Bs 5250

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Modern construction practice aims to achieve much higher levels of airtightness. Learn more about the cookies we use and how to change your settings. Again there may be more recent versions of the document. Examines the causes and effects of condensation both surface and interstitial in buildings. The standard is relevant to buildings of all types, whatever their form, construction or level or type of occupancy, except buildings used for storage at sub-zero temperatures.

Internally, moisture is generated by building occupants and their activities. The revised guidance in G. Why does condensation occur? The idea is to prevent the leakage of warm air through the building fabric, and instead refresh the air supply by controlled ventilation.

For this reason, the airtight layer is often also vapour tight, again with the aim of using ventilation to control the movement of moisture in the building. Find Similar Items This product falls into the following categories. Methods of calculation are also given to help assess and quantify risk. Accept and continue Learn more about the cookies we use and how to change your settings. Moisture can be generated internally by building occupants, or enter the building from external sources.

Bs 5250

Collaborate, Innovate, Accelerate. Abstract This British Standard code of practice describes the causes and effects of surface and interstitial condensation in buildings and gives recommendations for their control. The question then is how to specify the roof to deal with that. Due to the natural movement of air within a building, some moisture vapour is likely to reach the roof space - especially where insulation is laid along the horizontal ceiling.

Concerns have also grown over moisture problems, generally due to climate change, as well as the drive to add insulation to walls, which disturbs the equilibrium of structures. It also specifies minimum levels of roof space ventilation. This British Standard code of practice describes the causes and effects of surface and interstitial condensation in buildings and gives recommendations for their control. Overview Product Details What is this standard about? Want access to British Standards?

Bs 5250

Although the internal air was constantly refreshed, the downside of uncontrolled ventilation was to make it harder to heat the building and keep it warm. It can also be present within the construction if the building has not been allowed to dry sufficiently.

Code of practice for control of condensation in buildings

The principles of control and the recommendations given can be applied generally to both new and existing buildings. Nearly all construction materials also allow moisture vapour to diffuse through them, to differing extents.

Bs 5250

BS 5250 2002

However, it is now agreed that, in many cases, this may cause more harm than good. Worldwide Standards We can source any standard from anywhere in the world. Recommendations for the control of surface and interstitial condensation in both new and existing buildings. The amendment to this standard follows rapid developments since in awareness and knowledge of the problems that moisture causes in buildings.

BS 5250 2011 A1 2016

The extent to which the ceiling below is made airtight, and therefore how much moisture can reach the roof space, should also influence the choice of underlay and the provision of ventilation. If the air cooled to the extent that it can no longer hold all of the moisture vapour it carried, newhouse dt font that moisture is deposited as condensation. What are the sources of moisture? How is moisture controlled?