Home>Discussions>EXTERIORS>Installing gutters AFTER installing the drip edge
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Mastercarpentry
Re: Installing gutters AFTER installing the drip edge

The gutter should go between the fascia and the drip edge because this will stop all possibility of water entrance to the house save for overflowing gutters which is an avoidable situation. If you're not going to maintain them, don't install gutters. And something lost over the ages is that fascia boards should be painted on all 6 surfaces during the installation, not just back-primed leaving the joints unprotected or with only the visible surfaces protected. Metal over the fascia is not a good solution as there is condensation on the metal and it will collect at the bottom rotting the wood underneath it- I see this a lot. Even with fascia metal (perhaps especially so), the wood still needs to be sealed on all 6 surfaces.

Wood shingle strips (the 1X2 referred to here) should not be used on eaves where gutters are to be installed and a good roofer will pull them off before doing their work. If this exposes unpainted wood then it needs to be painted before the shingle molding covers it. They will also adjust the shingle over-hang for gutters where it should be shorter than if none are to be used. Furthermore, the shingle molding belongs under the roof underlayment, not on top of it as is the usual method. Think of this as how the whole system works:

Shingles catch the rain so it runs off. The underlayment is a secondary waterproofing under it just in case some rain gets through. Shingle molding above the underlayment will allow any water to get under it and contact the wood that we're trying to prevent which is the whole reason for roofing anyway. Yes, the underlayment should let that water run off safely but you penetrated it with the fasteners holding the shingle molding on so it's not as effective as it is supposed to be. Now that we've got all the water running off the drip edge of the shingle molding no matter what, let's keep it from finding it's way back to wood by having the gutter under it, not over it. If the gutter is left to overflow then wood is going to get wet anyway no matter how you do it and with that being the less likely situation encountered compared to having some water under the shingles, then that it what you plan for in the design since you can't cover both situations with one single approach. The gutter fasteners belong as high as possible so that there are no holes lower than they need to be so that the gutter can hold the highest water level possible before encountering a possible point of leakage. From the top, the roofing and guttering should be seen as a system, not individual components, where each part acts as a back-up for the parts above it. This will indicate what goes where and what should be done underneath everything.

Nothing is perfect and no matter what you do there will always be some risk of some kind of problem. Everything is a trade-off in some way. Good designs and their implementation always takes into account what the most likely problems are going to be and aim to mitigate them first, then dealing with secondary concerns after that. I've never seen a properly sized, properly designed, and properly maintained gutter overflow ever, and I've seen rainfall rates so heavy that they would be similar to what you encounter in a hurricane. The problem is that very few roof/gutters/downspouts are done properly as each trade involved does not think about the others, or the system was designed based on aesthetics over performance. So long as it's components are intact and in good condition, no roof or gutter should ever leak period. If it does, that means you missed something in the design and/or implementation of the system.

Phil

keith3267
Re: Installing gutters AFTER installing the drip edge

I agree with Phil on this 100%. He has done a better job of explaining than I did.

Tom-ip58
Re: Installing gutters AFTER installing the drip edge

Can the posters recommending roof drip edge over gutter address the situation when there is metal trim or capping covering the fascia? I believe the metal capping inhibits weathering of the fascia wood and extends its life in lieu of painting. I'll continue with my inexperienced description and theory so that posters may comment.

My fascia metal capping is formed in an "L" shape. The larger leg of the "L", whose height is nearly the height of the fascia board, is installed vertically so it slides under the roof drip edge. The shorter leg, maybe 1 to 1.5 inches or so, is horizontal and extends over the bottom edge of the fascia.

The roof drip edge extends over the fascia capping such that any water that runs off the roof drip edge also runs down the outside of the fascia capping and drops to the ground. The roof and fascia wood is protected.

In this case of fascia capping, the gutter should then mount on top of the drip edge which is then also on top of the fascia capping.

Under the clogged gutter/leader scenario, water over-flowing from the back of the gutter will contact the roof drip edge and be diverted down the outside of the fascia capping as previously described. The roof and fascia wood remains protected.

Thanks for your comments!

Mastercarpentry
Re: Installing gutters AFTER installing the drip edge
Tom-ip58 wrote:

Can the posters recommending roof drip edge over gutter address the situation when there is metal trim or capping covering the fascia? I believe the metal capping inhibits weathering of the fascia wood and extends its life in lieu of painting.
Thanks for your comments!

Were life only that simple. I've replaced thousands of feet of rotted fascia which was covered with metal, and I know that much of the wood under it was fine when the metal went on. The wood under the metal has to be dealt with at the start just as if it were not going to be covered, or the condensation on the back of the fascia metal will induce rot. All that fascia metal does is mitigate a need to keep repainting the fascia after it's installed and to provide support for the outer edge of vinyl soffit material. It's not a panacea. And it not often done properly either.

