Methods for testing the airtightness performance of buildings

Abstract

This invention provides an airtightness performance testing method that allows for easy testing of the airtightness performance of a building. [Solution] The solution comprises: an opening closing step (step S11) of closing an openable and closable opening 2 facing the outside of building 1; an internal pressure adjustment step (step S13) of operating a ventilation system 6 installed in building 1 to reduce or increase the pressure inside building 1 while the opening 2 is closed by the opening closing step; a pressure difference measurement step (step S16) of measuring a first pressure difference, which is the pressure difference between the inside and outside of building 1, while the inside of building 1 is reduced or increased by the internal pressure adjustment step; and an airtightness performance calculation step (step S17) of calculating the airtightness performance of building 1 based on the measurement result of the first pressure difference.

Description

[Technical Field]

[0001] This invention relates to a technology for testing the airtightness performance of buildings. [Background technology]

[0002] Conventionally, as described in Patent Document 1, there has been a demand for houses with excellent airtightness. The airtightness of houses has been tested (evaluated) using measuring instruments equipped with fans (blower). Furthermore, while there are almost no examples of measuring the airtightness of larger non-residential buildings in Japan, overseas, airtightness is sometimes tested using measuring instruments with a larger fan airflow than those used for houses.

[0003] However, measuring instruments for non-residential buildings have the drawback of being large in size, requiring considerable effort and time for installation and measurement, and placing a heavy burden on inspectors. On the other hand, when residential measuring instruments are applied to large non-residential buildings, the fan airflow of residential measuring instruments is insufficient. This insufficient airflow makes it difficult to create a pressure difference between the inside and outside of the building, thus making it difficult to test airtightness performance.

[0004] Therefore, a method for easily testing airtightness performance is desired, regardless of the size of the building. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2007-332533 [Overview of the project] [Problems that the invention aims to solve]

[0006] This invention was made in view of the above circumstances, and the problem it aims to solve is to provide an airtightness performance testing method that can easily test the airtightness performance of a building. [Means for solving the problem]

[0007] The problems that this invention aims to solve are as described above, and the means for solving these problems will now be explained.

[0008] In other words, claim 1 comprises: an opening closing step of closing an openable and closable opening facing the outside of a building; an internal pressure adjustment step of operating a ventilation system installed in the building to reduce or increase the pressure inside the building while the opening is closed by the opening closing step; a pressure difference measurement step of measuring a first pressure difference, which is the pressure difference between the inside and outside of the building, while the inside of the building is reduced or increased by the internal pressure adjustment step; and an airtightness performance calculation step of calculating the airtightness performance of the building based on the measurement result of the first pressure difference.

[0009] In claim 2, the internal pressure adjustment step is performed with the interior doors of the building open.

[0010] In claim 3, the internal pressure adjustment step is performed with the ceiling inspection hatch, which is provided in the ceiling separating the interior space and the ceiling space, open, when the second pressure difference, which is the pressure difference between the interior space and the ceiling space of the building, is greater than or equal to a predetermined value.

[0011] In claim 4, the pressure difference measurement step includes a measuring instrument installation step of setting up a plurality of measuring instruments for measuring the first pressure difference so that they are all facing in different directions, and the airtightness performance calculation step adopts the calculated value based on the measured value from each of the plurality of measuring instruments as the measurement result of the first pressure difference.

[0012] In claim 5, the airtightness performance calculation step calculates the total gap area of the building based on the measurement result of the first pressure difference and the ventilation design air volume of the building, and subtracts the ventilation port area of the ventilation equipment that is not operating in the internal pressure adjustment step from the total gap area to calculate the skin gap area of the building, and calculates the airtightness performance of the building based on the skin gap area.

[0013] In claim 6, the airtightness performance calculation step estimates the ventilation air volume of the building based on the measurement result of the first pressure difference and the pressure loss of the ventilation equipment, and calculates the total gap area using the estimated ventilation air volume instead of the ventilation design air volume.

Effect of the Invention

[0014] As an effect of the present invention, the following effects are achieved.

[0015] In claim 1, the airtightness performance of a building can be easily inspected.

[0016] In claim 2, the deviation of the pressure difference due to the location inside the building can be reduced.

[0017] In claim 3, the deviation of the pressure difference between the interior of the building and the ceiling space can be reduced.

