What a Michigan winter does to permanent lights

The short answer

On a real house, three places take the winter: the eave, where ice builds and sliding snow arrives; the gutter, which fills and gets heavy; and the power lead, the short run of wire from the roof edge down to the outlet. Where the channel is fastened relative to each of those decides how a permanent system comes through February.

A LightCast system is a rigid aluminum channel of RGBW diodes, mounted on the fascia board or in the lip beneath the drip edge, and never driven through the shingles. That puts it at the eave, the spot winter works hardest, so this guide spends most of its time there.

What Metro Detroit winters bring

The National Weather Service office in Detroit/Pontiac published its 1991–2020 climate normals with Detroit averaging 45.0 inches of snow a season, 2.5 inches more than the 1981–2010 normals. January averages 25.8°F.

The middle two rows matter most. A January with its average high right at freezing and its low well below is a month of daily freeze and thaw: snow softens in the afternoon, water runs down the roof, and it hardens again after dark. That cycle builds ice dams and loosens anything only clipped in place.

Ice storms are rarer but harder on a house. On February 22, 2023, much of Metro Detroit south of I-69 took a quarter to half inch of ice. The weather service's summary cites DTE reporting nearly 3,000 downed wires and close to 500,000 customers without power, and notes that for many Metro Detroit communities it was the first ice storm with this wide a footprint since April 2003.

LEDs in the cold, in one line

Cold does not hurt the diodes: an LED has no filament to break, and the Department of Energy lists good performance in cold temperatures among the traits that make LEDs useful in many lighting applications.

That is the whole temperature story. How many years of use the diodes themselves deliver is a separate question, answered in how long permanent lights last.

Ice dams and the drip edge

An ice dam is a ridge of ice along the lower edge of a roof. University of Minnesota Extension explains how one forms: the higher part of the roof surface sits above 32°F while the lower part sits below it, so snow melts up high, runs down the slope and freezes when it reaches the cold edge.

The overhang at the eave sits outside the heated house, so it is often where that cold lower edge is.

The Building America Solution Center, a Department of Energy resource, lists three ingredients: snow on the roof, an attic that leaks warm air or lacks insulation, and freezing temperatures. It notes a dam can form with as little as 2 inches of snow on the roof, and that water pooled behind the dam can be drawn up under the shingles and cause leaks.

Where that leaves the lights

The dam grows on the roof surface, on top of the shingles and behind the drip edge. A channel on the fascia face, or set into the lip below the drip edge, sits below and in front of that ridge, on vertical trim. Icicles will hang past it, and a bad week can glaze its face, but the mount is not what the ice is pushing against.

This is also the practical reason nothing goes through a shingle. A fastener in the lowest courses would sit exactly where water pools behind a dam, and every hole there is a path into the roof deck. That is why the channel goes on the trim, and our guide to where eave lights mount under the drip edge explains the fascia and drip-edge positions in more detail.

What to avoid when the eave ices up

• Hammering or chopping at the ice. A blow that misses the ice lands on the gutter, the fascia or the channel.
• Raking hard at the edge. Minnesota Extension says a roof rake can clear snow but may damage roofing materials. If you rake, keep the head off the gutter and fascia.
• Treating the symptom only. The lasting fix for ice dams is in the attic: air sealing and insulation. Ask a roofer or insulation contractor.

Snow slides and gutters

A pitched shingle roof sheds snow in slabs. After a sunny afternoon or a warm spell, a sheet breaks loose up high and slides to the edge, taking with it whatever is resting there. The taller and steeper the roof, the more speed it carries.

A clipped string rests on the shingle edge or the gutter lip, so a heavy slab can drag a section with it. That is one reason a seasonal lease includes repairs during the season. A permanent channel sits a step below the roof plane, with the drip edge above it, so a sliding sheet travels over it and drops off the edge.

Gutters are the weak spot on most eaves. They fill with snow, then ice, and a loaded gutter can sag or pull away from its hangers. Lights attached to a gutter go wherever the gutter goes. Lights fastened to the fascia board behind it do not. Our fascia versus gutter mounting guide covers that choice.

