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.
Part IResearch Notes
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.

Research Note 01v1.1 · September 2026

The Control Volume

Why cold surfaces in cooled buildings get wet. An interactive model showing how indoor humidity and surface temperature create condensation conditions, and how room pressure indicates possible moisture-transport paths, in cooled UAE buildings. Outdoor condition drawn from the Dubai International hourly record, 1983 to date.

Interactive modelDew point · surface RH · pressureTechnically reviewed
Part IIEssays
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.

In memoriam · Read the tribute on The Practice

Part IIIBasis
Technical notes and methods

The datasets, the procedures and their limits.

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 record, decimal resolution, 1983 to date; official source of record the UAE National Center of Meteorology. June–September window, n ≈ 116,000 hours: median 23.1 °C, 95th percentile 28.0 °C. Whole-year share of hours above 22 °C by station, seven stations including the inland exception. Technical note PDF to be rendered from the approved HTML
Psychrometric method
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) used alongside culture, never in place of it. How we identify mold
Review and correction
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

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.