ᐅ Is Using a Construction Dryer Useful After Handover, or Is Window Ventilation Enough?
Created on: 1 Dec 2017 14:33
S
sauerpeter
Hello everyone,
We are considering investing some money in purchasing a construction dryer. For us, the building handover is already complete. The person who conducted the blower door test mentioned that there is still a lot of moisture in the house. You can also notice it when entering the house or ventilating thoroughly.
We are wondering if a construction dryer is still useful when the painting work is already fully finished? Or is it counterproductive because the paint might lose moisture or something like that?
Or is ventilation alone enough? Regarding ventilation, we take turns with my parents-in-law since we basically travel between three locations. One day I go early before work and ventilate all open windows for 15 minutes. Then in the evening, the same again for 15 minutes. The next day, my parents-in-law ventilate once for 15 minutes. The following day, I do it again, and so on. On weekends, we ventilate more frequently when we are there, about 3 to 4 times.
Or does a combination of both bring the best results?
Thank you very much for your help.
We are considering investing some money in purchasing a construction dryer. For us, the building handover is already complete. The person who conducted the blower door test mentioned that there is still a lot of moisture in the house. You can also notice it when entering the house or ventilating thoroughly.
We are wondering if a construction dryer is still useful when the painting work is already fully finished? Or is it counterproductive because the paint might lose moisture or something like that?
Or is ventilation alone enough? Regarding ventilation, we take turns with my parents-in-law since we basically travel between three locations. One day I go early before work and ventilate all open windows for 15 minutes. Then in the evening, the same again for 15 minutes. The next day, my parents-in-law ventilate once for 15 minutes. The following day, I do it again, and so on. On weekends, we ventilate more frequently when we are there, about 3 to 4 times.
Or does a combination of both bring the best results?
Thank you very much for your help.
R
readytorumble4 Dec 2017 11:28I assume you decided not to install a mechanical ventilation with heat recovery system? That’s unfortunate—I hope you won’t regret it.
We had to turn off our mechanical ventilation yesterday because during cold nights, condensation forms directly on the fresh air intake grille on the facade, damaging the new exterior. It’s frustrating, and after less than 24 hours without ventilation, it’s already noticeable.
But back to the topic: The units you can buy for around 350€ (about $375) are not worth it. We had one borrowed from a family member, and it extracted about 5 liters (1.3 gallons) of water from the building in 24 hours. Considering the electricity consumption, it would have been better to skip it altogether.
We had to turn off our mechanical ventilation yesterday because during cold nights, condensation forms directly on the fresh air intake grille on the facade, damaging the new exterior. It’s frustrating, and after less than 24 hours without ventilation, it’s already noticeable.
But back to the topic: The units you can buy for around 350€ (about $375) are not worth it. We had one borrowed from a family member, and it extracted about 5 liters (1.3 gallons) of water from the building in 24 hours. Considering the electricity consumption, it would have been better to skip it altogether.
S
sauerpeter4 Dec 2017 11:37readytorumble schrieb:
I assume you decided against installing a mechanical ventilation with heat recovery system? That’s a pity—I hope you won’t regret it.
We had to turn off our mechanical ventilation system yesterday because it was causing condensation at the fresh air inlet directly on the façade on cold nights, which damages the new exterior. It’s frustrating, and after less than 24 hours without any ventilation, it’s already noticeable.
But back to the point: the units you can buy for around €350 (about $370) are not worth it. We also borrowed one from family, and it extracted about 5 liters (about 1.3 gallons) of water from the building in 24 hours. Considering the power consumption, it wasn’t really worth it. No, we don’t have mechanical ventilation with heat recovery.
Well, the issue with the dehumidifier and 5 liters (about 1.3 gallons) in 24 hours needs to be seen objectively. Usually, those 5 liters go into the collection container, and when it’s full, the device switches off. You either have to empty it or attach a hose to channel the water into a larger container, which then allows the device to run longer and extract more moisture.
The devices we are looking at are supposed to remove about 55 liters (about 14.5 gallons) from the building. Of course, that’s not exact, even if it’s only 40 liters (about 10.5 gallons). Calculated over 2-3 weeks, that adds up.
Aside from the electricity consumption, which is the other side of the coin, it’s still better than risking mold—because the costs later would be higher, not to mention the health risks… especially since we have a young child.
sauerpeter schrieb:
But the guy from the blower door test still said there was a lot of moisture inside.Yes, but that generally applies to any solid construction—it was just mentioned by that person.
Still, there are certain rules for drying. You can’t just start drying right away; for example, you need to let it rest for 48 hours and then begin slowly. After the screed, the procedure was: start ventilating after 48 hours, and only use a construction dehumidifier after two weeks.
About the construction dehumidifier: I don’t know what you had. Ours was running, removing about 80 liters per day. You can’t get one like that for just a few hundred euros, and we were able to pick it up ourselves. It fit in the trunk of a car 😉
After one or two weeks, such a device is no longer worth it... but the moisture will still be inside your building even after a year.
Regarding the floor: a professional measures to determine if it’s ready for covering.
K
Knallkörper4 Dec 2017 11:49You are approaching this the wrong way. First, invest in some reliable hygrometers (starting at 12 euros), and place them throughout the house. Then you will have accurate readings to base your decisions on.
We don’t have a mechanical ventilation system, but we use trickle vents and our roof windows are always set to the ventilation position. We constantly feel like there is fresh air inside the house. Before moving in at the end of April, we dried the house using a construction dryer until the indoor humidity was below 30% RH. This process took several weeks. Now in winter, we are happy if the humidity doesn’t drop below 40%. Therefore, I would no longer agree with the common statement that a house always struggles with moisture during the first year.
Before installing the floor covering, the residual moisture in the screed should be measured.
We don’t have a mechanical ventilation system, but we use trickle vents and our roof windows are always set to the ventilation position. We constantly feel like there is fresh air inside the house. Before moving in at the end of April, we dried the house using a construction dryer until the indoor humidity was below 30% RH. This process took several weeks. Now in winter, we are happy if the humidity doesn’t drop below 40%. Therefore, I would no longer agree with the common statement that a house always struggles with moisture during the first year.
Before installing the floor covering, the residual moisture in the screed should be measured.
sauerpeter schrieb:
but still better than risking mold... the costs later on are higher, not to mention the health issues... and we have a small childAgain: You cannot remove all moisture just by intensive drying now; long-term ventilation, heating, and so on are necessary.
The moisture that causes mold is generated when people live in the house, sweat out several liters overnight (each adult up to one liter), cook, shower, heat, and do not ventilate.
R
readytorumble4 Dec 2017 11:59sauerpeter schrieb:
No, we don’t have a controlled residential ventilation system.
Well, the issue with the dryer and 5 liters in 24 hours needs to be considered objectively. Sure, usually only about 5 liters fit in the collection container. When it’s full, the device switches off. You have to empty it or connect a hose that leads the water to a larger container, which then allows the device to run longer and extract more moisture.I looked into it. The device we had cost 320 € and is rated for 52 liters per 24 hours.
In our case, it wasn’t because we didn’t empty the container. The cheap model only managed to extract 5 to 10 liters.
Decent construction dryers cost four figures.
Similar topics