One System, Not Two Jobs
The single biggest mistake we see in Colorado roof replacements is treating the roof and gutters as two separate projects. They are one interconnected drainage system, teammates in the battle against water damage. When a new roof goes up over old or damaged gutters, water can overflow, pool near the foundation, or run behind the edges. Replace one without the other and you leave real structural protection on the table.
Old gutters undercut a brand new roof in ways most homeowners never notice until damage shows. Water that should be captured and carried away instead saturates fascia, erodes soil near the foundation, and reappears in basements. A roof replacement is the natural window to evaluate the entire drainage chain, from drip edge and pitch down to where the downspout finally releases water at grade, far from your home.
Sequencing And Fascia Inspection
Order matters. In almost every full roof replacement, the roof goes on first and gutters follow. During tear off, the old gutters actually earn their keep by catching debris and shielding your siding. Once the new roof is complete, our crew fits new gutters precisely to the fresh roof edges so everything lines up the way it should.
Sequencing this way protects the drip edge, which must sit under the roofing felt and over the sheathing and fascia board to steer water into the gutter. Install gutters first and the drip edge cannot be positioned correctly, which lets water run behind it and rot the fascia. This is exactly why the roof first approach is the most practical, durable method.
Tear off is also the one clean shot at inspecting the fascia for rot before anything covers it up. Any soft or damaged sections get replaced, then new fascia boards are primed and painted before gutters ever attach. Skip this window and the new installation is already living on borrowed time, hidden behind gutters that hasten the very damage they should prevent.
Drip Edge And Gutter Pitch
Drip edge is the metal flashing along the roof edges that hands water off to the gutter. Missing or poorly installed drip edge is one of the most common sources of avoidable long term damage on shingle roofs. Without it, water curls behind the gutter, saturates fascia, peels paint, and rots wood beyond repair.
The consequences compound. Fascia rot leads to roof deck deterioration at the edges, and as the fascia loses structural integrity, gutters begin pulling away entirely. In Colorado winters, missing drip edge also raises ice dam risk. We fasten drip edge every 12 to 16 inches with roofing nails so the roof to gutter handoff never fails.
Pitch is the error nobody sees until water pools. The standard is a half inch drop for every 10 feet of run toward the downspout. Set a gutter perfectly level, a surprisingly common mistake, and water simply sits there. Too shallow invites pooling, added weight, and ice buildup. Too steep lets water outrun the outlet in storms.
Standing water in an improperly pitched gutter is more than a nuisance. A five inch gutter filled with water weighs roughly two pounds per linear foot, and that dead weight pulls hangers loose and stresses fascia over time. In Colorado, that same standing water freezes and thaws through the winter, working against your shingles and roof edge. On long runs of 40 feet or more, we slope the gutter down in both directions from the middle with a downspout at each end, so water always has a clear, controlled path to leave the system rather than pooling in the low spot.
Pitch also has to account for your new roof profile. Upgrading to architectural shingles raises the roof's profile and increases the velocity of water hitting the eaves, which can overwhelm a five inch gutter that was fine for the old roof. Moving up to a six inch K style gutter, which holds roughly fifty percent more water than a five inch, keeps that faster runoff contained. This is precisely the kind of detail that gets missed when gutters are treated as an afterthought instead of part of a system engineered around the finished roof.
Downspout Sizing And Valley Placement
Downspouts decide how fast water actually leaves the system. Undersized or under placed outlets create backpressure that overwhelms even a generously sized gutter channel. The baseline is one downspout per 30 to 40 linear feet of run, but that is a starting point, not a rule. Roof complexity, run length, and valley locations all push the math in different directions.
Valleys are the consistent blind spot. A downspout at or near a roof valley must handle far more volume than one serving a flat run, because valleys concentrate runoff from two roof planes. Installers who treat a valley placement like a standard placement are undersizing the outlet from the start. We size outlets to the water each section actually delivers, not to a generic spacing spec.
Sizing carries real capacity. A 2 by 3 inch rectangular downspout can serve up to roughly 600 square feet of roof, while a 3 by 4 can handle up to about 1,200. Given that a 1,000 square foot roof produces around 600 gallons per inch of rainfall, the difference between the two decides whether your system keeps up during a Colorado cloudburst.
Ground Termination Nobody Checks
A downspout is only useful if it releases water far enough away that it cannot seep back toward the foundation. Extensions and thoughtful placement matter as much as the downspout itself. Terminate right at grade with nothing in place and you invite erosion and moisture pushing back against the footing.
We route water to a sloping final grade at least 5 feet from the foundation, or into an underground catchment system at least 10 feet out. Splash blocks, subsurface drainage, or pop up emitters all have their place. Extensions themselves need a minimum quarter inch per foot slope so water keeps moving away rather than stalling near the house.
One firm rule across the Front Range: downspouts drain to grade and are never tied into sewer lines, which is illegal in most local jurisdictions. This last foot of the drainage chain is the piece homeowners forget most, yet it is where foundation problems either begin or get prevented for good.
Colorado weather demands a system built for local reality, not a generic spec. Gutters here fight ice dams through snowy winters and swallow the intense rainfall of summer thunderstorms. When a roof pitch exceeds 6/12, water rushes the eaves at high velocity during cloudbursts, so we recommend six inch gutters paired with 3 by 4 inch downspouts for rapid drainage. That same configuration is particularly effective at mitigating ice dam buildup at the roof edge.
Snow load and hail shape the details too. In heavy snow areas, including much of the Front Range foothills, we tighten hanger spacing to 24 inches instead of 36 to carry the extra weight of snow and ice. Galvanized steel resists dents well during June hailstorms but needs joint maintenance against corrosion over time. Rapid mountain snowmelt also produces volumes standard residential gutters were never sized for, so systems at elevation get sized to the roof's actual drainage load.
Frequently Asked Questions
Should gutters be replaced with a new roof? In most cases, yes, especially if your gutters are near the end of their service life. Aluminum gutters typically last 20 to 30 years and copper 50 or more, but gutters at 15 to 20 years old are approaching the end of their run. Since the roof replacement is the ideal access point for inspecting fascia and setting drip edge correctly, pairing the two protects your investment and avoids fitting new gutters to an old, mismatched edge.
Do gutters go on before or after a new roof? After. The roof is completed first so the drip edge can be installed under the roofing felt and over the sheathing and fascia, directing water into the gutter. Old gutters stay on during tear off to catch debris and protect siding, then new gutters are fitted to the finished roof edges. Reverse that order and the drip edge cannot be positioned properly, which allows water behind it and eventual fascia rot.
What is the correct gutter pitch and downspout spacing? Aim for a half inch drop per 10 feet of run toward each downspout, with roughly one downspout per 30 to 40 linear feet as a baseline. Do not install gutters level, since water will simply pool and add weight. Colorado's WUI code, effective July 1, 2025, also requires non combustible gutter materials in designated zones alongside Class A roofing, so material selection now matters as much as pitch in fire prone areas.
