When does normal stack effect occur?

When does normal stack effect occur?

• A. During the Winter
• B. In the Summer
• C. Only at night
• D. During the Fall

Answer: (A)

Stack effect happens when there’s a temperature difference between inside and outside a building. Warm indoor air is less dense and rises, escaping through upper openings, while cooler outdoor air is drawn in through lower openings to replace it. The driving force is the indoor-outdoor temperature difference, so it’s strongest when outside is cold and inside is heated—typical of winter. In summer, air conditioning keeps indoor temperatures closer to outside, so the effect is much weaker and can even reverse under certain conditions. It isn’t tied to night specifically; the key factor is the temperature difference, which is most pronounced in winter.

Stack effect happens when there’s a temperature difference between inside and outside a building. Warm indoor air is less dense and rises, escaping through upper openings, while cooler outdoor air is drawn in through lower openings to replace it. The driving force is the indoor-outdoor temperature difference, so it’s strongest when outside is cold and inside is heated—typical of winter. In summer, air conditioning keeps indoor temperatures closer to outside, so the effect is much weaker and can even reverse under certain conditions. It isn’t tied to night specifically; the key factor is the temperature difference, which is most pronounced in winter.