Ceiling exhaust fans

[Viking]

Do any of you have these in your houses or apartments?

I understand they are often installed in bathrooms to reduce the humidity, but I am also curious to find out if they are effective in reducing the temperature in other rooms? Since hot air rises, it sounds like a good idea with a ceiling exhaust fan to vent it out.

What are your experiences about this? Any input is appreciated 

[Old55]

Our home in US has roof vents and an automatic thermostat controlled attic fan. This reduces the temperature of our house significantly during the short summer months here.

I know of attic fan/roof vent fans that are photocell powered. Those could be a good choice for Philippines.

[Dave Hounddriver]

1 hour ago, Viking said:

I am also curious to find out if they are effective in reducing the temperature in other rooms? Since hot air rises, it sounds like a good idea with a ceiling exhaust fan to vent it out.

I have not tried it or seen it done but the idea has merit. I have seen many native Philippine houses with a space between the walls and the roof.  I often thought it was strange they would leave a gap for lizards, rats and bugs to get in.  However, in light of what you just wrote, it is likely how they let the hot air rise and get out.  Thus it probably works.

[Joey G]

They work great... if you get one big enough (like 3000-4500 cfm), it can change the temp inside in a few minutes. Works best if you can close windows and doors and suck all the air out through one window or door.  But again it needs to be big... the small ones do little.

[Mike J]

5 hours ago, Old55 said:

Our home in US has roof vents and an automatic thermostat controlled attic fan. This reduces the temperature of our house significantly during the short summer months here.

I used to live in Washington state and am familiar with the weather there.  When Old55 says "short summer months" he is stretching the truth quite a bit.  Last year in Seattle summer happened to fall on a Thursday and the people who had to work were really pissed.  

[Mike J]

4 hours ago, Dave Hounddriver said:

I often thought it was strange they would leave a gap for lizards, rats and bugs to get in.

Lizards eat the bugs, rats eat the lizards, snakes eat the rats, so it all works out. 

[BrettGC]

We're in the process of sourcing "whirlybird" or similar roof vents for our place.  Very common in Australia, not so much in PI particularly during lockdown.  They're not powered but rather the rising hot air in the roof cavity causes them to spin drawing the hot air out.  They're most effective if there's vents in the ceiling and under the eaves.  

I installed some in my place on the Gold Coast in Australia, the difference in the ambient temperature was immediate during the summer.  

 

[manofthecoldland]

 

6 hours ago, Viking said:

Do any of you have these in your houses or apartments?

I understand they are often installed in bathrooms to reduce the humidity, but I am also curious to find out if they are effective in reducing the temperature in other rooms? Since hot air rises, it sounds like a good idea with a ceiling exhaust fan to vent it out.

What are your experiences about this? Any input is appreciated 

Re bathroom vent fans.....    I don't believe I've ever seen them used in any of half dozen apartments and houses I lived in before we built our place. The ones I come across in restos are usually kept off or are broken. 

People here rely on small jalousie slatted/louvered bathroom windows for CR ventilation when near an outside wall. Despite the outside air having a high humidity content to  begin with, the water on tiles still evaporates quickly as long as there is some natural air flow.  In temperate and cold climates you get humidity build up in enclosed bathrooms with potential mold and mildew growth, but not so much here. Here, my wife clorox saturates and scrubs our 2 tiled CRs every few weeks to prevent that, as well as to clean and sanitize.

Since many people prefer some natural light in the CR that a  small window can provide, It usually serves to both ventilate air and provide light..... all without electrical cost. Bathroom doors are often slatted near the bottom section for natural ventilation flow and many door threshold are considerably gapped also.

But if you have an interior bathroom, and don't mind the small costs and fan maintenance involved, it would be worth it I would think. But then you'd have to consider where the educted airflow is going. 

Things are usually kept as simple and low cost as possible here in most cases. No tech/Low tech is preferred or the only affordable option for many. But if you have enough money to try out other options, you are welcome to try. Passive systems are preferred due to electrical brownouts, corrosion, difficulty with part replacement and skilled  workmen.

[GeoffH]

6 minutes ago, BrettGC said:

We're in the process of sourcing "whirlybird" or similar roof vents for our place.  Very common in Australia, not so much in PI particularly during lockdown. 

I agree those work well, I haven't seen them in the Philippines though.

Be careful that the ones you get are well made, we put them on the work shed a bit before I retired and one of them developed a really really annoying squeek as it rotated and we had to get a plumber to fix it.

[BrettGC]

2 minutes ago, GeoffH said:

I agree those work well, I haven't seen them in the Philippines though.

Be careful that the ones you get are well made, we put them on the work shed a bit before I retired and one of them developed a really really annoying squeek as it rotated and we had to get a plumber to fix it.

Had the same issue with one of my as well mate, one of the bearings was buggered, like you, easily fixed by the guy who installed it under warranty.