I know it's long-winded but I explained above why the gutter should go under the drip cap, metal fascia or not. Properly installed fascia metal will be as high or higher than the back of the gutter anyway and even if the gutter overfilled, the water level would not reach the high spot where the gutter might be as high as the fascia metal- it will spill out of the lower end(s) before that (where the gutter is lower than the fascia metal). Think about it.

Phil

keith3267
Re: Installing gutters AFTER installing the drip edge

I had a house once that had this metal cover on the fascia, it had to have it because the house was a shallow pitch tar and rock roof. The metal came down over the 2x10 fascia only about 2" and the bottom 1/4" flared out away from the wood so that water dripped off and did not wick back up under the metal cap. The house was 30 years old when I bought it and there was no evidence of rot on the top of the fascia so I guess it was done right when built. It did not have gutters.

eman
Re: Installing gutters AFTER installing the drip edge

Gutter apron is a wider strip of flashing designed to actually have the gutter slide behind it so it drops all the way into it. It puts 100% of the water into the gutter. Drip edge is a narrower strip that is flared outward away from the roof at the bottom so water wicking back under the shingles is shed away from the roof. It puts 99% of water into the gutter when everything is adjusted correctly. Gutters are tucked behind gutter apron. Apron is recommended for lower slope roofs where water is more prone to wick back under the shingles before gravity can carry it away from the roof edge. With drip edge the gutter is tucked back so it's rear lip is behind the lower lip of the drip edge but still hanging below it, and water is directed into the gutter by gravity. It doesn't actually get tucked between the drip and fascia. Gutters are replaced all the time on plenty of homes on roofs with drip edge installed without touching any other part of the roof. It really isn't a problem, just tuck it behind the bottom of the drip edge then screw the bracket into the roof deck above the drip. I just watched someone do it on my own house. This is not anything to be worried about. Just make sure they use hidden hangers that screw into the top of the roof deck so they don't have to drill holes in the front of the fascia and compromise the drip edge or fascia wrap. I would definitely be firm on that. They also don't pull out over time like screws and spikes in the fascia will.

My gutters are installed like this and I have watched them do their job flawlessly from my 2nd story window, with barely more than a couple drops of wind-driven rain sneaking behind them.

Brandon
Re: Installing gutters AFTER installing the drip edge

I work for a 3rd generation roofing company installing gutters and Phil has it on the. installing gutter over Eve metal is never a good idea wicking  will cause water To flow behind gutter  Rotting wood facia should always be painting to on all 6 sides and very thick on the ends Correctly installed in maintain gutters will never overflow not even close

Michael
Re: Installing gutters AFTER installing the drip edge

Regarding installing gutters behind, on top of or below a drip guard. I have a workshop attached behind my garage with a rolled roof that slants down from front of garage towards the workshop. Next to the garage and adjoining the house is a covered patio that extends back to the end of the garage.  There is a gutter at end of the covered patio that runs at a right angle towards the garage then runs the length of the workshop to the back end where it turns again and runs down the back of workshop ( this portion catches all the water running down garage and workshop rolled roof) where it all exist in a down spout at back of property.  Because of the rolled roof the workshop portion has a drip guard installed from the end of patio roof running the length of the workshop.

The portion of the gutter running from patio roof to end of workshop is only needed to handle the water from patio roof to get it to the back of the property.

I recently had the workshop portion of the gutter replaced. A couple of months after this (this work was done in the winter) I entered the workshop to find major water damage to the ceiling and walls.  I climbed up to see what the issue was and discovered that the gutters had been installed behind the drip guard.  The drop guard was pulled out into the gutter and at each hanger it was cut and bent up so the hanger could be installed.  It was clear what happened.  The gutter had leads and sticks that had created a blockage about half way down the run from the end of patio roof to back of shop at one of the hangers. As the water backed up at this point and filled the gutter the water ran back into the buildings ceiling since the drip guard was no longer protecting this area.  This also kept the gutter from over flowing which would have been a sign of a blockage in the gutter.

I questioned the installation of the gutter. To me it was totally the wrong way to install the gutter in this situation.  Had they installed the gutter on top of drip guard this would never ever have happened.  The water build up would have run over the front edge of gutter and any water that leaked behind gutter would have run down the drip guard. 

Most of the replies here have stated to install gutter under drip guard. Maybe my situation is unique, but I don't see a good reason to violate the protection of a drop guard.  A drip guard is there to prevent water from getting into the structure where the roof meets the facia.  This is gone by installing drip guard under the roof material and running down the facia. By installing the gutter behind the drip guard you have now provided an opening for water to get behind the drip guard and into the structure.  At every hanger the drip guard will know provide zero protection and in fact become a major opening for water. You might as well just remove the drip guard because it will no longer be providing the protection it was designed for.

 

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