BUILDING ENVELOPE

FIELD OF THE INVENTION

The invention relates to the field of communication systems, assemblies, methods and computer program products for measuring a condition of a building envelope.

BACKGROUND OF THE INVENTION

A building has an outer layer, which deteriorates over time. The

deterioration of the outer layer is seen in the decrease of the insulation capabilities of the outer layer. The deterioration of the outer layer is alternatively seen in a decrease of the structural integrity of the outer layer. Further, the outer layer is exposed to the weather. This exposure enhances the deterioration effect of the outer layer. The outer surface often includes a protective layer of paint or other type of coating. This protective layer also deteriorates over time.

The outer layer of the building is to be maintained to preserve or at least minimize the decrease of the insulation capabilities. Therefore, the protective layer is to be reapplied once in a while, as an example. Furthermore, parts of the outer layer may need to be replaced. For example, a wood rotten window frame is replaced with a new window frame.

A disadvantage of the current maintenance of the outer layer of a building is that maintenance is currently planned years in advance primarily based on theoretical information.

SUMMARY OF THE INVENTION

An object of the current invention is to optimize the use of building materials in the outer layer. Another object of the current invention is to measure the condition of the building envelope more accurately.

According to a first aspect of the current invention, a system for measuring a degradation condition of a building envelope comprising different building units, comprising: one or more sensors arranged for measuring a degradation parameter of each of the building units; a processing unit configured for determining the degradation condition based on the measurements; and a presentation unit configured for presenting the degradation condition.

It is an insight of the inventors that as maintenance is planned years in advance, the maintenance of the outer layer is either too early or too late, but hardly ever on time. Furthermore, the maintenance is primarily or even solely based on theoretical assumptions, without actually measuring or only measuring at intervals of one year or longer. The outer layer may comprise a protective layer. If maintenance is done too early, reapplying a protective layer is a waste of material of the old protective layer, which was still in a condition to provide protection for the other layers in the building envelope. This causes a waste of protective layer material. As a further example, if maintenance is done too early, parts of the building envelope and/or fagade may be replaced during maintenance, while the condition of these parts may still be acceptable. Thus, this may cause a waste of the replaced parts.

If maintenance is done too late, the protective layer may already not be in a condition to protect the other layers of the building envelope and/or the interior of the building. As a further example, if maintenance is done too late, parts of the building envelope may already have deteriorated and/or degraded such that the building envelope is not in a condition to shield or protect the interior of the building. Thus, maintenance done too late may cause additional replacement of parts of the building causing a waste of material.

The current invention provides the advantage of being able to optimize the moment in time, such as just in time, maintenance on a building envelope and/or fagade needs to be done having the technical effect to optimize the use of building material. The current invention has the further advantage of having an increased reproducibility compared to human inspection. The current invention has the further advantage of measuring always with the same accuracy independent of the weather.

A multitude of different building units form a building envelope and/or fagade. It is a further insight of the inventor that different building units, building elements and/or different materials degrade differently. Where one building unit degrades faster under the influence of certain ecological environmental influences, such as temperature swings, another building unit degrades faster under the influence of sunshine, such as UV, ozone, atmospheric pollution, heat, cold and user traces. As the degradation is typically influenced not only simply by the passing of time, degradation and deterioration prediction is difficult or even impossible. Thus, sensors are needed for doing measurements to come to predictive maintenance. In an embodiment of the invention, at least two sensors measure the degradation and/or deterioration parameter of the same building unit, building elements and/or different materials. As the sensors are typically low in cost, the reliability is typically also low. It makes it possible to use this embodiment (way of monitoring) by using multiple sensors, which provides the advantage of, among other things, increased reliability / accuracy. This embodiment provides the advantage of increased reliability by providing a back-up sensor or additional sensor, such as second, third or fourth sensor, per building unit, building elements and/or different materials.

In an embodiment of the invention, the at least two sensors use two distinct technologies for measuring the degradation and/or deterioration parameter. It is an insight of the inventor that a sensor is typically suitable for a specific range and/or product / material. Or in other words is accurate at a specific range, but is also inaccurate over another part of the range. Applying two different technologies advantageously allows for measuring the degradation parameter over the full range with a high accuracy.

In an embodiment of the invention, the multiple building units, building element and/or materials form a fagade of the building. The degradation typically varies per fagade of a building envelope. A fagade facing south may degrade more due to exposure to ecological environment (like as: sunlight, UV, Ozon radiation etc.), while a fagade facing north may degrade for example more due to moist. The degradation and/or deterioration condition may therefore be advantageously

determined per fagade, building block, building element and/or different material.

In an embodiment of the invention, the one or more sensors measures non- destructive. A lot of measurements involve destructive measurements. For example, detecting the early stages of wood rot is done by checking the moist in wood, which is typically done by piercing the wood with the tip of a moist sensor. This piercing then also pierces the protective coating or paint layer, leaving an opening for moist to enter the wood. This embodiment advantageously allows for non-destructive measurements.