Two roof types behave differently:

• Metal roofs, including metal porch and bay roofs on otherwise shingled houses, tend to shed snow sooner and all at once. Read Christmas lights on a metal roof before planning those edges.
• Low eaves on ranches and over garages sit in range of snowblower throw and roof rakes. Point them out when we measure.

Wind and ice storms

Wind only damages what it can move. Along Lake St. Clair, from the Grosse Pointes up through St. Clair Shores, an east wind crosses open water before it reaches the first row of houses. In the newer subdivisions of Macomb Township, young trees and open fields do little to slow a west wind.

A clipped string is a long line of small attachment points, and wind works at every one of them. A rigid channel fastened along its length gives the wind nothing to lift. The part worth watching is the wire: the lead from the roof edge down to the power supply should be fastened along its route, not left hanging where it can slap the siding. Ask about that route when we measure.

When the ice comes

An ice storm coats the channel like everything else, and a glaze on the lens clears when the eave thaws. The real risk in a storm like February 2023 is overhead: limbs that snap under the weight of ice and come down on the roof edge. A falling branch can bend a stretch of channel the same way it would dent a gutter. Because the roofline is split into zones, a damaged run can be found without pulling anything else down.

If the power goes out, so do the lights. When it comes back, open the app and confirm your schedule is running before you assume anything is wrong.

After a storm: what to check

None of this needs a ladder, and please stay off one while the eave is icy. Work through it in order:

1. Look from the sidewalk in daylight. Follow each eave and rake. The channel should run straight and tight to the trim. A bow, a gap at a joint or a section standing off the fascia usually means something hit it.
2. Check the gutters and trim while you are looking. A gutter pulling away or shifted fascia is worth fixing for the house alone, and it shows where the lights may have taken a hit.
3. Light each zone on its own at dusk. From the app, turn zones on one at a time and look for dark or flickering stretches.
4. Walk the power route. Make sure the lead from the roofline is still fastened, not buried in a drift or plow pile, and that the outdoor outlet cover is closed.
5. Leave the ice alone. A glazed channel or a row of icicles in front of it is not a fault. Let it melt on its own.
6. Note the details. Write down the zone, roughly where the problem begins, and take a photo from the ground. If you call us to have the run looked at, that is what lets us find it quickly.

If a limb or wire is down on the roof edge, turn the lights off from the app, keep clear, and call the utility first if any line is involved.

Getting the channel up before the snow

All of this assumes the channel is in place before December weather sets in, which is why permanent lighting is an autumn install. Our calendar fills in order, so an early call gets the widest pick of dates.

For a sense of cost, a smaller two-story in Macomb Township often carries 100 to 150 feet of front roofline, and 100 feet comes to $2,200–$3,400 installed once. A two-story colonial on a village street in Grosse Pointe runs 120 to 180 feet, and at 120 feet that is $2,600–$4,100. Each winter after that, nothing goes up and nothing comes down.

For your own figure, photograph the front of the house square-on from across the road while the eaves are still clear of snow, then load it into our roofline measuring tool. Use the garage door as the scale reference and it traces the eaves and rakes right in your browser, with no upload. Then request an estimate with that number. We confirm your request within 24 hours. Before any channel is ordered, we confirm the footage and the mounting surfaces on site.

Where this applies

Typical roofline lengths and priced examples for these communities are on their own pages.

• Macomb Township
• Grosse Pointe
• St. Clair Shores

Sources

1. National Weather Service Detroit/Pontiac: U.S. Climate Normals Updated for the 1991–2020 Period weather.gov
2. National Weather Service Detroit/Pontiac: February 22nd 2023 Winter Storm weather.gov
3. National Weather Service: Winter Weather Warnings, Watches and Advisories weather.gov
4. U.S. Department of Energy: LED Basics energy.gov
5. University of Minnesota Extension: Dealing with and preventing ice dams extension.umn.edu
6. Building America Solution Center: Attic Air Sealing, Insulating, and Ventilating for Ice Dam Prevention basc.pnnl.gov