On a hill, mechanical ventilation was not the best possible.

In Vantaa, the mechanical exhaust ventilation was updated to modern heat-recovering ventilation, and the city joined the climate effort.

Jari Mäkinen and Piia Purola's home experienced ventilation problems last summer when the air stagnated even with interior doors and windows open. The rooms wouldn't stay fresh at night, which meant sleep wasn't always the best it could be. Read the article and watch the video to see how the ventilation renovation went.

How were the ventilation problems detected?

Ventilation and indoor air quality problems are usually difficult to detect in time, at least if people have been living in the house for a while. However, Piia and Jari were lucky because they had previously lived and worked in buildings with good modern ventilation. Thanks to this, they knew that a ventilation renovation in an old house could achieve significantly more comfortable air to breathe.

Poor ventilation might not be noticed if someone has lived in a house for a long time and has gotten used to the building's deficient ventilation. Good ventilation, on the other hand, can't be heard, seen, smelled, tasted, or felt. After a ventilation renovation, the air inside can be as energetic and fresh as the air outside, but warm.

What ventilation renovations had been done previously?

The building has been Jari's childhood home. It was built in the 1970s with gravity ventilation. Stone single-family homes were not common at that time, so the house was quite ahead of its time in every way. The house is a semi-detached house, with its halves built at slightly different times.

In the 2000s, a new ventilation renovation was carried out in the house, and a mechanical exhaust fan was installed in the wet rooms and the range hood. The problems with mechanical exhaust ventilation are usually high electricity or other heating energy consumption, as heated air is blown directly outside the house all winter, and replacement outdoor air enters the house through cracks in the walls or window vents. However, the outdoor air always needs to be reheated so that the house doesn't completely freeze.

In addition, houses built with mechanical ventilation are usually very negative pressure due to the supply of replacement air. Negative pressure, on the other hand, is a bad thing in old houses because it means that air has to be drawn in from somewhere, and if it is not supplied in a controlled manner through replacement air vents, it is usually drawn in through the walls. This can cause respiratory problems, as there are various kinds of germs or even asbestos between the walls that can be carried into the breathing air. Watch this guide video on how ventilation works in old houses.

How did you end up choosing Fresh for the ventilation renovation?

When asked ”how you ended up with Freshin for the ventilation renovation,” Jari said he had extensively researched the internet and explored many different options. He had found Freshin and read many discussions, comments, experiences, and technical information about Freshin's systems, after which he was convinced. He then quickly contacted Freshin through their website.

The ventilation specialist was indeed helpful and came to visit the very next day, when the free measurements were started. The measuring devices were calibrated, and reliable data was collected from the building, based on which conclusions about the best possible solution could be made more reliably.

After the measurements, Jari and Piia received the measurement results and an offer for the renovation. The offer was clear, reliable, and the order was easy to place. After this, the installations began the following week and the work was completed within the same week. Immediately after the installation, the ventilation system began saving money for the residents.

What kind of ventilation renovations were done?

During the ventilation renovation, the building's negative pressure and the functionality of the old ventilation systems were first checked, and based on this, the design of the ventilation renovation was initiated. In addition, carbon dioxide, TVOC, humidity, and air pressure values were measured in the building with precise instruments. The building's energy consumption was also investigated.

Based on measurement results and calculations, professional ventilation designers concluded together with the clients that the building should have mechanical supply air added, and by reducing the building's heating costs, the ventilation renovation could be paid back in approximately 6 years. After this, the ventilation renovation will start saving residents money.

The villa was equipped with six Fresh air room-specific heat recovery ventilation units. Due to the long, corridor-like layout, a transfer fan was also installed in the living room to distribute the heat from the fireplace more effectively to all rooms.

What difference did residents notice after the ventilation renovation?

Piia said that after the ventilation renovation, the difference was immediately noticeable. The indoor air was perceived as fresher, closer to the oxygen-rich air outdoors. Odors disappeared from the bedroom better, and warm air from the fireplace and air-source heat pump circulated better throughout the house, as a result of which living became more comfortable and wool socks were no longer needed as often.

Jari reported again that the negative pressure was gone. Previously, a negative pressure of -9 Pa was noticeable in the house just by opening the outer door, and the house's ventilation had been more dependent on the outside temperature and wind than on the ventilation performing its intended functions. Now the air quality is significantly better in all weather conditions.

The ventilation renovation installation was completed in two long days, and the Freshin ventilation installers had cleaned up their mess well, and they were not even a disturbance to Piia, who worked from home. When asked, Jari said that he had been involved in many renovations, but this Freshin ventilation renovation had gone excellently, and there was nothing to complain about.