In an embodiment of the invention, the degradation and/or deterioration condition is derived from the measurements. The degradation and/or deterioration condition may be a compilation of measured parameters, such that the measured parameters are not presented. For example, when measuring moist in wood, the actual question is if the wood is rotting. And if so, if the wood needs replacement. Thus, presenting the amount of moist in the wood, measured by determining the dielectric constant with a high frequency, does not provide the information to the user of the system. For example, the system may present a condition stating the change of having wood rot. Hence, the system advantageously provides a condition derived from the measured parameters.

In an embodiment of the invention, the system measures continuously and/or real-time. Current maintenance plans are only monitored once a year. In the context of the current application, real-time and/or continuous measurement is doing a measurement multiple times a month, preferably, multiple times a week, more preferably multiple times a day, most preferably once or multiple times an hour. The ecological environment, such as the weather, climate and/or seismic influence, may have a great or even dominant influence on the deterioration and/or degradation rate of the building envelope, fagade, building elements and/or different types of materials. As the ecological environment may change greatly over time, the influence of this change is taken into account with the inventive system. A change in ecological environment may be an extremely warm and sunny summer drying out and thereby influencing the deterioration and/or degradation rate of the building envelope, building units, building elements and/or different type of materials. Another change in the ecological environment may be a very cold winter cooling and thereby possibly crumbling and thus influencing the deterioration and/or degradation rate of the building envelope, building blocks, building elements and/or different type of materials. As another change in the ecological environment may be a period wherein rainy times and dry sunny times are alternating, which may cause the building envelope, building blocks, building elements and/or different type of materials to develop cracks and thus influence the deterioration en degradation rate of the building envelope/ fagade. As yet another example is the change in the ecological environment, a relatively calm and cloudy period with a stable temperature which may cause the deterioration and/or degradation rate to be minimal, which may cause the building envelope and/or fagade to be used for a longer period of time without any maintenance, financial and/or economical and/or sustainability waste. Measuring continuously and/or real-time provides the advantage that the change in condition of the building envelope and/or fagade may be accurately followed, predictive maintenance. Furthermore, it provides the advantage of being able to improve the prediction of the condition, such as the deterioration and/or degradation rate, of the building envelope, building blocks, building elements and/or different type of materials. In an embodiment of the invention, the building envelope and/or fagade comprises building units, building blocks and/or building elements having a building unit parameter and wherein the plurality of sensors is arranged to the building units for measuring a building unit parameter. As a building envelope is build up at least partly from building blocks, building elements and/or building units, the building may be better to maintain. Furthermore, as the building envelope and/or fagade is built up at least partly from building blocks and/or building elements, the system is able to

advantageously specify the condition more accurately per building block and/or building element.

In an embodiment of the invention, the building envelope comprises pre- fabricated building units having at least part of the plurality of sensors arranged to the pre-fabricated building units for measuring a parameter, such as a deterioration and/or degradation parameter, of the pre-fabricated building units. A pre-fabricated building block, such as an architectural building element, an architectural fagade element or architectural fagade element building shell, is a building block, which is formed in a factory and thereafter transported to the site where the building is to be build or maintained. A pre-fabricated building block may be arranged to another pre-fabricated building block on site. As the sensors are already arranged during production of the pre-fabricated building blocks are more easily placed during build or maintenance of the building envelope. Furthermore, the pre-arranged sensors may also be calibrated during production making them more accurate. Furthermore, the pre-arranged sensors may also be arranged more accurately during production making the measurements more reliable.

In an embodiment of the invention, wherein the plurality of sensors measures at least two different parameters. Preferably the two different parameters are independent of each other. This provides the advantage of improved determining the condition of the building envelope and/or fagade.

In an embodiment of the invention, the processing unit is further arranged for determining the condition based on a type of material used in the building envelope. This embodiment advantageously takes into account the type of material for more accurately determining and predicting the condition of the building envelope. This embodiment may be even more advantageous if a pre-fabricated building block is used in combination with a pre-arranged sensor to the pre-fabricated building block.

In an embodiment of the invention, the processing unit is further configured for determining the condition based on dimensions, geographical location and/or an orientation of the building envelope. The orientation and/or geographic location, specifically in combination with the ecological environment, may have a great influence on the condition, such as the deterioration and/or degradation rate of the building envelope. As a part of the building envelope on the south side of the building in the northern hemisphere may be exposed much more to different ecological environment, such as sunlight, compared to a part of the building envelope on the north side.

Furthermore, a part of the building envelope in the shade of some other object, such as another part of the building, may have a different condition compared to a part of the building envelope not in the shade. Therefore, the system may advantageously take into account, when determining the condition, the dimensions, orientation and/or geographic location of the building envelope. Furthermore, the system may

advantageously take into account, when determining the condition, the geographical location of the building envelope.

