I have a house from the 40s with a wooden frame and exterior plaster. Cold attic with wood shavings as insulation. The roof has clay tiles. It's warm inside now when the sun is shining (not so unusual) but even in the evening when it gets really cool and nice outside, the warmth is retained indoors for a very long time. Last fall, it could be around 30 degrees inside at 11 PM even though it had dropped to 20-22 degrees outside.
It helps very little to ventilate, I often have the patio door and a window wide open all evening. So it's stored heat in the walls, roof, or elsewhere that emits heat long after the sun has gone down.
Can someone explain to me what is storing the heat and if there's something smart I can do to mitigate the effect?
I know the attic is very warm, even in the evening, so it's a suspect. Would it help if I ventilated it properly in the evening? The attic is not sealed at all, there are large gaps in the eaves that allow fresh air in. So it wouldn't be a problem to install a fan that pushes out hot air, but I also don't know what I would then bring in from outside in larger quantities than normal...
Grateful for tips.
It helps very little to ventilate, I often have the patio door and a window wide open all evening. So it's stored heat in the walls, roof, or elsewhere that emits heat long after the sun has gone down.
Can someone explain to me what is storing the heat and if there's something smart I can do to mitigate the effect?
I know the attic is very warm, even in the evening, so it's a suspect. Would it help if I ventilated it properly in the evening? The attic is not sealed at all, there are large gaps in the eaves that allow fresh air in. So it wouldn't be a problem to install a fan that pushes out hot air, but I also don't know what I would then bring in from outside in larger quantities than normal...
Grateful for tips.
Old houses, as you write, are often more massive and have higher thermal inertia. But if you cool them down at night, it also takes longer to warm up.
The sawdust retains heat well...
(And everything else in the construction. A lot of mass = thermally slow house)
To keep the *house* cool, you must ensure it doesn't heat up in the first place.
Ventilating the attic will work from that perspective as long as it doesn't get too hot outside.
*But* that would mean you're forcing large amounts of warm, humid air over cooler sawdust...
It's not a question of if, but when you will have issues.
The most reasonable solution is probably to invest in AC for the rooms you really want to keep cool.
If you keep those rooms reasonably cooled during the day, the nights should be bearable.
(And everything else in the construction. A lot of mass = thermally slow house)
To keep the *house* cool, you must ensure it doesn't heat up in the first place.
Ventilating the attic will work from that perspective as long as it doesn't get too hot outside.
*But* that would mean you're forcing large amounts of warm, humid air over cooler sawdust...
It's not a question of if, but when you will have issues.
The most reasonable solution is probably to invest in AC for the rooms you really want to keep cool.
If you keep those rooms reasonably cooled during the day, the nights should be bearable.
Right now it is 26 degrees indoors, I have had 3 windows wide open for some time and the outdoor air is about 20 degrees.
It's a bit bothersome...
I have postponed plans for LLVP and FTX since there are a few other structural things I wanted to change first. So right now I only have a portable AC unit and some fans available. But I will try to cool the rooms as much as possible during the evening so maybe the night will be bearable.
It's a bit bothersome...
I have postponed plans for LLVP and FTX since there are a few other structural things I wanted to change first. So right now I only have a portable AC unit and some fans available. But I will try to cool the rooms as much as possible during the evening so maybe the night will be bearable.
To measure is to know. Buy a cheap thermometer with a wireless outdoor unit and place it in the attic. Then you can easily measure the temperature there when you suspect the attic is warming up the rest of the house. Wood shavings or other wood materials don't have significant heat storage capacity, so they're not ideal. Try to shade the windows during the day. All dark surfaces indoors absorb heat from sunlight. Cover with white sheets.
I have been considering getting some wireless, or even connected thermometers that can report in and build some statistics. Maybe it's time now. Thanks for the good tips.T Thomas_Blekinge said:
By the way, I have dark brown wooden floors throughout the floor... so yes, they do absorb a good amount of heat from the sunlight.
Know-It-All
· Västra Götaland
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A plastered facade gets warm in the sun, and since your house seems quite thinly insulated, the heat comes in. In a well-insulated house, not much heat comes through the walls and roof, but mostly through solar radiation on the windows.
The air in an average house weighs about 300kg, and the rest of the house should weigh at least 100-500 times more depending on the construction. This means that airing out takes an eternity if you want to lower the temperature. The most important thing is that the house itself must never get warm. The critical step in ensuring this is to make sure the sun never shines into the house.
The surface temperature in direct sunlight can be up to 60 degrees or more when it blazes. Therefore, you must lower awnings and blinds, and close curtains. Otherwise, the heat will build up and be stored in all parts of the house. The absolute best is to have an awning that keeps all the heat outside the house, but if that is not available, blinds and curtains work well too.
The surface temperature in direct sunlight can be up to 60 degrees or more when it blazes. Therefore, you must lower awnings and blinds, and close curtains. Otherwise, the heat will build up and be stored in all parts of the house. The absolute best is to have an awning that keeps all the heat outside the house, but if that is not available, blinds and curtains work well too.
Hmm, good things to consider. It's warmest in three different rooms,Janus82 said:
Bedroom 1: Large windows with blinds
Bedroom 2: One window with a white roller blind
Living room: 1 large window with an outdoor awning, a patio door (half) and a window without any sun protection.
Anyone have tips on wireless/connected thermometers where I can save data over time? I have googled a bit and the ones I've found with that capability cost around 700 SEK per sensor and it adds up a bit since I would like to measure at least 2 rooms, attic, outdoors, and maybe basement or crawl space too. It's hard to know if they are good too, I'd gladly take tips from someone who has tested and is satisfied with a certain brand.
I understand what you're saying but isn't it the opposite now during the summer. It's warm air heated by solar radiation on the roof and the sawdust is cooler and is heated by the warm air. It easily gets over 50 degrees up there.Dowser4711 said:
Then if you ventilate, you bring in cooler air from outside (20-25 degrees) which should be quite dry unless it's raining?
Or am I thinking wrong?
There might be other things coming along with the air too, pollen, pollutants, and various spores.
A house cannot store too much energy. It's just about working with the house. A sluggish house can be kept cool relatively easily by controlling when you ventilate.