[0018] In claim 4, the influence of the wind direction on the measured value of the pressure can be reduced.

[0019] In claim 5, the airtightness performance of a building can be inspected more easily.

[0020] In claim 6, the accuracy of the calculated airtightness performance can be improved.

Brief Description of the Drawings

[0021] [Figure 1]A schematic diagram showing the exterior appearance of a non-residential building that is subject to the airtightness performance inspection method according to one embodiment of the present invention. [Figure 2] A schematic cross-sectional diagram showing how pressure is measured inside a non-residential building and in the ceiling space using a pressure gauge. [Figure 3] A schematic cross-sectional diagram showing how pressure gauges measure the internal and external pressure of a non-residential building. [Figure 4] A flowchart illustrating the steps involved in the airtightness performance testing method. [Figure 5] A flowchart showing the detailed process for calculating airtightness performance. [Figure 6] A flowchart detailing another example of the calculation process for airtightness performance. [Figure 7] A diagram showing an example of the calculated airtightness performance, etc. [Modes for carrying out the invention]

[0022] The following describes an airtightness performance testing method according to one embodiment of the present invention.

[0023] An airtightness performance testing method according to one embodiment of the present invention is a method for testing the airtightness performance of a building 1. The airtightness performance testing method can be used for any building 1, but in this embodiment, it is used for non-residential buildings that are larger in scale than residential buildings. Non-residential buildings include various types of buildings such as offices, shops, gymnasiums, school buildings, medical and welfare facilities, apartment buildings and condominiums, and commercial facilities. The airtightness performance of building 1 is calculated based on the pressure difference between the inside and outside of building 1.

[0024] The configuration of Building 1 will be explained below using Figures 1 and 2.

[0025] As shown in Figure 1, the outer shell of building 1 is provided with an opening 2. The opening 2 is a portion that opens to the outside and is formed to be openable and closable. The opening 2 includes a window 2a and an exterior door 2b.

[0026] As shown in Figure 2, the interior of building 1 is provided with an interior space 3 and an attic 4. An interior door 3a is provided in the interior space 3. The interior door 3a is formed to open and close in the wall separating each room. The interior space 3 and the attic 4 are separated by a ceiling 5. A ceiling inspection hatch 5a is provided in the ceiling 5. The interior space 3 is provided with a ventilation system 6 for ventilating building 1. The ventilation system 6 includes an exhaust unit 6a and an air supply unit 6b. The ventilation system 6 may be a Type 1 ventilation system in which air is mechanically supplied by the air supply unit 6b and mechanically exhausted by the exhaust unit 6a, a Type 2 ventilation system in which air is mechanically supplied by the air supply unit 6b and naturally exhausted by the exhaust unit 6a, or a Type 3 ventilation system in which air is naturally supplied by the air supply unit 6b and mechanically exhausted by the exhaust unit 6a. In this embodiment, the ventilation system 6 is a Type 1 ventilation system.

[0027] Although only one internal door 3a is shown in the diagram, multiple internal doors 3a may be provided. Also, although only one exhaust section 6a and one intake section 6b are shown in the diagram, multiple exhaust sections 6a and intake sections 6b may be provided.

[0028] The following describes each step of the airtightness performance testing method using the flowchart shown in Figure 4.

[0029] In step S11, all openings 2 (windows 2a and exterior doors 2b, etc.) of building 1 facing the outside are closed (left closed).

[0030] In step S12, all interior doors 3a of building 1 are opened. The purpose of opening these interior doors 3a is to create a unified space within building 1 where there is no (or minimal) pressure unevenness depending on the location.

[0031] In step S13, the pressure difference between the interior space 3 and the ceiling space 4 of building 1 is checked. The pressure difference between the interior space 3 and the ceiling space 4 is measured using a pressure gauge 7 equipped with a first measuring section 7a and a second measuring section 7b. Specifically, as shown in Figure 2, the pressure gauge 7 is installed so that the first measuring section 7a is located in the ceiling space 4 and the second measuring section 7b is located in the interior space 3, and the pressure in the ceiling space 4 and the pressure in the interior space 3 are measured. This allows the pressure difference between the pressure in the interior space 3 and the pressure in the ceiling space 4 to be calculated.

