In the winter, household activities, such as cooking, showering and doing the laundry, generate moisture that can damage the attic insulation and building materials of the roof. In the summer, attic temperatures can rise to over 150° F., which can cause premature aging and cracking of wood and roofing materials. These elevated temperatures can also increase cooling costs for the home owner. In the construction of rooves, therefore, it is often desirable to provide a ventilation opening at the roof ridge and cover it with a vent. Ridge vents are passive ventilation systems which provide openings through which air can convectively flow to and from under the roof structure to provide ventilation.
Ridge vents typically cover any elongated opening, such as one that is formed in a roof andNew Delhi: A 25-year-old youth tried to set himself ablaze outside Home Minister Rajnath Singh's residence at Ashoka Road here on Friday evening in the heart of the national capital.

According to police, the incident took place around 5:15 pm when the youth, who was later identified as Dabbu poured kerosene and tried to self-immolate near the railing.

"Security personnel deployed at Home Minister's residence quickly overpowered him before he could set himself afire. He was taken to RML hospital in a semi-conscious state. We are waiting for him to come to senses so that we can record his statement and know the reason behind his step," said a senior police official.

There were cut marks on his hands and we have asked doctors to see whether he was under the