Copyright 2014 National Flood School

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2 DryApp has been developed by the National Flood School. It has been designed with multiple users and uses in mind. It can assist Restoration Technicians and Builders in calculating the number of dehumidifiers they need when drying a property, as well as informing them whether or not open drying would be appropriate. Surveyors, Insurance Claims Handlers and Loss Adjusters/Assessors, as well as Home Owners, also use DryApp to help verify whether their chosen Restorer is drying their property most effectively. However, it should be remembered that DryApp can only provide an indication of the most effective drying regime. This is because individual property circumstances (such as the type of building construction, and the ability for air to circulate freely throughout the property) are key to drying optimisation. The National Flood School (based in Farnham, Surrey) has been training Flood Restoration Professionals for over 25 years with unparalleled success. Their training, which follows the standards and syllabus of the internationally recognised Institute of Inspection Cleaning and Restoration Certification (IICRC), benefits from being delivered by a team with over 80 years of experience in Flood Restoration. Unique in Europe is the National Flood School s Flood House a purpose built single-storey habitable property which is regularly flooded with over 7000 litres of water to simulate a typical top-down flood. Students use the theoretical knowledge they have gained in the classroom to dry the property, gaining essential handson practical experience. As well as training students, the National Flood School offers expert consultancy in Flood and Fire Damage Restoration throughout the UK and abroad (with clients in Europe, Dubai and Thailand). UK based insurance companies often appoint the National Flood School to provide specialist advice in dealing with complex flood damage claims. With the wealth of knowledge and expertise available to the National Flood School, the development DryApp was a natural step in helping to improve the quality of restoration services provided throughout the UK.

3 CONTENTS 1 Getting Started with DryApp 2 Entering Property Details 3 Saved Data 4 Reports 5 Open Drying 6 About Dehumidifiers 7 About Air Movers 8 Glossary / Abbreviations 9 Example of an information leaflet for property owners/occupiers

4 1 Getting Started with DryApp a) Tap the DryApp icon on your Android mobile/tablet device to load the application. b) After loading DryApp, the first screen you ll see is the Main Menu (below). c) Tap the GPS satellite icon to refresh the weather status (supplied by the UK Met Office) for your current location. d) Tap Settings to set your details. e) Below shows the Settings Menu. Select Your Details to set your address (to receive PDF copies of DryApp reports).

5 f) After entering your address, click Save. g) You will then be returned to the Main Menu.

6 2 Entering Property Details a) You are now ready to start entering details of the property to be dried. Click Properties. b) You will now see your Property List. The first time you use DryApp the list will be empty. To add a new property click the + icon in the top right hand corner of the screen.

7 c) A blank Property details screen will be displayed. d) Enter the address of the property on the first line. Next, either enter the postcode of the property on the second line, or click USE GPS for the most accurate weather information for your location. DryApp will calculate the volume of the room automatically once you have entered the Width, Depth and Height of the room.

8 e) Use the tick boxes on the right-hand side of the screen to indicate where a room can be treated as one contiguous space. In the example below, the accommodation is open-plan, where the Kitchen and the Lounge/Diner can be treated as one large area. The tick-box and been checked against Lounge/Diner, indicating that it is to be linked to the room listed directly above it (i.e. the Kitchen). Once you have entered all the details of the rooms that need to be dried, click the NEXT/SAVE button, at which point the following screen will be displayed.

9 f) Enter the Relative Humidity and room Temperature readings for the first room displayed (in this case the Kitchen). Next, click on the Select Dehum button to display the following screen, and select the required dehumidifier from the available list. If the dehumidifier in use isn t listed, use one of the generic (Small, Medium, Large) specifications, or Add a new dehumidifier (see next section). Once you ve chosen your dehumidifier, click on the Select button.

10 g) If the dehumidifier you re using isn t listed in DryApp, simply enter the details in the boxes as shown below, and click Add. You can now select this dehumidifier. Once you have selected the dehumidifier for the first room of the property and saved this (by clicking the Save button), you can then repeat the process for any other rooms. To do so, click the reload/refresh icon in the top right-hand corner of the screen. This will display the list of available rooms. Note that in this example, the Lounge/Diner is greyed-out and cannot be selected. This is because we earlier linked this room to the Kitchen as the property in question is open-plan and therefore the two rooms can be treated as one. Also in this example, you will note the presence of a - sign under the Thursday, Friday and Saturday indicators. This shows that the use of Open Drying would have a neutral effect (i.e. it would neither improve nor worsen the drying environment). However, on Sunday and Monday the x shows that

11 the use of Open Drying would have a negative impact on drying the property (i.e. that it would worsen). But in the screenshot below you will see that everyday shows a tick symbol with a green background. This indicates that the conditions are ideal for Open Drying. 3 Saved Data Each time you visit the drying site you will update the environmental and drying conditions. By saving this data upon each visit, your reports will show the changes over time, providing an audit trail of your work. Clients should be reassured by the visible improvement in drying that is reported during each visit. 4 Reports From the Main Menu, select Send Reports. Then click on the property for which you wish to generate/send a report. This will automatically send the formatted report to the address that you recorded in section 1. f).