In an embodiment of the invention, the presentation unit is a display unit. This provides an easy way of implementing a presentation of the condition.

Furthermore, the display unit provides an advantageous way of visually displaying the condition.

In an embodiment of the invention, the presentation unit is configured for providing a report. The report may be provided through the use of a printer. The report provides an advantageous way of providing the condition for other uses.

In an embodiment of the invention, the condition is one or more of the group of an insulation value, a maintenance condition, degradation and/or deterioration condition or a pollution condition of the building envelope.

A building envelope typically has an insulation value. The insulation value determines the amount of energy input on the inside of the building that is needed for maintaining a particular temperature difference across the building envelope. The insulation value is therefore a factor for determining the building environmental efficiency. The higher the insulation value, the less energy input into the building is needed for maintaining the temperature difference across the building envelope or in other words the inside and outside of the building. Typically, the better insulation values are in balance, the less thermal bridges arise and less extra impact arises which promotes the degradation process. The temperature difference may be due to cooling or heating the inside of the building compared to the outside temperature.

An insulation value may be expressed in a U-value, a K-value and/or Rc- value, which expresses the amount of warmth per second, per square meter and per degree Celsius temperature difference between opposite sides of a building envelope. The U-value may be typed as a warmth conductance coefficient. Alternatively, the insulation value of a material may be expressed in a Rd-value and the insulation value of a building envelope as a whole or part of the building envelope may be expressed in an Rc-value. Alternatively, the insulation value of a material may be expressed in an R- value, C-value or Lambda-value. Alternatively, the insulation value of a building envelope may be expressed in a K-value.

The insulation value typically decreases over time. As the insulation value decreases, it may be, at a certain moment in time, necessary to restore or upgrade the insulation value by maintaining the building envelope. Furthermore, it may be, at a certain moment in time, necessary to rebuild and/or renovate the building envelope. Therefore, the insulation value advantageously specifies a condition of the building envelope and/or fagade.

A maintenance condition may be defined as the time up to the next maintenance of the building envelope. A maintenance condition may be defined as a state of the building envelope, such as a state of a building block, a building element or building unit. A state may be the hardness of a layer in the building envelope and/or fagade, the colour of the building envelope, the amount of crumbling of the building envelope, the waterproofness or any other state of the building envelope. As the maintenance condition typically decreases or degrades over time, determining the maintenance condition may provide the advantage of optimizing the use of building material.

A degradation and/or deterioration condition may be a value expressing the degradation and/or deterioration of the building envelope and/or fagade, such as the decline of an insulation value. Another example of a degradation condition may be the waterproofness of the building envelope. Another example of the degradation condition may be energy efficiency of the building envelope.

A pollution condition may be the amount of dirt on glass windows indicating that these windows need to be cleaned. An indicator for the amount of dirt on a glass surface, such as a glass window, PV-panels and/or PVT-panels, may be the

transparency or change in transparency of the glass surface. Glass surfaces may also age, which may influence the transparency of the glass as well and thus the

degradation and/or deterioration condition. Furthermore, a pollution condition may be the amount of dirt in a gutter of the building envelope. If the amount of dirt exceeds a certain limit, the dirt may block the gutter, thereby minimizing the function of the gutter. In an embodiment of the invention, the condition is a parameter with a continuous range of values. Although the condition is typically presented digitally, which has a discrete character by definition, the condition may be presented with such accuracy that it may be perceived as a continuous range. This provides the advantage of highly accurate measurement and thus a highly accurate insight in the condition and the condition change over time.

In an embodiment of the invention, the condition is a parameter with a predefined amount of settings, such as three settings, such as a traffic light or API. The condition may be presented as a value with very limited amount of states or steps. This condition may advantageously be easily read and interpreted by a person being presented with the condition via the system.

In an embodiment of the invention, the system comprises a storage for storing a predefined degradation parameter, wherein the processing unit is configured for determining the degradation condition based on the difference between the predefined degradation parameter and the measurements. This embodiment provides the advantage of being able to adjust factory determined parameter of a building unit. Furthermore, this embodiment provides the advantage of checking and/or adapting a maintenance plan for a building envelope. The maintenance plan may comprise specific maintenance plans for building units or groups of building units, typically groups of building units comprising the same material or being made of substantially the same material.

Another advantage of this embodiment is as the factory determined parameters are optimized, the adjusted factory parameters provide a more reliable input for a planning, such as a backcasting planning. Furthermore, the maintenance plan may be further optimized as the adjusted factory parameters provide an enhanced prediction of future maintenance.

According to another aspect of the current invention, an assembly for measuring a condition, comprising: a building having a building envelope; and a system according to any of the preceding claims, wherein the plurality of sensors is arranged to the building envelope; wherein the presentation unit presents the condition of the building envelope, providing advantages such as mentioned for the system.

In an embodiment of the invention, the system of the assembly measures continuously and/or real-time providing the advantages as mentioned for the system.

