​Heat Recovery Ventilation

​Buildings have now improved with insulation and weatherstripping, they are intentionally made more airtight, consequently made less ventilated.

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Buildings all require a source of fresh air, and the need for heat recovery ventilation has become very obvious. While opening windows does provide a good source of ventilation, heat and humidity within the building will then be lost in the winter and gained in the summer, both of which are undesirable for the indoor climate and for energy efficiency.​