12 The following is an example of a typical DryApp report that will be ed to your chosen address. 5 Open Drying Open drying allows for the exchange of high humidity air (i.e. high levels of evaporated water vapour) within the structure, with low humidity air from outside the structure, or areas being dried. This method does not use mechanical dehumidification but uses or relies on enhanced air movement to increase the rate of exchange of air. In order for this technique to be truly effective, the outside conditions (humidity ratio) should be drier than the internal humidity ratio conditions. A building s security, occupant s preferences, heat loss and other influencing factors when opening up the structure to the outside should be taken into consideration. When outdoor air is cool but dry, heat has to be added to the internal structure to maintain an appropriate indoor temperature in relation to the relative humidity and humidity ratio to encourage evaporation to continue. Combination Drying System A combination drying system uses both open drying and mechanical dehumidification. This system can be used when the balance of a better drying environment between the outside and inside fluctuates and site specific conditions allow.

13 6 About Dehumidifiers DryApp is pre-configured with three generic refrigerant dehumidifiers, labelled Small, Medium and Large, and two generic desiccant dehumidifiers, labelled Small and Large. The capacities and power consumptions of these are described below. Refrigerant Dehumidifiers Generic Model Size Litres / Hour (moisture extracted) Kilowatts per Hour (power consumption) Small Medium Large Desiccant Dehumidifiers Generic Model Size Litres / Hour (moisture extracted) Kilowatts per Hour (power consumption) Small Large However, it should be remembered that these are generic examples only, and the physical size of the dehumidifier does not necessarily reflect its capacity or power consumption. It s important therefore to consider adding details to DryApp for the specific dehumidifier(s) that you are using in order to obtain optimal results from the application. It is envisaged that in most cases the generic models will satisfy most requirements. The following tables compare (using manufacturer s data) a number of products from different manufacturers in the conditions specified. Note that it is important to compare equipment on a likefor-like basis some manufacturers will publish performance data in different conditions 32.2 C and 90RH), and this will affect the equipment s performance significantly. When adding your own equipment to DryApp, ensure that you are using consistent data. Refrigerant Dehumidifiers Make / Model Litres / Day (@26.7 C and 60% RH) KiloWatts per Hour (power consumption) Weight (Kg) Dimensions (mm) W x H x D Arida 1500 P x 880 x 495 Capture 65L x 810 x 540 Dri Eaz x 830 x 500 Ebac CD x 550 x 350 Ebac Kompact x 615 x KP-GB Phoenix 200 Max LGR x 1016 x 543

14 Desiccant Dehumidifiers Make / Model Litres / Day KiloWatts per Hour Weight Dimensions (mm) (@20 C and 60% RH) (power consumption) (Kg) W x H x D Aerial ASE x 260 x 325 Aerial ASE x 323 x 360 Corroventa CTR x 275 x XT Corroventa CTR x 480 x XT Dri-Eaz DriTec PRO x 256 x 436 If you have an alternative model to those listed above please contact us for help with the calculations. If you are a manufacturer and would like your product included in the manual please contact us at information@nationalfloodschool.co.uk

15 Examples of Refrigerant and Desiccant Dehumidifiers Ebac CD35 Dri-Eaz Drizair 1200 Phoenix 200Max LGR Ebac Kompact 10240KP Capture 65L Aerial Desiccant Adsorption Dryer Corroventa Desiccant Adsorption Dryer

