It is very common for dormers and other roof structures that have gutters above the level of the gutters on lower portions of the roof, to empty onto the roof surface. The water is allowed to run on the roof surface and is collected by the lower gutters.
In this first picture one can see where the gutter has been cut off at the same pitch as the roof to let the gutter empty onto the roof surface. Note also that the valley also sheds its water down the roof surface as well—-as opposed to into the gutter.
This is pretty normal for a valley and there is no real alternative. When we add the water from the gutter at the same point it results in a lot of water running over the roof surface in a concentrated area that causes that portion of the roof to age prematurely—-as well as impact siding on the dormer. It can also maintain moisture on the roof resulting in more moss growth.
In this next picture we can see where the water is drained the other direction to a downspout that then empties onto the roof surface.
How about this one with the additional problem the roof step flashing not being properly counter-flashed by the siding? Water flooding from this downspout can easily find its way into the roof and wall structures.
Leaving the gutters off altogether is not usually a good option (unless the roof is very, very small) because the rain dripping off the edge will wear on the roof below. Everyone has seen the holes that can be eaten into the ground below roofs with no gutters—-you don’t want this to happen to the ground around your foundation and the same kind of pounding can take a tole on a roof below other sections of roof with no gutters.
So what are better alternatives?
One common solution which most people don’t like because it is considered “unsightly,” is to make the downspout continuous over the surface of the roof. Besides being unsightly they are always getting stepped on or otherwise damaged—-but still a better solution than just letting the water run across the roof.
This has been a long-winded way of getting to perhaps the best solution to this problem that I have ever seen (as long we are going to insist on continuing to use asphalt shingles as a means of covering roofs).
This metal tray protects the roof surface, is not easily damaged by klutzy inspectors, and gets the water to the lower gutter—and won’t clog with debris.
Now if I could just talk people into covering the whole roof with the stuff.
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Charles Buell, Real Estate Inspections in Seattle
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Do Charlie,
I’m wondering? (as long we are going to insist on continuing to use asphalt shingles as a means of covering roofs) what kind of roof do you recommend for a small house with a 12/12 pitch that wants to be energy efficient and green and environmentally friendly? I’d like to salvage roof water to water gardens etc. with out the pollution from asphalt/fiberglass shingles.
Glenn, there are lots of different metal roofs—from raised panel look to shingle look. There is no alternative for me.
How would you attach the metal tray to the roof? Also, what would you call that piece and where could you find it?
On the upper end the attachment is hidden under the shingles and on the lower end the tray is bend around the bottom shingles or edge flashing. These trays would be custom made by a gutter installation contractor.
My gutter drains onto lower roof…I attached a piece of downspout to run on the roof to the gutter below…how do I secure the downspout so wind wont move it or rip it off…it moves a bit..can I nail or screw into roof shingles to secure it with a strap?
Mike, it is typically adequate to connect a single length to the downspout at the top (which itself should already be adequately secured to the house) and then secure it to the lower gutter–without having to make any connections through the roof surface. Good idea to avoid that if possible but it could be done as long as any brackets are attached under the shingles instead of on top of them.
How exactly do you secure the downspout at the bottom where it empties into the lower gutter?
Most of the time it is not positively connected at all but if you wanted to because of high winds you could simply mechanically attach the elbow to the outer edge of the gutter. That said I prefer a tray to a downspout and that would simply extended past the roof edge and then folded under the edge of the roof under the drip edge.
I have a downspout from a dormer that empties onto a lower roof section. The shingles began to wear after 9 years and as a result I had a leak in my attached garage. We have not addressed the downspout yet, but at the point where the water empties onto the roof, we ran sheet metal under the shingles all the way down to where the water collects in the lower gutter. I have seen a few others that have done this. Although it won’t help the roof shingles, is it sufficient to protect from leaks?
Craig, it is not likely that this installation is going to be satisfactory in the long run—perhaps if it was ice and water-shield type material–but not metal. Every roof penetration of the metal is ultimately going to be a potential leak point. Running the downspout across the roof or installation of a tray flashing on top of the shingles is the best way to provide protection of the shingles if the downspout cannot be re-routed to a better location.
What about the depth of the upper downspout where it enters the lower gutter? Should it stop just at the top, half-way, or shoud it touch the bottom of the lower gutter?