[0032] Then, if the pressure difference between the indoor space 3 and the ceiling space 4 is greater than or equal to a predetermined value, the ceiling inspection hatch 5a is opened. This reduces the pressure difference between the indoor space 3 and the ceiling space 4, and consequently makes it possible to treat the interior of the building 1 as a more unified space. On the other hand, if the pressure difference between the indoor space 3 and the ceiling space 4 is less than the predetermined value, there is no need to open the ceiling inspection hatch 5a. Note that in step S13, the ceiling inspection hatch 5a may be opened regardless of the pressure difference between the indoor space 3 and the ceiling space 4.

[0033] In step S14, a pressure gauge 7 is installed to measure the pressure inside and outside the building 1 (step S16, described later). Specifically, as shown in Figure 3, the pressure gauge 7 is installed so that the first measuring section 7a of the pressure gauge 7 is located inside the building 1 (indoor space 3), and the second measuring section 7b is located outside the building 1.

[0034] In step S15, the ventilation system 6 is operated to depressurize or pressurize the interior of building 1. Specifically, when depressurizing the interior of building 1, at least some of the exhaust units 6a are operated and all of the supply units 6b are stopped, thereby expelling the air inside building 1 to the outside. On the other hand, when pressurizing the interior of building 1, at least some of the supply units 6b are operated and all of the exhaust units 6a are stopped, thereby drawing in air from outside building 1. Whether to depressurize or pressurize the interior of building 1 can be arbitrarily selected.

[0035] In step S16, the pressure difference ΔP between the inside and outside of building 1 is measured using the pressure gauge 7 installed in step S14. Specifically, when the inside of building 1 is depressurized in step S15, the pressure inside building 1 becomes lower than the pressure outside building 1, so the pressure difference ΔP is calculated by subtracting the internal pressure from the external pressure. On the other hand, when the inside of building 1 is pressurized in step S15, the pressure inside building 1 becomes higher than the external pressure, so the pressure difference ΔP is calculated by subtracting the external pressure from the internal pressure.

[0036] In step S17, the airtightness performance C of building 1 is determined based on the pressure difference ΔP measured in step S16. OS The calculation is performed as follows. The method for calculating the airtightness performance of Building 1 will be explained below using Figure 5.

[0037] In step S21, based on the pressure difference ΔP and ventilation airflow rate Q measured in step S16, the total gap area αA1 [cm²] of building 1 is calculated. 2 The total gap area αA1 is calculated. Here, "total gap area αA1" means the total area of ​​openings in building 1. Specifically, the total gap area αA1 is calculated by the following formula 1.

[0038] αA1=[Q / √{(2 / ρ)ΔP}]×(10000 / 3600)...Equation 1

[0039] In the above formula 1, "Q" is the ventilation airflow rate [m³ 3 This indicates [ / h]. Here, the ventilation airflow rate Q means the amount of air that the ventilation equipment 6 exhausts or supplies per unit time. The ventilation design airflow rate, which is the design value of the ventilation airflow rate, is used as the ventilation airflow rate Q. Also, "ρ" is the air density [kg / m³]. 3 This indicates [ ]. Also, "ΔP" represents the pressure difference [Pa] between the inside and outside of building 1, as described above, and was measured in step S16.

[0040] In step S22, the outer skin gap area αA is calculated by subtracting the ventilation port area of the ventilation facility 6 that stopped (not operating) in step S15 from the total gap area αA1. Here, the "outer skin gap area αA" means the area of the opening provided in the outer skin of the building 1. Specifically, the outer skin gap area αA is calculated by the following formula 2.

[0041] αA = αA1 - αA2 - αA3 ··· Formula 2

[0042] In the above formula 2, "αA1" indicates the total gap area [cm 2 calculated in step S21 as described above. Also, "αA2" indicates the opening area [cm 2 of the air supply port of the air supply part 6b that stopped (not operating) in step S15. Also, "αA3" indicates the opening area [cm 2 of the exhaust port of the exhaust part 6a that stopped (not operating) in step S15.

[0043] Here, the opening area αA2 of the air supply port of the stopped air supply part 6b is calculated by synthesizing the opening area α1A2 of the outdoor side ventilation port of the air supply part 6b and the opening area α2A2 of the indoor side air supply grille based on catalog values and the like. Specifically, the opening area αA2 of the air supply port of the stopped air supply part 6b is calculated by the following formula 3.