16 7 About Air Movers Whether relying on the weather for Open Drying of a property, or installing Dehumidifiers to achieve the same, it s important to achieve sufficient air circulation throughout the area to be dried. This ensures that enough dry air passes over wet surfaces to improve moisture extraction. Air Movers (also referred to as Turbo Fans) are key to achieving that aim. How many Air Movers? During the initial constant rate stage (refer to IICRC S500 Chapter 5, Psychrometry and Drying Technology) of drying, the increased rate of evaporation caused by Air Movers is directly related to the airspeed across the wet surface. Air Movers used during this stage should be set up so that continuous rapid airflow is provided across wet surfaces. The restorer should install Air Movers to deliver air along the lower portion of a wall and the edge of the floor, in a circular fashion. Air Movers should be installed at an angle (e.g ) that provides a constant, sensible, flow of air along the entire length of all affected walls. In addition, Air Movers should be added to direct flow across the open areas of the room or space if the size of the room or the presence of contents prevents sensible airflow across the entire floor surface. Air Movers should also be used to ensure circulation of air throughout the workspace as needed. To accomplish this, the restorer should install at least one Air Mover in each affected room or space, to include bay windows, hallways, rooms, cupboards, alcoves, etc. The restorer should also consider the addition of Air Movers to ensure airflow in and out of structural cavities (e.g. partition walls) and voids (e.g. under floorboards; lofts), whenever water has affected the materials in these spaces. In most residential and small commercial properties restorers should use one Air Mover for every 6-8 square meters of floor space, with a minimum of at least one Air Mover per affected space during the constant rate (initial) drying stage, to accomplish the required air flow. Restorers should add one Air Mover for each offset or inset that impedes airflow across wet surfaces (e.g. wall sections that are greater than approximately 50cm). In Class 3 water intrusion, restorers should add Air Movers to ensure sufficient airflow across wet surfaces (e.g. one Air Mover for every square metre of wet wall and ceiling surface). When wet flooring areas enter the falling rate drying stage, Air Movers should be reduced (e.g. one Air Mover for every 9 to 14 square metres), provided remaining wet or damp surfaces continue to receive sensible air flow, and circulation is maintained throughout the workspace. Refer to Chapter 5 Psychrometry and Drying Technology for more information on falling rate drying adjustments. Directed airflow is used in the restorative drying process to accomplish two objectives:

17 a) To circulate air throughout the workspace to ensure drier air continually displaces more humid air. Air should be circulated to all effected interstitial cavities, such as wall and ceiling voids, beneath cabinetry and underneath and within wood flooring systems. b) To direct air at material surfaces in order to displace the boundary layer of air and transfer energy to the surface moisture and materials. The boundary layer is a thin layer of humid air at the surface of wet or damp materials that should be continuously displaced to enhance evaporation.

18 8 Glossary / Abbreviations Dew Point (DP) Absolute Humidity (AH) Moisture Ratio (MR) Open Drying T ( C) RH (%) DP ( C) AH (g/m3) MR (g/kg) Delta AH (g/m3) Total Water Vapour Extraction Rate Dehums required Daily kwh GPS PDF The atmospheric temperature (varying according to pressure and humidity) below which water droplets begin to condense and dew can form. Relative humidity, expressed as a percent, measures the current absolute humidity relative to the maximum for that temperature. Specific humidity is a ratio of the water vapour content of the mixture to the total air content on a mass basis. A moisture ratio is a ratio that compares the mass or volume of air to the mass or volume of moisture contained in that air. In construction, it is an important consideration when designing a building for a certain climate. Open Drying means to leave a property open so that the atmosphere surrounding it will cause the liquid in it to evaporate (if conditions allow). Temperature (in Celsius) Relative Humidity Dew Point Absolute Humidity Moisture Ratio the amount of water in each Kg of air Total amount of water currently in the air to be extracted The rate at which the chosen commercial dehumidifier will remove water from the atmosphere in optimal conditions. The number of commercial dehumidifiers (of the size and specification selected) required drying the property in the stated environmental conditions. The approximate total daily power consumption (in Kilowatt Hours) of the number of dehumidifiers required to dry the property in optimal conditions. The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. PDF (Portable Document Format) is a file format for capturing and sending electronic documents in exactly the intended format. PDF documents are most commonly read using Adobe Acrobat/Reader.

19 9 Example of an information leaflet for property owners/occupiers When undertaking the drying of a property it is important for the client/occupants to be consulted about, and involved in, the process. The following text (freely available from the PAS64 publication) may be used to produce a leaflet that will help to keep the client informed of the process. Mitigation and recovery of water damaged buildings Code of practice (PAS 64) Information leaflet for property owners/occupiers Overview PAS 64 is a BSI Code of Practice. It provides guidance on best practice on how to mitigate and restore water damaged buildings. This leaflet gives information to a property owner or occupier on what they can expect from any Restoration Company who follows this Code of Practice. It also gives details on the various methods and equipment that might be used to dry a building. Why is it important to deal with water damage to a building? Not dealing with water damage to a building in the correct way can lead to: additional health risks to its occupants, employees and visitors; repair costs increasing; secondary damage occurring; the value and usefulness of the building decreasing. What are the steps involved in the restoration? This will differ depending on the nature of the damage and other factors but typically your Restoration Company will carry out the following: 1) Initial inspection The restorer will gather information to help them decide on the best way to dry and/or clean the building. They will consider: the building type, construction materials and build techniques; the source and extent of the water damage; relevant information regarding the health, safety and wellbeing of occupiers. It may be necessary for emergency mitigation works to be carried out to limit further loss, including removal of standing water and the control of harmful contaminants in the building. 2) Drying goals If possible the Restorer will take a reading from an unaffected area as this will help them to establish what is known as the drying goal. They should also measure moisture content from the air inside and outside of the building and from structural materials that have been affected. This will help them to decide on the most appropriate drying method. 3) Cleaning goal The Restorer should establish a target cleanliness for the affected structural materials, contents, and/or the

