In respiratory physiology, ventilation is the exchange of air between the environment and the lungs by means of inhalation and exhalation. So, for organisms with lungs, it is what is popularly known as respiration. Ventilation usually occurs in a rhythmic pattern, and the frequency of this pattern is called ventilation rate (or, by a de facto convention, respiratory rate, although in a precise sense, ventilation is actually a hyponym, not a synonym, for respiration).
Pulmonary ventilation can be assessed using a breathing tube or spirometer, by measuring the movement of the chest and abdominal walls using respiratory inductance plethysmography, or by isolating the subject in a closed metabolic chamber (body plethysmography).
Attic is a polysemous term that designates both the space under the roof itself (formerly attics, lofts, attics, attics and today almost always living spaces) and now the windows that illuminate and ventilate them. In other languages different words are used (in fr., comble/lucarne; in it., soffito/abbaino; in en., attic/dormer …), being this the cause of problems derived from borrowings and translations. The confusion extends to the same use of attic/buhardilla/attic, lumbrera/lucera/lucernario/claraboya/lucernario/tragaluz or even the recent roof windows or velux (trademark). From the import of the French lucarne, lucarnas or lumbreras were formerly used, now with different meanings and in disuse.
The dormers can have numerous forms, dimensions and dispositions, and have one or several windows and be developed on one or several levels. They can also be the crowning element of a building.
Natural ventilation in houses
Gable vents are installed at the gable ends at opposite ends of the attic. They are most effective when the wind is aligned with the prevailing winds. When the prevailing winds blow perpendicular to the wind, the gable vents act as both intake and exhaust.
Insufficient ventilation can cause moisture problems during the winter and decreased energy efficiency during the summer, but too much ventilation can be just as bad, if not worse.
Do gable vents leak? Virtually all wind gable ends (Figure 9) will leak when wall mounted in wind-driven rain faces. If installing shutters from the outside is difficult due to height or other considerations, but there is access through the attic, the gable vent opening can be closed from the inside.
Gable vents are installed at the gable ends at opposite ends of the attic. When prevailing winds blow perpendicular to the wind, the gable vents act as both intake and exhaust. Less air exchange occurs and attic ventilation is not uniform, making it less effective.
Should I use a ridge/soffit vent or an attic fan?BWDesignI’m getting ready to redo the roof on our house (shingles and some siding) and am wondering what type of vent I should add to the roof. The roof currently has no ventilation at all and as a result, there is mold and mildew and the siding is rotting and sagging.
DMooreBefore I added my ridge vent when we had consecutive 100F days, the attic could get to 120-125 easily, and my roof is very shady. It would come down completely soaked – like a soggy swimming pool – when I was doing 15 minutes of electrical work.
I just added a ridge vent to my attic a few months ago. Attic temp measured after a couple of days in the 90s and the high temp went from around 7pm to the low 90s, but basically stayed in the mid 80s. Then temperature change of 25F, being conservative.
Not sure what an attic fan would do in comparison. The air needs to get out of the attic. The warm air will escape upward. The attic fan will pull the hot air out of your house and into the attic, with nowhere to go. I could almost see the attic fan barely making a difference because of the heat introduced by the component in this situation. And from an energy standpoint, it doesn’t make sense to run something that makes low differences. In this situation, I could see that using their AC is more efficient.