Moisture control in construction requires seamless teamwork

20/05/2019

Moisture-related damage and indoor air problems and the financial and humanitarian costs have dominated the discussion related to construction over recent years. The reputation of the construction industry has been hit hard in the discussion. The industry has responded to the discussed problems by developing collective moisture control procedures and instructions.

The best end result is achieved when moisture control is in order during all phases of the building’s life-cycle.  This requires all players in the construction process, the entire team, to secure the dry chain.

Put simply, the construction team consists of five players – the developer, designer, material manufacturer contractor and the user. When moisture causes a problem, the blame is usually placed on the contractor. It is in fact true that the contractor often serves as a safeguard against moisture. The contractor is responsible for ensuring that the materials and structures are appropriately protected against moisture during construction. Naturally, the building and structures must also be implemented according to the plan, without errors and correctly for moisture control. 

RainTo the layman, materials and structures exposed to the weather do not look good. However, according to research, only a very small share of the moisture problems in buildings is caused by materials allowed to get wet for a short period during construction. The most significant reasons for the problems are construction and design errors, use of the building and poor maintenance. 

The problems with controlling moisture may also originate from the very early phases of the construction process; the choices and decisions made by the developer. The developer sets the moisture control goals for the project, which are implemented in the other phases of the construction project.

The designer is responsible for taking the ball from the moisture control goals set by the developer and implement them in the designs. The designer is responsible for ensuring that the planned structures and selected materials ranging from the exterior and insulation to surface materials are effective against controlling moisture. Good, clear designs make the builder’s work easier and prevent errors from being made during construction.

The contribution of material suppliers in ensuring moisture security cannot be undermined. Openly sharing information on the properties of the materials, their behaviour as a part of a structure and the correct storage procedures for the delivered products with “team mates” improves the ability to ensure good moisture control throughout the chain.  Of insulation materials, stone wool is an example of a porous material that does not accumulate moisture even in tough conditions as it allows structures with moisture to dry effectively through it. This is important to know during both the design and construction phases, as the drying times of structures are critical for the project work-flows.

The user of the building has a much greater role in preventing moisture damage than is often thought. It is important for the user to inspect the structures, wet areas and appliances and perform the necessary maintenance activities regularly. The building’s maintenance record contains the technical useful lives of the equipment and materials, which is useful for preparing for future maintenance and repair procedures. Eliminating the humidity loads in the indoor air created through living are handled using sufficiently effective ventilation, for example. 

A lot of education work regarding moisture control is surely yet to be done throughout the entire chain – but now is a good time for it, as moisture control during construction is already dominant in public dialogue.

Susanna Tykka-Vedder

Susanna Tykkä-Vedder
Application Manager, Paroc Oy