In an embodiment of the invention, the building envelope of the building of the assembly comprises building units having a building unit parameter and wherein at least part of the plurality of sensors is arranged to one or more of the building units for measuring a building unit parameter providing the advantages as mentioned for the system.

According to another aspect of the current invention, a method for measuring a condition of a building envelope, comprising the steps of: receiving measurements of a plurality of sensors arranged for measuring one or more

parameters of the building envelope; determining the condition based on the received measurements; and presenting the condition. The method may provide the same advantages as mentioned for the system.

In an embodiment of the invention, wherein the determining step is further based on a type of material used for the building envelope providing the advantages as mentioned for the system.

In an embodiment of the invention, the determining step is further based on dimensions, an orientation and/or a geographic location of the building envelope providing the advantages as mentioned for the system.

In an embodiment of the invention, the method comprises the steps of:

- retrieving a predefined degradation parameter from a storage; and

- calculating the difference between the predefined degradation parameter and the measurements;

wherein the degradation condition is based on the difference providing the advantages as mentioned for the system.

According to another aspect of the current invention, a computer program product comprising a computer readable medium having computer readable code embodied therein, the computer readable code being configured such that, on execution by a suitable computer or processor, the computer or processor is caused to perform the method of any of the claims or mentioned in the description.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be apparent from and elucidated further with reference to the embodiments described by way of example in the following description and with reference to the accompanying drawings, in which:

Figure 1 schematically shows a system for measuring a condition of a building envelope according to an embodiment of the current invention;

Figure 2 schematically shows a fragment of a fagade of a building; Figure 3 schematically shows an assembly for measuring a condition according to the current invention;

Figure 4 schematically shows a method for measuring a condition of a building envelope according to the current invention; and

Figure 5 schematically shows an embodiment of a computer program product, computer readable medium and/or non-transitory computer readable storage medium according to the invention.

The figures are purely diagrammatic and not drawn to scale. In the figures, elements which correspond to elements already described may have the same reference numerals.

LIST OF REFERENCE NUMERALS

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following figures may detail different embodiments. Embodiments can be combined to reach an enhanced or improved technical effect. These combined embodiments may be mentioned explicitly throughout the text, may be hint upon in the text or may be implicit.

Figure 1 schematically shows a system 100 for measuring a condition of a building envelope according to an embodiment of the current invention. The system comprises a first sensor 110, a second sensor 120, a processing unit 160 and a presentation unit 170. The system may comprise a third sensor 130, a fourth sensor 140 and a fifth sensor 150. The first sensor may be a sensor for measuring the thermal conductivity or insulation value. The first sensor may comprise a first part 111 and a second part 112 arranged on both sides of a wall 10, which is part of a building envelope. The sensor further may comprise an aggregator 115. The first and second part are connected to the aggregator via a first and a second part signal 113, 114 respectively. The signals may provide energy to the parts, control signals to the parts and/or measurement signals to the aggregator.

The second sensor may be a sensor for measuring the amount of dirt on a glass window. The second sensor may comprise a first part 121 and a second part 122 arranged on one side of a glass window 20. The sensor further may comprise an aggregator 125. The first and second part are connected to the aggregator via a first and second part signal 123, 124 respectively. The signals may provide energy to the parts, control signals to the parts and/or measurement signals to the aggregator. The first part of the sensor may emit light, which reflects on glass and is received at the second part. In case the glass window is dirty, the light will be scattered instead of reflected on the glass. Thus, if the glass window is dirty, no or less light will be received at the second part, which may be sensed by the second part of the sensor.

Other sensors are envisioned for the current invention. Another type of sensor may be a sensor for measuring the light exposure, such as sunlight exposure, such as ultraviolet light exposure, of the building envelope. Another type of sensor may be a sensor for measuring the delamination of a coating layer, such as a paint layer, of the building envelope. Coating layers are particularly applied on parts of the building envelope having a wood, aluminium or bitumen base. Another type of sensor may be a sensor for measuring the presence and size of openings, such as a crack or a dilatation, in the building envelope. Another type of sensor may be a sensor for measuring the amount of ventilation of, transmission losses of, condense on and/or rain on the building envelope. Another type of sensor may be a sensor for measuring the gloss level of a surface of the building envelope. Another type of sensor may be a sensor for measuring decolouration, such as the level of dull, dim, mat or pale, of a surface of the building envelope. Another type of sensor may be a sensor for measuring the level of opaque or transparency of a building envelope. Another type of sensor may be a sensor for measuring the amount of solvent, menstruum, diluent, dissolvent or plasticizers in the building envelope. Another type of sensor may be a sensor for measuring the atmospheric pollution, such as UV radiation and/or ozone, directly next to the building envelope. Another type of sensor may be a sensor for measuring the potential difference over a part, such as over metal parts of the building envelope

A building envelope may be defined as a building shell forming the outside of the building. A building envelope may be defined as an outer layer of the building. A building envelope may for example comprise a wall, such as a brick, concrete wall or cement wall. A building envelope may for example also comprise a glass window and a window frame.