20 indoor environment (air quality) being cleaned. This is known as the cleaning goal. Sometimes there is no need for cleaning to be done. 4) Deciding on the best approach to dry the property The Restorer will consider a number of factors when deciding how to dry the building: indoor and outdoor temperature and humidity; potential risks to employees, visitors and occupiers; potential security risks of leaving doors/windows open to assist drying; the environmental impact of the drying methodology; the availability of sufficient power; the predicted time it will take to reach the drying goals. 5) Ongoing monitoring The Restorer will monitor that the drying approach they have chosen is working. They should do this by checking the moisture levels at regular intervals. They do not always need to visit the building to do this as some equipment allows this monitoring to be done remotely (they should inform you if this is the case). If the building is not drying as expected it might highlight that there is another unknown cause of the water damage and/or that the drying method being used should be changed. Both of these scenarios are relatively rare. The Restorer should carry out a final completion inspection to establish that the drying goals have been met (e.g. the building is dry ). Documentation The Restorer should maintain documentation, including: internal temperature and humidity readings taken on each visit; moisture records for the affected structural materials, including drying goals and moisture content on completion; scope of works and any details which may influence the drying programme; contents and personal property inventories; detailed work log/diary (including decision making log, evidence of biological assessments, pre-incident conditions); equipment logs; site specific risk assessment documentation. Drying methods and systems Open drying system Ventilation is increased within a building, which can be done by simply opening windows. For this to work the outside air should be warmer and drier than the inside air. Closed drying system All windows and doors are shut and dehumidification equipment is installed to remove and control the evaporated moisture. Combination drying system This is where the use of an open drying system is combined with the use of mechanical dehumidification equipment. This system is typically used when conditions change resulting in the outside of the building not always being drier than the inside. Air exchange and heat drying system Equipment is used to increase the temperature of the indoor air helping to improve the rate of evaporation from wet structural material, which in turn is extracted from the building.

21 The warmer air is typically heated and circulated using machinery. The heated air absorbs the evaporated water from the wet structural materials. This is then either pumped out of the building or put through machinery which removes the extra water. Mechanical dehumidification equipment Refrigerant dehumidifiers The internal air is cooled below its dew point, which results in condensation appearing on the dehumidifier s internal evaporation coils. Water is then collected and removed from the area being dried, either by automatically pumping it away from the machine, or through containers being removed by hand. Desiccant dehumidifiers The damp internal air is blown through a desiccant material; this removes moisture by direct absorption and vapour pressure differences. The machine has two outlets; one which blows very dry air back into the building and a second, which blows very wet air out of the building. Water is not collected in its liquid form but is extracted from the area being dried via air movement. Convectant dehumidifiers The temperature in the room is increased by re-circulating the room s air through the machine s heating system. Once the internal air has reached a pre-defined temperature or if the relative or specific humidity reaches pre-defined levels, the machine switches to exhaust mode expelling wet air to the outside. Air movement Increasing air movement over the surface of a wet structural material encourages evaporation of the moisture within. Air movement also encourages turbulence within the area being dried, which can make drying equipment and techniques more effective. Heating equipment When the normal heating system in the building does not work or is insufficient, a secondary heat source may be needed. This is to both achieve the required drying conditions and to accelerate the evaporation of moisture from the structure. Heating systems may also be used to target specific troublesome drying areas as heating the building material directly will encourage evaporation. However, heating alone may be dangerous as uncontrolled evaporation can lead to secondary damage to the building. Target drying Sometimes a wet wall in a single room is the only area that has been damaged. If so, it may be preferable to just dry the air close to the affected wall. This is done by containing the area being dried by using plastic sheeting or specially designed materials, which are attached to the wall or targeted area. It is important that you follow all instructions the Restorer gives you on how and when to use the equipment they install. Not doing so may result in the restoration process taking longer and/or further damage occurring to the building.