• Ventilation duct could be either be branched or radial. A branched duct will have T-pieces at its end to allow it to branch in smaller tributaries. This is a widespread design used in most homes. You can incorporate ducts of various sizes in such a layout along with silencers. In a radial duct there are two boxes of different sizes connected back to the MVHR unit. One of them is for supplying fresh air and other for extracting stale air from rooms. A circular duct of a semi-rigid length of 75mm is extended to each room to provide adequate ventilation. .
• Avoid flexible ducts for ventilation. These increase the resistive pressure applied to your MVHR unit. It will have an adverse effect on your unit’s performance. It will increase the fan speed and noise and the heat recovery capacity will go low. .
• In modern super insulated houses, there is tendency among homeowners to fit ductless mini-split systems. These systems are energy efficient, inexpensive, and easy to install. What type of ventilation would work best for such homes as there is no duct work? The usual options that are utilized in homes are that of exhaust only ventilation or dedicated ventilation duct work. But is has often been found in such cases the remote bedrooms of the house stays several degrees cooler than the living rooms. This creates comfort problem. In such a case the duct work can be designed that would take all of the home’s fresh air to a ceiling diffuse near the ductless minisplit unit, and all of the home’s exhaust air could be extracted from the upstairs bedrooms. You can fit spot exhaust for the bathrooms and kitchens. This type of ventilation duct work would allow gentle air to flow from the warm, conditioned living room towards the remote bedrooms.