Information on BS5250: Moisture in Buildings

Information on BS5250: Moisture in Buildings
ukcmb_zrundz

This standard will be much more comprehensive than the previous standard which was concerned primarily with condensation in buildings. The new standard will to some extent follow the BSI White Paper on Moisture in Buildings and deal not only with surface and interstitial condensation but also with other moisture mechanisms, in particular rain penetration and ground water issues. It will also cover the connective and systemic effects (i.e. junctions, interfaces and whole building effects) of moisture and the As Built, In Service (ABIS) conditions of buildings, since most moisture risk occurs at junctions and from building errors and degradation in real world situations. All this will be considered with regard to both fabric moisture and atmospheric moisture, which respectively affect the durability of the physical building and the health of building occupants.

Work on this new standard is progressing slowly but surely. There has been useful work undertaken on the whole structure of the document and on the particular elements of buildings. The elemental approach (divided into categories, as previously, of floors, walls and roofs) is being retained but integrated with this new holistic approach. This is necessary as designers and contractors necessarily work from building elements when it comes to practical detail. The questions that are being raised in the committee largely revolve around how assessment and risk management can be made simple enough to be practical, but not so simple as to create further problems and unintended consequences. There is also an important question of how the standard can be applied by regulators and compliance bodies.

It is hoped that the work will be completed in 2019. It is important that it is aligned with work in other areas such as Each Home Counts, PAS 2030 and PAS 2035. It will also be necessary for training and professional qualifications to be developed for its implementation to ensure it makes buildings and building processes more robust, not more complicated.