Why it matters

• Spring Lake Park's built out post war housing stock, combined with mature tree canopy across the city, is one of the more ice dam prone combinations in the metro, since both age and shade independently extend the freeze and thaw cycle that forms a dam.

• Poor attic insulation that lets heat escape and warms the roof deck from underneath.

• Inadequate attic ventilation that keeps the underside of the roof warmer than the outside air.

• Air leaks around recessed lights, attic hatches, vents, and chimneys that let warm household air reach the attic.

• Heavy snowfall followed by freeze thaw cycles which are common through a Minnesota winter.

• Roof design and older or worn roofing materials that let water back up under the shingles once ice has formed.

When it makes sense to act

• Early in the season for Spring Lake Park's older ramblers. With little new construction in the city, most homes here carry the same aging attic risk, meaning ice dams tend to appear sooner than in newer suburbs.

• Before repeated freeze thaw cycles compound an existing dam. Older attic systems in a built out suburb like this rarely resolve an ice dam on their own between cold snaps.