Stop heating the heated basement?

Hello everyone,

I have bought an old building from 1970 and will be moving in soon. The house is fully basemented and there is also a laundry room there. The masonry of the basement is described as: "KSV 1.8/150, d=36.5cm, with insulation coating on the outside in the ground." Furthermore, there are many windows, some of them only with a protective grille. The basement itself is separated by a door, so it is not "open."

The basement is also fully heated, so many radiators are present, etc. The heating was usually set to 2-3 in the basement by the current owner, and it was warm in winter when you were down there.

But now, of course, we hardly/nearly never go down to the basement and definitely do not need 20 degrees there, and we also want to replace all the windows with double-glazed windows since these old grilles are not really helpful.

What dangers can arise from turning off the heating or setting it to a maximum of 16 degrees? Can mold develop this way? What do you think? It’s about saving energy; heating the basement continuously is just too expensive.

The answer depends entirely on how damp the basement is. The house is 50 years old. Back then, basements were not made completely watertight. Is there stagnant moisture, a high groundwater level, or layer water? Because the windows have so far only been partially barred, there has always been good air exchange, which you would block with new windows. I would do the following: install new windows, turn off the heating, and measure the moisture, both in the air and in the walls. As long as everything stays within limits, you can keep the plan.

For a "normal" basement from this construction year, I would leave the windows as they are. Unlike the house, the basement can actually breathe. The money saved then goes into insulation on the basement ceiling. You really notice that in winter, how warm the floor gets - otherwise, cold feet take on a very intense meaning. But it makes the basement a few degrees cooler, and you have to heat significantly less upstairs.

With a "normal" basement from this construction year, I would leave the windows as they are. Unlike the house, the basement can actually breathe. The money saved can then be spent on insulating the basement ceiling. You'll really notice in winter how warm the floor becomes – otherwise, cold feet take on a very intense meaning. It does make the basement a few degrees cooler, and you'll have to heat significantly less upstairs.

Could I also install new windows and then additionally insulate the basement ceiling? And then occasionally ventilate in winter and keep it closed in summer? Or do the old windows absolutely have to stay in?

There is also a laundry room in the basement; could there theoretically be problems there? Or could I just leave the window open while the laundry is drying?

Or would window rebate vents possibly help here along with an exhaust fan? The basement is anyway not inhabited and it is in a quiet area.

Could I also install new windows and then additionally insulate the cellar ceiling? And then occasionally ventilate in winter and keep it closed in summer? Or do the old windows necessarily have to stay in?

That depends on how dry or damp the cellar actually gets. Occasional ventilation will not work if some moisture is always coming into the cellar. Difficult to assess from a distance.

There is also a laundry room in the cellar, could there theoretically be problems there? Or could I just leave the window open while the laundry is drying?

Theoretically yes, it's a ventilation issue ==> see above.

Or would window rebate ventilators possibly help here along with an exhaust fan?

Probably (gut feeling) a properly sized window rebate ventilator alone is sufficient so that you have continuous ventilation. Almost like now, but with new windows.

Or would window rebate ventilations possibly help here with an exhaust fan?

Just an idea, no idea if it makes sense: install windows (with or without window rebate ventilation) and remove part of the rubber seal. Then, at least that's how I imagine it, air exchange would occur more easily. But maybe that's very bad and I just don't know it. I thought about this for our residential house because our house builder doesn't install windows with window rebate ventilation and we didn't want to install a ventilation system.