Wind and Hidden Hangers: Keeping Gutters on the House

How wind attacks a gutter

A gutter is a long, open channel bolted to the edge of a roof. Wind can work on it in several ways:

• Uplift under the front lip. Wind flowing up the wall and over the eave pushes up on the bottom of the trough, prying it away from the fascia.
• Pressure on the face. Gusts push directly on the front, flexing the trough between hangers.
• Vibration. Repeated flexing slowly loosens fasteners, especially in soft wood.
• Debris impact. Branches and objects hitting the trough bend it and tear hangers.
• Downspout leverage. A loose downspout acts like a lever on the gutter outlet.

In extreme events, nothing at the roof edge is safe. The NWS Corpus Christi summary of Hurricane Harvey lists a peak gust of 145 mph at the Aransas County Airport in Rockport (NWS Corpus Christi, Major Hurricane Harvey (Aug. 25–29, 2017)). But most gutter failures happen in far more ordinary storms, where better fastening makes the difference.

Spikes and ferrules versus hidden hangers

Older gutters were often hung with long spikes driven through the front of the trough, through a tube (ferrule) and into the fascia. Spikes rely on friction in the wood. As the wood dries, shrinks and swells through seasons, spikes back out. Each one becomes a loose pivot point.

Hidden hangers clip inside the front lip and screw through the back of the gutter into the fascia or rafter tails. Screws hold far better than spikes, and the clip stiffens the trough. Most modern seamless systems use hidden hangers.

Spacing matters

Texas A&M AgriLife's guidance on gutter installation suggests a hanger about every three feet (Texas A&M AgriLife Extension, Rainwater Harvesting: Conveyance (gutters and downspouts)). Wider spacing lets the trough flex more between supports, which loosens fasteners and lets debris weight sag the run. On exposed elevations facing open water or long open lots, tight spacing is worth asking for in writing.

Screws and what they go into

• Fastener material. Near salt, stainless or coated screws compatible with the gutter metal outlast plain steel, which rusts and loosens.
• Length. Screws should reach solid wood behind the fascia face, ideally rafter tails where possible.
• Solid wood. Screws in rotted fascia pull out. Damaged boards need replacement before hanging gutters. See fascia and soffit.

Downspout straps

Downspouts are often the first part to come loose. A single strap near the top is not enough. Use corrosion-resistant straps every few feet, a secure connection at the outlet and a strap near the bottom. On raised homes with long drops, add more. Downspouts that swing in wind tear the outlet and pull the gutter with them.

Gauge and stiffness

Thicker aluminum or Galvalume troughs resist flexing and denting. On homes with high exposure, a heavier gauge combined with tight hanger spacing produces a much stiffer system. Ask each estimate what thickness it uses.

The roof edge

A drip edge or gutter apron that laps into the trough sheds water into the gutter instead of behind it, protecting the fascia that hangers depend on. When roofs are replaced, it is common for drip edge to be installed incorrectly in relation to existing gutters. A quick check after any reroof is worthwhile.

Signs your fastening is failing

• Spike heads sticking out from the trough face.
• Gaps between the gutter back and fascia.
• Sections that bounce or rattle in wind.
• Standing water in sags between hangers.
• Downspouts that swing or have pulled from the outlet.

A quick ground-level wind check

You can learn a lot without a ladder. On a breezy day, stand back from each side of the house and watch the gutter line. A sound system looks still and straight. A failing one shows a slight bounce at certain sections, a visible wave along the front lip or a downspout that rocks at the top. After a front passes, walk the perimeter and look for hanger screws or spikes on the ground, small bends in the front lip and fresh gaps at the fascia. Note those spots and photograph them; they are exactly where a repair visit should start.

Paperwork note

The Texas Department of Insurance lists repairs or replacement of gutters among projects that do not require a windstorm inspection in the designated catastrophe area (Texas Department of Insurance, what you need to know about windstorm inspections). That makes re-hanging or upgrading gutter fastening a straightforward project. Roof-edge work that involves decking or structural framing is different, so ask your agent if your job goes beyond gutters.

Upgrading an existing system

If your gutters are sound but hung on spikes, a re-hang with hidden hangers, new screws and added downspout straps can extend their life and improve storm performance. If the troughs themselves are corroded or undersized, it is usually better to replace and fasten everything new at once. See gutter repair and the estimate factors page.

Soft wood behind the hangers? Read about fascia and soffit work before re-hanging.

Sources: NWS Corpus Christi, Major Hurricane Harvey (Aug. 25–29, 2017); Texas A&M AgriLife Extension, Rainwater Harvesting: Conveyance (gutters and downspouts); Texas Department of Insurance, what you need to know about windstorm inspections.