Research · The advisory and building-science practice of Saniservice
Written to be checked, not admired.
Scientific authority should withstand scrutiny. This section sets out how buildings behave in hot, humid climates, beginning with the Dubai International hourly climate record and the physics of the cooled room, and explains the methods, assumptions and evidence behind the practice's work. Every figure is tied to a named dataset; every model states what it does not compute.
Dedicated to Jon Honesto de Castro (JV), co-founder and first Director of this practice.
Each note names its reviewer and its data.Measure · State · Verify
Science for air-conditioned buildings in a hot, humid climate.
Much of the published indoor science comes from cold climates, where the moisture to manage is made indoors and must be kept out of cold walls. In the Gulf the direction is reversed: the moisture comes from outside. At Dubai and Abu Dhabi the outdoor dew point is above 22 °C, the temperature of a cool air-conditioned room, in about one hour of every four, and any surface cooled below that dew point is a place for that moisture to condense. Our methods, our criteria and our research are built for that condition.
Thirty years of hourly dew-point data from six UAE weather stations, 1995 to 2024, with the station, period and source stated for every figure. Source: Meteostat (CC BY 4.0).
Assessment and laboratory records from homes and buildings across the UAE, built up over more than five years, and the reference our criteria are tested against.
The Saniservice Department of Microbiology: an in-house working laboratory for diagnosis and verification, with an EIAC-accredited (ISO/IEC 17025) partner laboratory where a result must carry formal certification.
The series
How buildings behave in hot, humid climates.
Research Notes are the practice's own studies: a question drawn from the field, a model or dataset that answers it, and a plain statement of what the answer does not cover. They are numbered, dated, technically reviewed, and revised in the open when a reader finds an error.
Six stations, one question: for what share of the year does the outdoor dew point exceed the set point of a cooled room? The series that gives the home page its "one hour in four", station by station, with the inland exception that makes the coastal claim precise.
Climate datasetWMO 41194 and five stations
Jon Honesto de Castro
The essays of the founder, preserved as he wrote them.
Jon Honesto de Castro, known to everyone as JV, co-founded Indoor Sciences with Franz B. Larsen, was its first Director and its daily spirit until his death. An architect by training and a scientist by temperament, he wrote the framework this practice still works by: the four elements, the building's skin and its circulation, and the conviction that a healthy indoor environment should not be assumed but measured. The essays below are his, published under his byline during his tenure. They are reproduced exactly as he wrote them, with their original dates; nothing has been edited, updated or re-attributed. Where later research has refined a figure, the Research Note carries the refinement and the essay stands as written.
Each Research Note is accompanied by a technical note that names the station, the source and its lineage, the window, the sample size and the statistical method, so that any consultant or project team can reproduce the figures. Methods the practice applies in the field are set out under Advisory.
TN-01 · Outdoor dew-point statistics
Dubai International, WMO 41194 (ICAO OMDB). Meteostat hourly bulk data, compiled from the NOAA NCEI Integrated Surface Database, decimal resolution, 1 January 1995 to 31 December 2024 (Meteostat, CC BY 4.0). June–September window, n = 84,959 hours: median 23.1 °C, 95th percentile 28.0 °C. Whole-year share of hours above 22 °C by station, six stations including the inland exception.
Dew point by the Magnus formula with the Alduchov–Eskridge coefficients (17.625, 243.04 °C, 610.94 Pa); surface relative humidity as the ratio of saturation vapour pressure at dew point to that at surface temperature, capped at 100%. Stated in full in Research Note 01.
Interpretation bands
Indoor RH band: practice criterion, referenced to DM TG 142, the practice's 60% report benchmark and the humidity provisions of ASHRAE 55-2023 / 62.1-2025 / 62.2-2025. Surface RH band: practice criterion drawn from the mold-growth literature (Johansson, Svensson and Ekstrand-Tobin, 2013); not an ASHRAE threshold. Practice criteria are labeled as such wherever they appear.
Laboratory method
Mold identified by culture in the Saniservice Department of Microbiology: settled dust sampled surface by surface, species identified under the microscope, viable counts and water-damage indicators reported location by location. DNA indices (ERMI) arranged only where specifically required, alongside culture, never in place of it.
Every note names its technical reviewer. Corrections are applied as dated amendments and the version number on the note changes; superseded figures are not silently overwritten. Readers who find an error are asked to write to research@indoorsciences.ae.
Using this work
From understanding to measurement.
The notes and models here are published for consultants, engineers, facility teams and owners who want to understand their buildings. They are general; a building is particular. Where a reading on this page describes your own property, the next step is measurement, not inference. Advisory sets out how the practice engages; Request an assessment to begin with the baseline.