[0044] αA2 = 1 / √{(1 / α1A2) 2 + (1 / α2A2) 2} ··· Formula 3

[0045] Similarly, the opening area αA3 of the exhaust port of the stopped exhaust part 6a is calculated by synthesizing the opening area α1A3 of the outdoor side ventilation port of the exhaust part 6a and the opening area α2A3 of the indoor side exhaust grille based on catalog values and the like. Specifically, the opening area αA3 of the exhaust port of the stopped exhaust part 6a is calculated by the following formula 4.

[0046] αA3 = 1 / √{(1 / α1A3) 2 + (1 / α2A3) 2} ··· Formula 4

[0047] As shown in Figure 7, for example, the total gap area αA1 [cm²] 2 ] is 2534.0 [cm 2 ], the opening area αA2 of the air intake port of the stopped air intake unit 6b is 940.9 [cm² 2 ], the opening area αA3 of the exhaust port of the stopped exhaust section 6a is 51.6 [m² 2 If ] then, from equation 2 above, the outer shell gap area αA is 1541.5 [cm² 2 ]

[0048] Furthermore, the opening area αA3 of the exhaust port of the stopped exhaust section 6a is a certain value (for example, 10 cm²) confirmed by testing, if a backflow prevention valve is provided at the exhaust port of the exhaust section 6a. 2 It is said that...

[0049] In step S23, the airtightness performance C of building 1 is calculated by dividing the envelope gap area αA by the envelope area OS. OS [cm 2 / m 2 Calculate the airtightness performance C. OS " refers to the area of ​​air leakage per unit area OS of the building envelope 1, αA. Specifically, it refers to the airtightness performance C OS This is calculated by the following equation 5.

[0050] C OS =αA÷OS...Equation 5

[0051] In the above formula 5, "C OS " is, as mentioned above, the airtightness performance of building 1 [cm 2 / m 2 This indicates the outer shell gap area [cm²] calculated in step S22. "αA" is the outer shell gap area [cm²]. 2 ] indicates the outer surface area [m² 2 This shows the exterior surface area OS, which is the sum of the roof area and exterior wall area of ​​building 1.

[0052] As shown in Figure 7, for example, if the outer shell gap area αA is 1541.5 [cm²] 2 ], the outer surface area OS is 1508.1[m²2 If ] then, from the above formula 5, the airtightness performance C OS [cm 2 / m 2 ] is 1.02 [cm 2 / m 2 ]

[0053] Through the above process, the airtightness performance of building 1 can be inspected.

[0054] As described above, the airtightness performance testing method according to this embodiment allows for easy testing of the airtightness performance of a building 1 (especially a non-residential building larger in scale than a house). Specifically, since the ventilation equipment 6 installed in the building 1 is used instead of a blower (fan) that was conventionally used to test airtightness performance, extensive preparation is not required for the airtightness performance test, and the burden on the inspector can be reduced. Furthermore, since it is only necessary to operate the ventilation equipment installed in the building and measure the pressure difference between the inside and outside of the building with a pressure gauge, the preparation for the test can be made easy, and the time required for the test can be shortened.

[0055] Furthermore, since the airtightness performance is calculated by predicting the opening area of ​​all ventilation equipment 6 used for 24-hour ventilation and local ventilation, which are not related to airtightness performance (step S22 in Figure 5), there is no need to perform airtight sealing treatment such as sealing the ventilation openings of ventilation equipment 6 with tape. Therefore, the burden on inspectors regarding airtight sealing treatment can be reduced, especially in non-residential buildings where there are many ventilation equipment 6.

[0056] As described above, the method for testing the airtightness performance of building 1 according to this embodiment is The process involves closing the retractable opening 2 facing the outside of building 1 (step S11 in Figure 4), With the opening 2 closed by the opening closing process, the ventilation equipment 6 installed in the building 1 is operated to reduce or increase the pressure inside the building 1 in an internal pressure adjustment process (step S15 in Figure 4), With the interior of the building 1 depressurized or pressurized by the internal pressure adjustment process, a pressure difference measurement process (steps S14 and S16 in Figure 4) is performed to measure the first pressure difference, which is the pressure difference ΔP between the inside and outside of the building 1. A step (step S17 in Figure 4) is taken to calculate the airtightness performance of the building 1 based on the measurement results of the first pressure difference, It is equipped with the following features.

