CONDITIONS:
1.Warm air rising in the attic
2. Outside Temperature below 32
3. Heavy snow and ice accumualtion
4.Throughout winter ice and snow melts and refreezes and the water gets trapped under the roof shingles, soon cracks
form and water leaks from roof deck into interior of home
PREVENTION:
1. Insulation in attic reduces amount of hot air in attic
2. Roofing underlayment makes water tight barrier between shingles and roof deck
3. Proper ventilation vents warm air out of attic and keeps roof cold (soffitt ventilation helps as well)
4.Snow melts evenly now so it does not have a chance to build up