Kathleen, I prefer the “tray” type crossing of the roof, but if you have to use a downspout then it should go into the lower gutter just enough to keep the water from flowing around the lower gutter—you don’t want it to block the lower gutter by having it in contact with the bottom of the lower gutter.
I agree with Charles on several points in this thread.
First, the cost of continually messing with an asphalt roof and the damage that it causes when things go wrong with them makes them more costly than they appear. I like metal roofs, but my personal house is a clay tile roof. Somebody mentioned energy issues with roofs, and it’s huge. Black asphalt roofs are like a solar collector in the summer. Metal has a reputation for being hot, but it actually reflects a lot more energy than asphalt and is usually a lower temperature. It conducts heat very well which is why it is hot to the touch. Tile, and specifically, clay tile, is much less conductive and has the added advantage of being in contact with less of the actual roof structure. Tiles major drawback is it’s immense weight. In any and all cases, it’s the underlayment that needs to be well installed and protected. The heart of the roofing system is the underlayment, flashing, and covering working in harmony together for a total system. Sorry I kind of got off track there…
Second, managing the water from the roof can be a major pain, but well worth the trouble to do it correctly. I don’t like it when gutter installers dump water from their gutters onto any part of the roof below. Begging for problems. Large capacity gutters properly installed with adequate slope, kept clean, into adequate spouts, and then getting that water away from the house. Your foundation does best when the water and moisture level is kept at a consistent level so the soils are not swelling and receding and heaving things around. That consistent moisture level is better leaning towards dry than wet. Saturated soil is far too plastic to support a house, and things will move.
Finally, while we are talking about material choice, I used 100 percent concrete board for soffit material here in hot Texas. This stuff basically ignores moisture, holds paint well, and doesn’t rot. It’s more expensive and harder to work with, but well worth the trouble.
Hope this helps…
Mark
I am curious about the condition shown in the first photo. I have two locations just like this. Is there any way to capture the water from the valley in that gutter? Maybe run the gutter to the adjacent roofline by angle cutting the gutter face and installing flashing under the first layer of shingles to funnel into the gutter? I am trying to prevent snowmelt from re-freezing in an area which does not receive much if any sunlight and causing ice damns.
The gutter installation company I had review this did not want to run the gutter to the adjacent roofline in attempt to capture the valley water. He wanted to put a normal endcap in place about 1″ short of touching the adjacent roofline.
Brian, that is perhaps the most difficult roof intersection to address adequately—especially when ice-damming is involved. If the run is very long, from the end of the valley to the lower gutter, it only compounds the issue. Honestly, the under-layment from the valley all the way to the lower roof edge should be ice and water shield for starters. On top of that, a wide tray, something like the one in the last picture could be inserted under the valley and run all the way to the lower roof edge. It must be wide enough to accommodate the amount of water running our of the valley as well as any over-shooting of the valley during heavy rains.
we are replacing the built-in gutters with k style and wanted to know your suggestion…
on the upper main part of the roof that has the chimney you can follow the valley and that intersection of the two roofs – gables coming together and we 100% want to catch the rain from that valley and then transfer it down to the funky lower gutter which also will be changing but that is for another story…
suggestions?
A question on the tray that helps with gutters draining to lower roof, is there a formal name to that tray and/or specs for the tray design online that one can refer to? Something you can show to gutter installation contractor to custom make. I would imagine in the business of gutters, roofing, home construction/remodel, not everyone is well versed in the trade. I don’t want some contactor saying “yea we can do that” but don’t fabricate the tray correctly to spec, or would like to have a way to confirm they know what to do when fabricating this tray and installing it.
In my area, I’ve not seen such a tray before, so I’d imagine it’s not common to custom build such. But I’d like to have one for my roof.
Any reputable gutter company can make these pans for you—very simple things really.
I was wondering, it’s tough to find that type of tray you have in your picture labelled “A tray to protect the roof from water damage”
any suggestions? all the ones I find are all large plastic ones that go on the ground and they seem quite large.
Sonia,
Any good roofing contractor can fold up one of these trays. I don’t know of any “readi-made” source of them because every circumstance where they are going to be used is so different. Someone should take on the idea of them though 🙂
Charlie
Charlie,
I have a two-story house in New England with basically a flat back but the second story overhanging the first story by 16″. There is a doorway to the deck in the middle of the back of the house. After snow melts, it drips down from the roof onto the deck and freezes, making an icy deck. I’m looking for a maintenance-free solution to the icy deck.
