Ice dam repair in Des Moines

Why Des Moines roofs get ice dams

An ice dam forms when the upper roof is warm enough to melt snow and the eave is cold enough to refreeze it. The melt runs down under the snowpack, hits the overhang — which has no warm house under it — and freezes into a ridge. The next melt pools behind the ridge, and because shingles are designed to shed water running downhill, not sitting in a pool, it backs up under them and into the wall.

Des Moines gets about 35 inches of snow a year and spends most of December through February crossing 32°F every few days. That's the recipe. The houses that get it worst are the city's 1920s–50s stock — Beaverdale, Drake, Highland Park, the Waveland Park bungalows — with low-pitched roofs, tiny attics, no soffit vents, recessed lights and bath fans dumping warm air straight into the rafters. But a 2010 Johnston two-story with a cathedral ceiling over the great room and a bath fan that vents into the attic will do it just as well.

Ice dam removal

Ice dam roof repair in Des Moines starts with getting the dam off without wrecking the shingles.

Steam. The right tool is a low-pressure steamer that cuts channels through the ice and melts the dam off the roof. It's the only method that doesn't damage shingles. $400–$1,000 for most eaves, depending on how much ice there is and how many roof edges are involved.

What nobody should do. No hammers, no ice picks, no hot-water pressure washers, no rock salt in a stocking. Every one of those tears granules off or splits shingles, and you'll pay for a new roof edge in April.

Roof raking — pulling the snow off the bottom four feet of the roof from the ground — is what you do between storms to keep the dam from forming. A $40 roof rake at the hardware store is the cheapest roofing tool in Iowa.

The day you spot an ice dam

1. Look inside first. Check the ceiling and walls along the outside wall under the dam, and the attic above it if you can reach it. Put towels and a bucket down.
2. Rake the lower roof from the ground so no more snow melts into the pool behind the ice.
3. Clear the downspout outlet. If the downspout is frozen solid, the gutter has nowhere to drain. Don't chop at the gutter itself.
4. Photograph the ice, the icicles and every stain, with the date.
5. Call for steam if water is coming in, or if the ridge of ice is more than a few inches thick.

Calcium chloride in a stocking laid across the dam is a common trick. It can cut a drainage channel, but it can also stain siding and burn the plants under the eave, so treat it as a stopgap at best. Never use rock salt, which eats at shingles and gutters.

Questions to ask before ice dam removal

• Do you use low-pressure steam? Anything else should be a no.
• Is the price by the hour or by the job, and what does it include?
• Will you clear the gutters and downspouts too?
• Will you photograph the roof edge once the ice is off, so I can see whether shingles or flashing were damaged?
• Can you look in the attic and tell me where the warm air is getting in?

The last answer matters most. Steam fixes this winter. The attic fixes every winter after.

Ask for the price in writing before the steamer comes off the truck. After a big snow and a sudden thaw, calendars fill within a day or two, and a clear quote saves an argument about hours later. If the contractor finds damaged shingles or soft decking once the ice is gone, that repair should be a separate written price, not something added to the bill on the spot.

Repairing what the dam did

Once the ice is gone, look at what it damaged. The usual list, and typical prices:

• Water-stained or lifted shingles on the first three or four courses: $300–$800 to re-lay with ice-and-water membrane underneath
• Rotted fascia and the first sheet of decking behind a gutter that has iced up every winter: $500–$1,500
• Gutters pulled loose or bent by the ice load: re-hang or replace the run
• Interior drywall, insulation and paint — photograph it for the insurer; ice dam water damage is usually a covered loss, though the cause isn't

If the roof is due anyway, this is the moment to plan a replacement with membrane run two full courses up the eave, which Iowa code requires and which most 1990s roofs don't have.

Stopping it: the attic is the fix

A roof leak from an ice dam is a symptom. The disease is warm air getting into the attic. Every ice dam job should end with an attic inspection, because the prevention work costs less than the second steam call.

1. Air-seal the attic floor. Foam around every wire and pipe penetration, caulk the top plates, gasket the attic hatch, box recessed lights with fire-rated covers. This is the single most effective thing, and the most skipped.
2. Vent the bath fans and dryer outside. Through the roof or the gable, never into the attic. A family of four puts gallons of warm, wet air into the attic every day through a fan that stops at the insulation.
3. Bring insulation up to R-49. Central Iowa is climate zone 5; most 1950s attics have a third of that. Check MidAmerican Energy's current rebate list before you buy.
4. Balance the ventilation. Soffit intake and ridge exhaust, with baffles so the insulation doesn't block the soffits. Roof ventilation in Des Moines is neglected on old houses because the soffits are narrow; there are low-profile solutions.
5. Heat cables as a last resort for a specific problem eave — a north-facing valley or a low-pitched porch roof — not as the whole plan. They cost money to run and hide the underlying issue.

Our seasonal guide on ice dams and how to stop them covers what you can do yourself before the first snow. If the leak is showing up without any ice at all, it may be condensation, not a leak.