[0057] This configuration allows for easy inspection of the airtightness performance of building 1.

[0058] Furthermore, the internal pressure adjustment process is as follows: This is performed with the interior door 3a of the aforementioned building 1 open.

[0059] This configuration makes it possible to reduce the uneven distribution of pressure differences within the building 1.

[0060] Furthermore, the internal pressure adjustment process is as follows: If the second pressure difference, which is the pressure difference between the interior space 3 and the ceiling space 4 of the building 1, is greater than or equal to a predetermined value, the procedure is carried out with the ceiling inspection hatch 5a provided in the ceiling 5 separating the interior space 3 and the ceiling space 4 open (step S12 in Figure 4).

[0061] This configuration makes it possible to reduce the uneven pressure difference between the interior space 3 and the ceiling space 4 of building 1.

[0062] Furthermore, the process for calculating the airtightness performance is as follows: Based on the measurement results of the first pressure difference and the ventilation design airflow rate of the building, the total gap area αA1 of the building 1 is calculated (step S21 in Figure 5). The exterior gap area αA of the building 1 is calculated by subtracting the area of ​​the ventilation openings of the ventilation equipment 6 that is not operating during the internal pressure adjustment process from the total gap area αA1 (step S22 in Figure 5). Based on the aforementioned envelope gap area αA, the airtightness performance C of the building 1 OS This calculates (step S23 in Figure 5).

[0063] This configuration allows for easier inspection of the airtightness performance of building 1.

[0064] Although embodiments of the present invention have been described above, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the invention as described in the claims.

[0065] For example, in this embodiment, the interior of building 1 is depressurized or pressurized with all interior doors 3a of building 1 open (step S12 in Figure 4), but it is not necessary to open the interior doors 3a.

[0066] Furthermore, the internal pressure measurement of building 1 is easily affected by the direction of the wind blowing due to air intake or exhaust. The external pressure measurement of building 1 is also easily affected by the wind direction. For this reason, in step S14 of Figure 4, multiple pressure gauges 7 (at least one of the first measuring section 7a or the second measuring section 7b) may be installed facing different directions (for example, facing east, west, north, and south), and in step S16, the calculated value based on the measured values ​​from each of the multiple pressure gauges 7 may be adopted as the measurement result of the pressure difference ΔP in Equation 1 used in step S21 of Figure 5. The "calculated value based on measured values" can be, for example, the average value of the measured values ​​from each of the pressure gauges 7.

[0067] As described above, the pressure difference measurement process is This includes a measuring instrument installation step (step S14 in Figure 4) in which multiple pressure gauges 7 (measuring instruments) for measuring the first pressure difference are set up so that they are facing in different directions. The aforementioned airtightness performance calculation process is as follows: The calculated value based on the measurement values ​​from each of the multiple pressure gauges 7 is adopted as the measurement result of the first pressure difference.

[0068] This configuration reduces the influence of wind direction on pressure measurements.

[0069] Furthermore, in this embodiment, the ventilation design airflow rate is used to calculate the total gap area αA1 of building 1 (step S21 in Figure 5). However, there may be discrepancies between the ventilation design airflow rate and the actual ventilation airflow rate. For this reason, the ventilation airflow rate may be estimated based on the pressure loss of the ventilation equipment 6, and this estimated value may be used to calculate the total gap area αA1. This will be explained below using Figure 6.

[0070] In step S31, the static pressure acting on each ventilation unit 6 is calculated from the pressure loss of each ventilation unit 6 and the pressure difference ΔP measured in step S16. The pressure loss of each ventilation unit 6 can be obtained from catalog values.

[0071] In step S32, the ventilation airflow Q of the ventilation equipment 6 is estimated from the PQ characteristics (airflow-static pressure characteristics) of the ventilation equipment 6. The PQ characteristics represent the performance of the ventilation equipment 6 (ventilation fan) and show the relationship between the pressure (static pressure) at which the ventilation fan sends air and the amount of air (airflow) that the ventilation fan sends. By applying the static pressure of the ventilation equipment 6 calculated in step S31 to the PQ characteristics of the ventilation equipment 6, the ventilation airflow Q of the ventilation equipment 6 can be calculated.