Sensors are particularly applied to a part of the building envelope. Further, the arrangement or positioning of the plurality of sensors may be used for providing a more accurate condition of the building envelope. Further, the processing unit may use the knowledge of the arrangement or position of the plurality of sensors for more accurately determining the condition.

The building envelope may comprise building units. A building unit may be such a part of the building envelope with a particular parameter, which may be measured by a sensor. The building envelope, building element or building envelope unit may comprise glass, steel, aluminium, zinc, masonry, brickwork, stonework, PV panels, PVT panels, wood, plastics, bitumen, tar, pitch, mud, earth or any other material suitable for use in a building envelope, building elements and/or fagade. Also, more exotic building envelope materials such as roofs comprising grass and bush are envisioned by the inventor.

The processing unit receives all the measurements of the plurality of sensors. The measurements may be received via analogue or digital signals. The received measurements may be already pre-processed, only stabilized or raw measurements signals. The signals between the sensors and the processing unit may be communicated via wire, wireless or a combination. The processing unit typically comprises a microprocessor, processor or computer. The microprocessor, processor or computer is typically loaded with a computer program product, such that, on execution, the microprocessor, processor or computer is caused to perform a method mentioned in the description or claims.

The processing unit determines a condition 165 of the building envelope based on the received measurements. The condition may be quantitative and/or qualitative. In case of a quantification, the condition may be a single value forming the condition or group of values forming the condition together. In case of a qualification, the condition may be expressed in good, moderate, bad and very bad. Good means no action needed, moderate means you may take action, but it is not necessary, bad means action is needed and very bad means immediate action is needed. Also, in case of a qualification, the condition may be expressed in different aspects, which may be rated differently. For example, good for the north part of the building envelope and moderate for the east part of the building envelope.

An example of a condition is the delamination of a layer of the building envelope. Another example of a condition is the decolouration of a surface of the building envelope. Another example of a condition is the thermal conductivity or insulation value of the building envelope. Another example of a condition is the amount of dirt or filth on the building envelope. Another example of a condition is the

susceptibility to deterioration of the building envelope, for example due to cracks, the amount of ventilation of, transmission losses of, condense on and/or rain on the building envelope. Another example of a condition is the gloss level of a surface of the building envelope. Another example of a condition is the deterioration of the building envelope based on the level of opaque or transparency of a building envelope. Another example of a condition is the deterioration of the building envelope, which may be based on the amount of solvent, menstruum, diluent, dissolvent or plasticizers in the building envelope. Another example of a condition is the cleanness of the building envelope based on the atmospheric pollution directly next to the building envelope. Another example of a condition is the amount of deterioration of the building envelope based on the potential difference over a part, such as over metal parts of the building envelope. Another example of a condition is the structural integrity of the building envelope based on the measurements of the building envelope.

The presentation unit receives the condition from the processing unit.

Typically, the presentation unit is a display connected to the processing unit, being a computer. Alternatively, the presentation unit may be a remote display remote from the processing unit. The display may present a dash board. Further, the presentation unit may be a printer printing a report comprising the condition. Further, the presentation unit may be a software interface, such as an API. Other means of communicating the condition to an operator operating the system are envisioned by the inventor.

Based on the presented condition, maintenance of the building envelope may be scheduled. As the building envelope may deteriorate over time, such as for example a coating layer, such as a paint layer, the deterioration may cause other parts of the building envelope to be affected by the deterioration, such as the base material under a coating. As the deteriorated part of the building envelope is removed, repaired and/or replaced, further deterioration of the building envelope is prevented, thereby optimizing the use of the building materials in the building envelope. Furthermore, if a part of the building envelope is removed, repaired and/or replaced at the end of its lifetime, thus not too soon, this part of the building envelope is used to its maximum useful life expectancy, thus not wasting this part of the building envelope while it is still able to carry out its function, such as for example a coating layer protecting a base material under the coating.

As another example of maintenance, a plastic window frame typically loses its plasticizer over time due to natural break down enhanced by UV-light, ozone and/or diffusion. These window frames may become brittle and/or may lose its insulation value or structural integrity. Therefore, these window frames should be replaced after they do not fulfil their function anymore.

As another example of maintenance, joints in masonry, such as grouts, or surface of the masonry, such as plaster becomes brittle, starts cracking and/or drops out of the building envelope. This deterioration reduces the stability of the building envelope and/or reduces the insulation value. Furthermore, it may cause hazardous situations to people close to the building envelope. As part of the maintenance, the grout and/or plaster of the building envelope may be restored. As part of the

maintenance, together with the grout several bricks or blocks may be replaced.

As another example of maintenance, a protentional difference may develop over concrete iron and/or rebar comprised inside the building envelope. Part of the concrete iron and/or rebar may get exposed to the outside due to deterioration of the building envelope which may enhance the development of a potential difference. A potential difference may enhance the development of rust in the concrete iron and/or rebar.

