Rain, Rain Go Away: Making Sure Your Roof Has the Proper Drainage System

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Posted on May 24, 2019

Rain, Rain Go Away: Making Sure Your Roof Has the Proper Drainage System

If a roof was a superhero (and, given its protective abilities, it kind of is) then its arch nemesis would definitely be water damage. When water breaks through your roof’s barrier and starts pooling beneath the shingles, or when it gathers around the foundation of your home, it’s only a matter of time before that damage makes itself known in moldy, soggy, expensive ways.

Drainage systems play a vital role in your roof’s overall durability, and it’s important that the drainage system on your house is the proper drainage system for your roof. Proper drainage will not only help water slide off of your roof without pooling beneath shingles, but it will also divert the water away from your home, which can help minimize water-related foundational damages. Roof drainage systems are complex, but when properly taken care of, they are invaluable.

Why Water Run Off & Roof Drainage Problems Should Be Taken Seriously 

Your roof’s drainage system is what helps keep water from becoming water damage. Between rain, snow, and melting ice, there’s weather-related potentially-damaging water on your roof all throughout the year. Having the proper drainage systems installed and maintained can help reduce the damages of mold, wet basements, and even weakening foundations.

The roof drains and gutters in your roofing system have been designed to redirect water away from your home by utilizing gravity. These drainage systems stop the flow of water during a heavy rain from backing up into the roof, which reduces the potential for interior water damage. By diverting melting snow off of the roof, these drainage systems also help relieve some of the weight-related stress from your home during the winter months.


Gutter Systems: Traditional gutter systems can be found on most residential houses. This drainage system works for roofs with a slope greater than 2%. Roofs with less than a 2% slope are considered to be flat roofs and require a different type of drainage system. Drainage systems the use gutters are inexpensive, but they require frequent cleanings because the smallest amount of blockage can cause a gutter to back-up and overflow. Gutters run along the bottom edges of the roof, and they typically have downspouts mounted to the side of the home to divert water away from the foundation.

Scupper Drains: Because flat roofs lack the necessary slope for gravity to pull the water into a gutter system, scuppers are more commonly used on flat roofs that have a perimeter barrier around the edge of the roof. Scuppers are essentially open holes cut along the barrier (or parapet) of the roof. They are cost effective, easy to maintain, and can improve the aesthetic of a home. The low slope of the roof helps drain the water out through the scupper, where it may then drain into a downspout or an extended chute that funnels the water away from the building. It is important to check the downspouts often, as they are vulnerable to clogs.

Inner Roof Drains: Another popular drainage system for flat roofs are inner roof drains. These drainage systems have a lowered channel that collects water and directs it into a hidden drain, which leads to an underground drainage system. They work similarly to the drain in your showers and sinks. Because of their hidden nature, inner drain systems are popular, attractive, and they are resistant to freezing. However, they do rely on careful and continuous maintenance in order to avoid problems, and –should the system sustain any damage– a professional roofing technician is required for repairs.

Your roof’s drainage system can consist of gutters, interior drains, scuppers and downspouts. Given their design, it is easy for different features of the system to become blocked up with debris (trash, leaves, dirt, etc.), which can reduce the efficiency of the drain. It is important to check on your roof’s drainage system in order to ensure everything is in working order.

Improperly sloped gutters or misaligned downspouts can also result in the accumulation of water, which can damage your gutters, roof, and foundation.


Can You Slow Down Water on a Roof? 

Since the speed of water usually relates to the intensity of rainfall and the pitch of your roof, it’s not easy to change how fast its flowing (without changing your roof). The key to dealing with water overflowing in your gutter (or overshooting it altogether) is proper diversion. The solution may be as simple as adding a new system that is wider and higher than your current gutters. But there are a few other things to consider.

Other reasons why water will overflow or overshoot your gutters:

Too much overhang with your shingles or metal sheets

Not enough diversion for roof valleys

Not enough downspouts

Gutters need to be cleaned

If you suspect you have too much overhang with your shingles or metal roofing, check to see if they extend more than 1 inch past the roof. If so, they are probably overhanging the eaves too much. If most of your issues are happening around your roof valleys, you may want to install a special diversion system built specifically for roof valleys that can help spread out or capture more water.

Helping Your Roof Help You:

  • Twice a year, inspect and clean your roof’s drainage system. If your system is habitually clogged by tree leaves or debris, these inspections should be done more often.
  • Clean accumulated debris (tree leaves, sticks, trash, roof granules) from the roof regularly to avoid it clogging your drainage system. Roof granules, particularly, can alter the slope of the gutter which inhibits the gravitational flow of the water.
  • Trim any trees and keep them away from the roof to avoid branches rubbing against the roof and dropping leaves which can clog gutters and drains.
  • When checking your gutters, be aware of any long-standing water. If there is no clog causing it, long-standing water could be a sign that the gutter isn’t properly sloped toward the downspout.
  • After any severe weather, check your roof’s drainage system for leaks and confirm the system is properly secure.
  • Check that all downspouts are diverting water away from your home so that water is not allowed to accumulate around the building.
  • In areas more prone to hurricanes and heavy storms, ensure your gutters are properly anchored by wind-resistant gutter straps.

Having the proper roof drainage system for your home is important. Whether your home has gutters, scuppers, or an inner-roof system, the proper drainage system will ensure that water, snow, and melted ice are directed off of your roof and away from your home. Annual upkeep is imperative to the overall health and efficiency of your roof’s drainage system, so it’s important to make sure the system is unclogged, in its proper place, and that it does not have any leaks. Taking care of your roof’s drainage system is one way to make sure your roof can keep protecting your home like the superhero it is!

At Honest Abe Roofing we make sure to put the correct systems in place so your roof has a proper drainage system. Call Honest Abe Roofing today to get a free quote.

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