by continuing the flanking insulation a little bit further with a tapering effect; even if this kind of flanking insulation might only be "thin" (an insulation thickness of 2 cm is usually sufficient, more is naturally possible), it fulfils this purpose exactly. The only thing that must always be avoided here is that indoor air can flow behind such flanking insulation - so it is essential, for example, to apply adhesive all over the surface, which is not really a problem with such small areas. We have examined the issues relating to water vapour diffusion using multi-dimensional transient simulations, the results can be found here: [[https://passipedia.de/planung/sanierung_mit_passivhaus_komponenten/loesungen_fuer_den_feuchteschutz/4.9_einbindende_innenwaende|Why edge areas are unproblematic in terms of diffusion as soon as the internal surface temperatures are right (German only)]]; by the way, only a thickness of 1 cm and only a 20 cm extension of the flanking insulation was applied for the calculation in order to remain completely on the safe side. We recommend sticking to the maximum possible thickness here (at least 2 cm, this is usually possible: otherwise advice should be sought) and also choosing 30 to 50 cm for tapering off; reveals must always be insulated fully, in the case of exterior building assemblies, it MUST be an insulation wedge. To summarise: the lateral diffusion flow through the existing building components mitigates the situation here because the "interior components" are all dry - and the standard insulated elements of the exterior wall with newly applied interior insulation are also "dry enough"  if this is executed as described. The latter are only "cold". This must not penetrate to the interior surface at the edge.)). In conclusion, this takes a lot of stress out of implementation in practice, because very inexpensive insulation wedges made of different materials are available from various manufacturers. One of them will certainly be appropriate ((The reason why such extreme 'warnings' regarding this are issued by some is because: A) often it is not recognised or even denied that from the building physics perspective, it depends mainly on **airtightness towards the room side**; that’s already 75% of the total amount. This is very easily resolved:  e.g. by applying adhesive all over the surface. B) even a diffusion bridge, which always has a supportive effect in this case, is often not really understood by experts.   Many people have a "thermal bridge" in their mind but this is completely different with regard to heat flow, which is exactly why flanking **insulation** is required. C) Added to this, unfortunately, is the fact that it suits many experts if all this is seen as being extremely difficult so that they may provide expensive individual advice to everyone. Sadly, this kind of thing is a widespread phenomenon in our society, also in many other areas. D) This applies to an even greater degree for manufacturers of the systems. For a few flanking insulation solutions, some of them provide extremely expensive special products and of course they want people to buy these; frequently, there are much cheaper solutions available from other manufacturers. If our instructions are adhered to (especially: "airtight towards the indoor space"), then the problems will be solved. By the way, in cases which seem too complicated or which you are not completely sure about, designers and consultants who are qualified in the field of Passive House construction can also take a look at the details in such issues; and it doesn't have to cost a lot. Their main focus is ensuring that problems do not arise, they don't want to sell anything, especially not "special products". And, the fact that they can do this is proved by the hundreds of thousands of successfully implemented Passive House buildings and thousands of successful deep retrofits to the EnerPHit standard.)).
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 The high amount of water vapour partial pressure which exists in the indoor air in winter can also cause moisture transport towards the (now cold) old wall structure behind interior insulation due also to water vapour diffusion ((Very little water vapour is actually transported here, with classic exterior walls this is about 5 g per m² per day at the most. For removing moisture out of the indoor space this does not play any role - just one person alone releases approximately 2.4 kg of water vapour into the indoor air each day. But: over the course of the year, a few grams may accumulate in an incorrectly built wall structure. This can happen especially if the water vapour gets into the wall structure easily but cannot leave it again so easily.)). There are two different concepts possible for avoiding moisture-related damage: The high amount of water vapour partial pressure which exists in the indoor air in winter can also cause moisture transport towards the (now cold) old wall structure behind interior insulation due also to water vapour diffusion ((Very little water vapour is actually transported here, with classic exterior walls this is about 5 g per m² per day at the most. For removing moisture out of the indoor space this does not play any role - just one person alone releases approximately 2.4 kg of water vapour into the indoor air each day. But: over the course of the year, a few grams may accumulate in an incorrectly built wall structure. This can happen especially if the water vapour gets into the wall structure easily but cannot leave it again so easily.)). There are two different concepts possible for avoiding moisture-related damage:
  
