Benefits of open faced downspouts

Prevents popped downspout seams due to ice-build up.  The open-faced downspouts allow for ice expansion rather than having the ice pop the downspouts seams as it is expanding due to freezing temperatures.  Downspouts seams are typically behind the downspouts and when popped cause leaks behind the downspouts deteriorating walls they’re attached to.  Contributing to water penetration through the walls of the property especially with cinder block or concrete walls.  On metal walls, these leaks contribute to rusting.  On stucco walls these leaks contribute to stucco soaking up and falling apart.

Damaged industrial downspout due to ice

Allows for daylight/sunlight into the downspout.  In turn, the sunlight thaws the ice reducing the ice build-up in the downspouts and the weight of ice on the downspouts.  With regular closed downspouts the weight of the ice built up rips the downspouts out of the walls they’re attached to.  This usually happens when the temperatures get slightly warmer and the ice releases from the wall shifting all the weight to the downspout.  The damage these ice blocks could cause is unbelievable.  Anything below the downspout is a potential victim to the enormous crushing power of the ice blocks.  Could crush a vehicle or a person, push in the house wall or damage exterior fixtures such as a/c units or gas pipes and or meters.

Allows air intake, increasing the water flow capacity.  Preventing vacuum gulps at the gutter outlet and throughout the downspout.  Same reason why interior plumbers provide air intake, stink pipes, every so many feet.  The faster the water escapes through the controlled path of the downspouts the less chances of uncontrolled gutter overflows in the heavy downpours.  The gutter overflows could cause water into the property, landscape deterioration and or splash back onto siding contributing to rot or rusting.  Therefore, it is best to get all the water into the downspouts and out in designated areas.

Easier to inspect for clogs and easier to clean.  Given that the interior of the downspout is visible just with a glance, the clogs will be noticeable immediately.  In turn, they could be addressed right away.  When the clog is within reach with an extension post the ladders may not be needed at all.  Reducing the ladder related injuries.  Using an extension post the clogs could be broken up fairly quickly as opposed to the alternative when a closed downspout gets clogged they must be taken apart to unclog.  Taking apart closed downspouts for cleaning is a time consuming process that could add up in cost significantly over the years of maintenance.  In addition, the open-face downspouts will not clog nearly as much as a closed downspout since the open-face allows debris to come out of the front opening.

No, the water will not spill all over the place.  Water has surface tension capabilities where it sticks to the surface as much as possible.  Same reason why when pouring water on your hand it travels down your arm and finally drips at the lowest point such as your elbow.  The only areas where there may be an issues is at the elbows of the downspouts or at the outlet of the gutter.  Therefore, the elbows are not open-face and the downspout portion closest to the gutter outlet actually has a splash guard to prevent any splashing out of the downspouts.