Monitoring if maintenance needs to be done may advantageously be done continuously or real-time. In the context of the current application, real-time and/or continuous measurement is doing a measurement multiple times a month, preferably, multiple times a week, more preferably multiple times a day, most preferably once or multiple times an hour. The condition may therefore not only take into account the current status of the sensed parameter measured by the sensor, but also the rate of change of the sensed parameter. Furthermore, the processing unit may take into account the ecological environment, such as the weather, when determining the condition. Furthermore, the processing unit may take the time of year into account when determining the condition. For example, if the parameter is barely within limits at the start of autumn, the condition may indicate that maintenance is to be done before winter starts. As another example, if the parameter is barely within limits at the end of spring, the condition may indicate that maintenance is to be done somewhere in summer or start of autumn.

Figure 2 schematically shows a fragment of a fagade 400 of a building. The fragment forms part of a building envelope. The fragment of the fagade comprises a fragment of a window glass 410, a fragment of a window frame 420, a fragment of a wall 430, a fragment of concrete 440 and a fragment of plasterboard 450.

The window glass 410 typically has a transparency that degrades over time. Furthermore, the window glass has an insulation value that degrades over time. The window glass may be double or triple glass providing typically a higher insulation value as a single window glass. The double or triple window glass typically traps a gas, e.g. an inert gas, typically at a low pressure, such as a vacuum, between the windows for providing a large insulation value. This gas may diffuse over time. Also, the low pressure may be lost over time. The diffusion and loss of under pressure result in a loss of insulation value of the window glass. The decline in insulation value is an indicator of the degradation condition of the window glass. The decline in insulation value may be measured with an ultrasonic senor or with an IR-sensor.

The window glass collects pollution over time. The pollution degrades the transparency of the glass. Transparency may be seen as a condition that degrades over time. Furthermore, pollution, such as dirt, on a window glass causes enhanced degradation of the insulation value of the glass window. Transparency of the window glass may be measured with an ultrasonic sensor or with a light sensor.

The window frame 420 may comprise wood, metal, such as aluminium, iron or steel. Wood typically rots over time if not protected with a protective layer. This protective layer should be checked and maintained over time. If the protective layer is not maintained, the protective layer will lose its function and the wood will start to rot after the protective layer has lost its protective capabilities. The amount of wood rot or the status of the protective layer is an indicator of the degradation condition of the window frame. The protective function of the protective layer may be measured, e.g. the thickness of the protective layer, with the use of an ultrasonic sensor or an UV sensor. The protective function of the protective layer may be measured indirectly by measuring the moist in the window frame with the use of an ultrasonic sensor or a hygro sensor.

A window frame comprising metal may comprise features preventing cold bridges in the window frame. These features are typically rubber strips integrated in the window frame, as rubber or the like have good insulating properties. On the other hand, the window frame also needs stiffness properties provided by the metal parts in the window frame. These features typically enhance the insulation value of the window frame, but also degrade over time. If these features degrade over time, the insulation value of the window frame will decrease. The degradation of a window frame

comprising metal may be measured with the use of an ultrasonic sensor or magnetic induction sensor. The degradation of a window frame comprising metal may be measured indirectly by measuring the gloss of the window frame with the use of an ultrasonic sensor or magnetic induction sensor.

A window frame may comprise plastic. Plastic may degrade under the influence of sunlight, precipitation, such as rain, snow and hail, temperature swings or other weather influences. The insulation value of plastic will degrade as well under these influences. The degradation of a window frame comprising plastic may be measured with the use of an ultrasonic sensor, UV sensor or PID sensor. The degradation of a window frame comprising plastic may be indirectly measured by measuring the gloss of the window frame with the use of an ultrasonic sensor and a UV sensor.

The wall 430 is typically an outer wall forming part of the building envelope. The degradation condition of the wall may be indicated with the insulation value of the wall. The wall may comprise a wall cavity 431. The wall cavity typically enhances the insulation value of the wall. The wall cavity may comprise an insulation material. This insulation material typically enhances the insulation value of the wall even further. This insulation material typically degrades over time. The insulation value of the insulation material may be measured with an ultrasonic sensor, hygro sensor or infrared sensor.

The concrete 440 may be used in a wall for its insulating property. The concrete may be used in a wall for its compressive strength. To enhance the

compressive strength of a concrete wall, the concrete may be reinforced with steel. Other uses are envisioned by the inventor. These properties may degrade over time contributing to a degradation condition of the concrete. Concrete will typically degrade under the influence of carbonation. Carbonation of concrete may be measured with an electrostatic sensor of a hygro sensor.

The plasterboard 450 may have a fire-retardant effect. The fire-retardant effect comes mainly from the water, specifically crystal water, contained in the plasterboard. This water will typically evaporate over time, decreasing the fire-retardant property of the plasterboard. The water content may be measured with the use of an infrared sensor.

