The Magnolia Overflow/Screen Box

The Overflow box is an original innovation of Magnolia’s that serves two purposes. It was first conceived as a method of moving the downspout outside the perimeter of the underdeck so that a screen could be installed to protect the area inside the coverage of the underdeck.

Later we adapted the Screen box to an Overflow box. This was to accomodate our customers who wished to direct the downspout from the underdeck to empty into an underground drain. 

Often the underground drains will become clogged due to the use of improperly installed corrugated pipe. Water will then back up the downspout and onto the underdeck. 

The trap door on the end of the overflow will open before the gutters fill and release the excess water onto the ground before it reaches the topside of the underdeckalt

Here is an example of rainwater flowing out of the joints in a downspout due to a clogged underground drain.


This is a typical installation of the overflow box. Note that the downspout placement would not interfere with the installation of a screen.