We have been in the business of repairing pre-engineered metal buildings since 1996. That’s all we do, pre-engineered metal building repairs. One of the most difficult repairs is replacing an internal gutter. We have a documented the installation procedure for replacing internal gutters to explain why they leak and demonstrate a couple of recent projects.
Internal Gutter Sealing Project
The Metalguard team replaced 9,700 linear feet of internal gutter on this project. See below for the a deep dive into the crucial details to keep an internal gutter from leaking. This building is 1,450 ft long.

Internal Gutter Project
Crucial installation steps for leak free internal gutters






Internal gutters at a parapet wall

This photo shows the installation of a metal gutter at a parapet wall. The steel panels adjacent to the wall are replaced to complete a waterproof seal.

The team carefully installs the new internal gutters to stop the roof from leaking.

Above, this photo shows the completed internal gutter installation. This gutter will extend the life of the metal building.

Below are pictures from a few different buildings. Prior repairs by other contractors were not successful. They tried pouring tar or other products into the gutter and sealed the fasteners on top of the gutter.
Unfortunately for the building owner, that didn’t solve the problems because that’s not why internal gutters leak. Sure, some times they leak at a fastener or one of the gutter seams. However, most of the time water enters the building from under the roof panel.


The roof panels have a “profile” to give the panels strength. The profile includes high ribs. The most common reason internal gutters leak is due to water “splashing”. When the water hits the internal gutter, it splashes, just like a waterfall landing on rocks. When enough of the drops get in it starts to drip. With a heavy rain it may overflow the gutter and the water flow gets heavier.
Below are some pictures we have taken as to what the inside if the high ribs of the panels have looked like





Above depicts a roof replacement that includes an internal gutter. We have documented the replacement process below.





Closure is installed at the eave. First, two runs of butyl caulk tape. Then, two runs of closure. The closure is 3’ long and matches the profile of the roof panels. The have a connecting joint, the connecting joints are alternated and provides a backup waterproofing barrier.



Urethane caulk is applied to the top of the closure

The roof panels are secured in place over the top of the closure.

This is what the finished product looks like.


Sometimes we only need to replace the panels at the eave.


The picture above is a standing seam roof with an internal gutter. A standing seam internal gutter replacement is a little more challenging than an R panel screw down roof. There are clips that hold down the panel seams.