Although not shown, the building envelop may comprise solar panels. Solar panels degrade over time. Degradation over time of a solar panel may be expressed in the decline of effectivity of converting solar energy in electrical energy. The solar panel may also have an insulating effect, when shielding e.g. sunlight from heating the building, which may degrade over time. The degradation of a solar panel may be measured with an infrared sensor. The degradation of a solar panel may also be measured indirectly by measuring the pollution on the solar panel with the use of an infrared sensor.

The degradation condition of a building unit may be the insulation value of the building unit. The degradation condition of a building unit may be the insulation value measured by multiple sensors combined such that one insulation value is presented. This may provide the advantage of having a more accurate insulation value. This may also provide the advantage that the insulation value may be measured over a larger range, where one sensor is suitable for one part of the range and another sensor for another part of the range. The multiple measurements may also provide a combination of these advantages.

The degradation condition of a building envelope may be an aggregate of the insulation values of multiple building units. The degradation condition may be the inverse of the addition of the inverse insulation values of the individual building units making up the building envelope. In formula form:

C _T = Total degradation condition

C _n = insulation value of building unit n

Figure 3 schematically shows an assembly 200 for measuring a condition according to the current invention. The assembly comprises a first building 201 and may comprise a second building 202. The first and the second buildings comprise respectively first and second building envelopes. The assembly further comprises a system according to the current invention. The system comprises a plurality of sensors. A part or all of the sensors may be arranged to the first building envelope and/or second building envelope for measuring one or more parameters of the building envelope. The system further comprises a processing unit 260 connected with the plurality of sensors 205, 206. The system further comprises a presentation unit. The presentation unit receives a condition 265 from the processing unit.

The building comprised in the assembly may be a home, flat, apartment complex, warehouse, skyscraper, industrial hall or combination of these. The system in the assembly may be arranged to an existing building. Alternatively, the system in the assembly may be arranged to a newly constructed building. Alternatively, the system in the assembly may be arranged to a reconstructed or renovated building.

Figure 4 schematically shows a method 300 for measuring a condition of a building envelope according to the current invention. The method starts with the step of receiving measurements of a plurality of sensors arranged for measuring one or more parameters of the building envelope. The method continuous with the step of determining the condition based on the received measurements. Thereafter the method continuous with the step of presenting the condition.

A fagade of a building envelope may comprise multiple building units, building elements. An example of a building unit may be a glass of a window.

Alternatively, the glass may be of any other part of the building envelope, not used as window, such as of a solar panel.

The transparency of glass degrades over time. The insulation value of glass also degrades over time. Typically, the change of transparency of glass and the degradation of insulation value of glass have a correlation, typically a high correlation.

The transparency of glass may be measured with a light sensor or infrared - IR- sensor. The light sensor may measure the transparency directly or indirectly by, for example, measuring reflection and absorption of the glass. The transparency may also be measured with the use of an ultrasonic sensor. The ultrasonic sensor measures the change in the structure of the glass, which also may correlate to the insulation value.

The insulation value of glass may be measured by placing a temperature sensor on both sides of the glass. The insulation value of glass may also be measured with an infrared sensor. These measurements although accurate only provide a result as long as there is a temperature gradient over the glass. Hence, combining a temperature or an infrared sensor with a light sensor or an ultrasonic sensor provides the advantage of being able to measure the insulation value under all conditions.

Furthermore, a building unit may comprise double glass. Typically, the space between the double glass is filled with a gas, such as Argon. Argon contributes to the insulation value of the building unit. The loss of Argon over time causes the building unit to lose its insulation value. The loss of Argon may be measured with an ultrasonic sensor. Typically, the ultrasonic sensor measures the insulation value of the double glass and the gas filled space between the glass.

Another example of a building unit may be a window frame of a window. Especially a window strip, also known as draft strip or weather strip, will degrade over time resulting a decreasing insulation value. The degradation of a windows strip may be measured with the use of a Volatile Organic Compounds -VOC- sensor or

Photoionization Detector -PID- sensor.

Furthermore, the window frame may comprise a cold trap preventing heat to leak or transmission losses through the window frame, thereby increasing the insulation value. A cold trap typically degrades over time. The degradation of the cold trap in a window frame may be measured with an ultrasonic sensor, temperature sensor or PID sensor.

Another example of a building unit may be roof insulation. The insulation value of roof insulation also degrades over time due to warping or bulging. Also, after some time moist may build up in the roof insulation also degrading the insulation value. The moist build up may be due to warping and bulging of the building unit, building envelope, building elements. The loss of insulation value in roof insulation may be measured with the use of an ultrasonic sensor and/or a hygro-sensor and/or an IR- sensor and/or a PID sensor.

Another example of a building unit may be two planes of stone bricks with a cavity wall in between. The insulation value of especially the cavity wall may decrease over time. The insulation value may be measured with the use of an ultrasonic sensor, and/or a hygro-sensor or IR-sensor and/or a PID sensor.