-**Solution I** is the "classic concept": water vapour diffusion from the inside towards the outside is stopped (vapour barrier) or at least impeded **(vapour retarder)** strongly enough to protect the cold construction from moisture exposure. This solution has proved successful for decades with thousands of implemented measures, sometimes even in very demanding conditions (e.g. in indoor swimming pools). Simulations have shown that with the normal utilisation of living spaces, a minimum value of more than 15 m should be complied with for the effective water vapour diffusion-equivalent thickness of sd,eff [AkkP 32]. With appropriate sheeting, this diffusion-equivalent thickness is stated in the product data sheet. How this is done in practice is described here: Interior insulation: [[https://passipedia.org/efficiency_now/building_envelope/interiorinsulation/vapourretarder|classic method using a vapour retarder.]]\\+**Solution I** is the "classic concept": water vapour diffusion from the inside towards the outside is stopped (vapour barrier) or at least impeded **(vapour retarder)** strongly enough to protect the cold construction from moisture exposure. This solution has proved successful for decades with thousands of implemented measures, sometimes even in very demanding conditions (e.g. in indoor swimming pools). Simulations have shown that with the normal utilisation of living spaces, a minimum value of more than 15 m should be complied with for the effective water vapour diffusion-equivalent thickness of sd,eff [AkkP 32]. With appropriate sheeting, this diffusion-equivalent thickness is stated in the product data sheet. How this is done in practice is described here: Interior insulation: [[efficiency_now:building_envelope:interiorinsulation:vapourretarder|classic method using a vapour retarder.]] \\
  
 For **Solution II**, namely the **"use of capillary-active insulation materials"**, field applications have also been carried out successfully for some years with good results [AkkP 32]. Water vapour can diffuse through a diffusion-permeable (but airtight) build-up with a capillary-active insulation material. However, a capillary-active insulation material only absorbs some of the moisture and stores this in the pores. This sorbate is transported further into the material due to liquid water transport. According to the incline in the relative humidity, sorbate moisture transport in winter takes place in the inwards direction. However, it is precisely experts who, for  whatever reasons, warn against using "capillary-active insulation materials" as a universal remedy for the moisture load in exterior walls of existing buildings without remedying the cause of this moisture load, because return transport of the moisture (through surface diffusion) is limited. Details about this type of implementation can be found here: [[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation|Loose-fill interior insulation with capillary-active insulation material.]] For **Solution II**, namely the **"use of capillary-active insulation materials"**, field applications have also been carried out successfully for some years with good results [AkkP 32]. Water vapour can diffuse through a diffusion-permeable (but airtight) build-up with a capillary-active insulation material. However, a capillary-active insulation material only absorbs some of the moisture and stores this in the pores. This sorbate is transported further into the material due to liquid water transport. According to the incline in the relative humidity, sorbate moisture transport in winter takes place in the inwards direction. However, it is precisely experts who, for  whatever reasons, warn against using "capillary-active insulation materials" as a universal remedy for the moisture load in exterior walls of existing buildings without remedying the cause of this moisture load, because return transport of the moisture (through surface diffusion) is limited. Details about this type of implementation can be found here: [[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation|Loose-fill interior insulation with capillary-active insulation material.]]
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 ===== See also ===== ===== See also =====
  
-[[efficiency_now:building_envelope:interiorinsulation:vapourretarder|Specifically: Interior insulation with a vapour retarder]] \\  +[[efficiency_now:building_envelope:interiorinsulation:vapourretarder|Interior insulation with a vapour retarder]] \\ 
- +
-[[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation|Specifically: Loose-fill insulation]] \\ +
- +
-[[https://passipedia.de/baulich/waermeschutz_durch_innendaemmung/aussenbauteilen_mit_innendaemmung|Moisture transport process in exterior building assemblies with interior insulation ( German only)]] :?: ** there is unfinished English version https://passipedia.org/playground/moisture_transport_process_in_exterior_building_components_with_interior_insulation **\\ +
- +
-**[[efficiency_now:building_envelope|"Back to overview of "Structural measures for saving energy]]** \\+
  
-[[efficiency_now:building_envelope:exteriorinsulation|Alternatively: Exterior insulation measures for exterior walls]] :?: here is an complete version (https://passipedia.org/playground/thermal_protection_using_exterior_insulation) \\+[[efficiency_now:building_envelope:interiorinsulation:blow_in_interiorinsulation|Loose-fill insulation]] \\
  
-[[https://passipedia.de/baulich/vorgehaengte_hinterlueftete_fassade|Alternatively: Thermal protection using a thermal bypass rainscreen façade (German only)]] \\+Back to overview of [[efficiency_now:building_envelope|Structural measures for saving energy]] \\
  
-[[efficiency_now:building_envelope:exteriorinsulation:blown-in_insulation_material|Alternatively: Plaster base formwork for subsequent loose-fill insulation]] \\+[[efficiency_now:building_envelope:exteriorinsulation|Exterior insulation measures for exterior walls]]
  
-[[https://passipedia.de/baulich/waermeschutz_durch_kerndaemmung|Insulating the air space in a cavity wall (German only)]] \\+[[efficiency_now:building_envelope:exteriorinsulation:blown-in_insulation_material|Plaster base formwork for subsequent loose-fill insulation]] \\
  
-[[planning:thermal_protection|General information on thermal protection of buildings]] \\+General information on [[planning:thermal_protection|thermal protection of buildings]] \\
  
 ===== Reference literature ===== ===== Reference literature =====
efficiency_now/building_envelope/interiorinsulation.1669878857.txt.gz · Last modified: 2022/12/01 08:14 by yaling.hsiao@passiv.de