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Construction

Measurement of air tightness (blower door test) together with infrared thermography is an easy-to-do test to check the thermal quality of the building envelope.
Prefabricated wet room module contains all the necessary heating and ventilation equipment installations. The ductwork needs only to be plugged at the site.

Heat losses
The most important phases of the construction are insulation installation and building the air tightness for the house. Insulation materials should be chosen and installed adequately according the structure. Thermal insulation must fill a cavity completely, or lay tight against supporting or load-bearing structures. There should not be any air voids or cavities in the insulation layer. The insulation work itself should be made possible to carry out without much cutting insulation boards or cutting air barriers, e.g. when installing loose fill insulations by blowing. This requires right dimensions for insulation material and load-bearing structures. Here also modular dimensions and prefabrication of wall systems are beneficial.

Window to wall and door to wall connections are often a source for air leakages. Basically the same requirement for sealing applies to all materials and building systems. Simple but efficient sealing techniques do exist, but often also climate affect on the result. Typically dry and clean surfaces and above 0oC temperatures are required. Crimped joint between air barrier (vapor barrier or building paper) and frame structure is not adequate, but the connection needs to be sealed as well. There has been a lot of discussion on the long-term durability and stability of different adhesives used for sealing. One should always choose products that have either tested or adequate reference data on their performance.

Installations
Ventilation ductwork should locate inside the air barrier. Only fresh air and exhaust air ducts penetrates the air barrier layer. The installation details need to be sealed. There are flanges of different sizes that allow for easy and airtight solutions. Direct routes for ventilation ducts are beneficial. If the design layout has defects, the problem should be solved together with the HVAC designer and architect. Careful installation and insulation of the ductwork, e.g., in unheated or cool rooms serves for efficiency and noiseless air supply.

The ductwork of a ventilation heating system needs to be insulated to avoid heat losses from the system. Boilers and hot water system should locate in areas where their heat loss can be utilized. A technical room in the centre of the building is the most advantageous solution. This is also a good starting point for spatial planning of the house.

Water pipe work should be a surface installation or casing pipe installation if embedded into structures to avoid moisture risks. Hot water pipes need to be insulated. In typical apartment buildings with un-insulated hot water pipes, nearly 20% of all heating energy may come from heat losses in hot water system.

Commissioning serves for desired quality. Testing includes required ventilation rates, air tightness, and search for possible air leakages by thermographic camera in winter or smoke tests in summer.