[0072] In step S33, based on the pressure difference ΔP measured in step S16 and the ventilation airflow rate Q estimated in step S32, the total gap area αA1[m²] of building 1 is calculated. 3 The total gap area αA1 is calculated using the formula 1 (step S21) described above.

[0073] In steps S34 and S35, the envelope gap area αA is calculated using the same method as in steps S22 and S23, and the airtightness performance is calculated based on the envelope gap area αA.

[0074] In this way, by improving the accuracy of ventilation airflow, the accuracy of the calculated airtightness performance can be improved.

[0075] As described above, the airtightness performance calculation process is as follows: Based on the measurement results of the first pressure difference and the pressure loss of the ventilation equipment 6, the ventilation airflow rate of the building 1 is estimated (steps S31 and S32 in Figure 6). Instead of the ventilation design airflow rate, the estimated ventilation airflow rate is used to calculate the total gap area αA1 (step S33 in Figure 6).

[0076] This configuration improves the accuracy of the calculated airtightness performance.

[0077] Furthermore, in order to calculate the PQ characteristics (step S32 in Figure 6) and ventilation opening area (step S22 in Figure 5, step S34 in Figure 6) of each ventilation equipment 6, the model number of each ventilation equipment 6, its PQ characteristics, the type of outdoor ventilation opening and supply / exhaust grille, etc. may be registered in a database in advance, so that the PQ characteristics and ventilation opening area can be calculated using a calculation tool. This can reduce the time required for calculation. [Explanation of symbols]

[0078] 1. Building 2. Ventilation equipment 3 Indoor space 3a Internal door 4. Attic 5 Ceiling 5a Ceiling access hatch 6. Ventilation equipment 6a Exhaust section 6b Air supply section 7. Pressure gauge

Claims

1. An opening closing process that closes an openable and closable opening facing the outside of a building, With the opening closed by the aforementioned opening closing process, an internal pressure adjustment process is performed, in which the ventilation equipment installed in the building is operated to reduce or increase the pressure inside the building. A pressure difference measurement step is performed to measure a first pressure difference, which is the pressure difference between the inside and outside of the building, while the inside of the building is depressurized or pressurized by the internal pressure adjustment step. A process for calculating the airtightness performance of the building based on the measurement results of the first pressure difference, Equipped with, Methods for testing the airtightness performance of a building.

2. The aforementioned internal pressure adjustment process is: This is performed with the interior doors of the aforementioned building open. A method for testing the airtightness performance of a building according to claim 1.

3. The aforementioned internal pressure adjustment process is: If the second pressure difference, which is the pressure difference between the interior space of the building and the space above the ceiling, is greater than or equal to a predetermined value, the inspection is carried out with the ceiling inspection hatch provided in the ceiling separating the interior space and the space above the ceiling open. A method for testing the airtightness performance of a building according to claim 1.

4. The pressure difference measurement step is, The process includes setting up multiple measuring instruments for measuring the first pressure difference, each facing a different direction. The aforementioned airtightness performance calculation process is as follows: The calculated value based on the measurement values ​​from each of the multiple measuring instruments is adopted as the measurement result of the first pressure difference. A method for testing the airtightness performance of a building according to claim 1.

5. The aforementioned airtightness performance calculation process is as follows: Based on the measurement results of the first pressure difference and the ventilation design airflow rate of the building, the total gap area of ​​the building is calculated. The building envelope gap area is calculated by subtracting the area of ​​the ventilation openings of the ventilation equipment that is not operating during the internal pressure adjustment process from the total gap area. Based on the aforementioned gap area of ​​the building envelope, the airtightness performance of the building is calculated. A method for testing the airtightness performance of a building according to any one of claims 1 to 4.

6. The aforementioned airtightness performance calculation process is as follows: Based on the measurement results of the first pressure difference and the pressure loss of the ventilation equipment, the ventilation airflow rate of the building is estimated. Instead of the aforementioned ventilation design airflow, the estimated ventilation airflow is used to calculate the total gap area. A method for testing the airtightness performance of a building according to claim 5.

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