My first idea is putting a single 6′ gutter over the deck to divert water to the side of the deck. With the gutter two stories up, it will be really hard to get up there and clean it, so I’m wondering if it might be acceptable to have the gutter open at one end, so water and leaves just flush out naturally, rather than putting in a downspout that will clog and require cleaning. I could add a large piece of flashing on the fascia so rain flow doesn’t splash the fascia. I could even curl the flashing slightly to guide the water. I have seen many ads for gutter guards, but everyone says that they still need cleaning, just not as often. I’m looking for something that is really maintenance-free and won’t require me going out on a big ladder.
Thank you for your help.
Bob
Bob, these kinds of issues can be really hard to address satisfactorily—as I am sure have found. The deck would either need a bigger covering or perhaps a covering that could be removed in winter. A gutter guard is not likely to help as some amount of water always seems to get by them—although the roll type (like gutter helmet) might be satisfactory. Maybe deicing salts? Leaving the ends off so you can flush them with a hose is one option—or even removable ends with rain chains to control the water. Just throwing some ideas out there not knowing exactly what you have going on.
Charlie
Should a downspout run into a French drain, especially if there is a lot of debris from many trees in the gutter. Will it clog the French drain?
Diane, yes, over time the french drain could clog and to protect it, it would be prudent to install screens at the downspouts to help protect the French Drain. Keep in mind though that you will then have to be more vigilant about maintaining the screens clear of debris to prevent flooding of the gutters.
When installing a downspout that runs from the second story gutter to the first story gutter how much space should there be between the end of the downspout and the gutter? I have this system on the north and south sides of the first story, and the contract that installed the gutters and downspouts left barely 1″ space between the downspout and gutter on the south side my house and less than 1″ on the north side of the house.
Seems like an inch would be fine—clogging is always an issue and maintenance is necessary regardless the clearance.
My mother has a downspout flowing onto the roof of an addition. The addition is about 14 by 22 feet. The roof slope is approx 6 inches over the 14 feet. Sometimes she has water flowing over the side (back of house) I think in part from the downspout. The lot is also very wooded so we have an issue with leaves. I have tried the foam inserts from Costco.
Any recommendations? A neighbor recommended simply directing flow from the upper roof off the side (see photo). I assume a tray would not on a roof with such a slight slope.
Thank you
Try uploading your photo again—don’t see it.
how close to the ground should the downspout be ?
It should extend away from the foundation at least 5 feet or terminate in an underground drain that terminates at an approved location.
Our home had new gutters installed but they covered very little of the extension which has a lower roof. Doesn’t all of the roof need gutters? The contractor says that when the distance is short between the upper roof and the lower roof is not uncommon because it isn’t necessary to have gutters. Is this true? I live in Seattle.
I guess you would have to attach a picture for me to give an opinion.
Please find attached photos.
Does this section of roof drain over this edge? It does not look like it does. If it does it should probably have a gutter.
Additional photo.
It would be extremely unusual, and in my opinion not necessary to have a gutter on the roof behind the skylights.
I had read your advice and extended my downspouts all the way to the lower gutters. Will the areas where you have upper downspouts pouring water into the gutters need to be secured with more gutter hangers or they should be good with the current hangers? Will concentrated water flow push the gutter off the roof? Can one inch from the bottom of lower gutter enough to avoid flashing of water out of it during heavy rain?
I doubt the force of water on the gutter would be a factor but it might be a better question to ask a gutter installer. Most of these extension I see leave about 1 to 2 inches of clearance. All gutter installations can experience overflow issues in VERY heavy rains—but most of the time they behave properly.
I read this article completely about the comparison of newest and earlier technologies, it’s awesome article.
I have green discoloration on the main roof asphalt shingles from the open ended dormer eavestrough to the lower gutter. how about I secure some copper in the dormer gutter floor? will this help? Thanks
I do not know if that will help
Thanks Charles! Some of the questions about second story gutter into first story gutter were exactly mine and your answers have proven most helpful!
Whats the maximum Length & width I could go on the roof tray For the downspout?
I do not think length matters much but width between 12″ and 16″ should be OK