Another example of a building unit may a panel, for example a panel of wood or metal. Typically, the panel is covered by a protective layer or coating, such as a protective layer of paint. A protective layer of paint should have the right thickness. A coating which is too thin may not provide the protective properties, while too thick may cause cracks or even exfoliation of the protective layer leaving the underlying panel unprotected. An unprotected panel will typically degrade at a high rate. The same applies when the panel is composed from e.g. a metal.

A protective layer may be measured with the help of an ultrasonic sensor. The ultrasonic sensor may be used to distinguish multiple layers, which may be multiple protective layers to interpret the measured parameters into a degradation condition. Alternatively, the protective lay may be measured with the help of a UV- sensor, sensing the transparency of the coating for UV. The thickness and degradation of the coating have an influence on the UV measurement.

If the panel or the coating is composed of ferromagnetic material, a magnetic induction sensor may be used. For example, the non-ferromagnetic coating having a thickness separates the magnetic induction sensor from the ferromagnetic material, which separation may be measured by the magnetic induction sensor.

If the panel or the coating is composed of non-ferromagnetic material, an Eddy-current sensor may be used. For example, the non-metal coating having a thickness separates the Eddy-current sensor from the non-ferromagnetic material, which separation may be measured by the Eddy-current sensor.

As another example, if the panel is made of metal, the panel may show metal fatigue over time. Metal fatigue may be measured with an ultrasonic sensor.

Another example of a building unit may be an element made of a synthetic material, such as a plastic material. Plastic materials tend to become weak and brittle over time. Furthermore, plastic materials tend to lose insulation value over time. The weakness and brittleness and loss of insulation value have a correlation. The weakness and brittleness may be measured with an ultrasonic sensor or UV-sensor.

As another example, the panel may be of a fire-retardant material. The fire- retardant property may be lost over time. For example, plasterboard is fire-retardant due to the amount of water, preferably crystal water, held in the board. The fire- retardant property may be measured with the use of an infrared sensor and/or a temperature sensor and/or an IR-sensor and/or an ultrasonic sensor.

Another example of a building unit may reinforced concrete. Reinforced concrete comprises a metal framework inside, that may rot under the influence of moist in the concrete. The concrete rot or carbonation may be measured with the use of an electrostatic sensor and/or a hygro-sensor and/or an ultrasonic sensor.

Other examples of building units from which a degradation parameter may be measured contributing to a condition are envisioned by the inventor.

Figure 5 schematically shows an embodiment of a computer program product, computer readable medium and/or non-transitory computer readable storage medium 1000 having a writable part 1010 including a computer program 1020, the computer program including instructions for causing a processor system to perform a method according to the invention.

Examples, embodiments or optional features, whether indicated as non- limiting or not, are not to be understood as limiting the invention as claimed. It should be noted that the figures are purely diagrammatic and not drawn to scale. In the figures, elements which correspond to elements already described may have the same reference numerals.

It will be appreciated that the invention also applies to computer programs, particularly computer programs on or in a carrier, adapted to put the invention into practice. The program may be in the form of a source code, a code intermediate source and an object code such as in a partially compiled form, or in any other form suitable for use in the implementation of the method according to the invention. It will also be appreciated that such a program may have many different architectural designs. For example, a program code implementing the functionality of the method or system according to the invention may be sub-divided into one or more sub-routines. Many different ways of distributing the functionality among these sub-routines will be apparent to the skilled person. The sub-routines may be stored together in one executable file to form a self-contained program. Such an executable file may comprise computer-executable instructions, for example, processor instructions and/or interpreter instructions (e.g. Java interpreter instructions). Alternatively, one or more or all of the sub-routines may be stored in at least one external library file and linked with a main program either statically or dynamically, e.g. at run-time. The main program contains at least one call to at least one of the sub-routines. The sub-routines may also comprise function calls to each other. An embodiment relating to a computer program product comprises computer-executable instructions corresponding to each processing stage of at least one of the methods set forth herein. These instructions may be sub- divided into sub-routines and/or stored in one or more files that may be linked statically or dynamically. Another embodiment relating to a computer program product comprises computer-executable instructions corresponding to each means of at least one of the systems and/or products set forth herein. These instructions may be sub- divided into sub-routines and/or stored in one or more files that may be linked statically or dynamically.

The carrier of a computer program may be any entity or device capable of carrying the program. For example, the carrier may include a data storage, such as a ROM, for example, a CD ROM or a semiconductor ROM, or a magnetic recording medium, for example, a hard disk. Furthermore, the carrier may be a transmissible carrier such as an electric or optical signal, which may be conveyed via electric or optical cable or by radio or other means. When the program is embodied in such a signal, the carrier may be constituted by such a cable or other device or means. Alternatively, the carrier may be an integrated circuit in which the program is embedded, the integrated circuit being adapted to perform, or used in the performance of, the relevant method.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or stages other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.