How To Seal Internal Gutter?

[Nesian]

Hi,

My fathers house has a problem with Internal guttering. We thought we had fixed the problem when we got a bigger down pipe installed but if we have a good hail,sleet or snow shower the gutter just fills up and then it rains and it ends up inside the house.

We have some gutter guard over it but the holes are too big to keep out hail or snow.

I was wondering if anyone knows how I could effectively seal where the arrows are in the photo so if the gutter does fill up it won't pour into the house.

Any ideas welcomed!

 

[xdave]

I am trying to work out the scale of the photo to see how big the gutter is. Is the roof on the right a self-supporting polycarbonate one? What are the gutter dimensions, length of that run and the size of the new downpipe? Does the downpipe drain correctly (no blockages in the drain)?

Is the problem only during hard precipitation (snow/hail/etc) or does wet (rain) produce the same results?

If it is only during hard precipitation then a raised fixed cover might help, with a guard fitted on the roof side. It might just move the problem up the roof though.

Are you certain that the water getting into the house is due to overflow from the gutter? Have you actually been up there when it occurs to check the levels? If the roof is at a very low pitch it could be water flowing back under the edge rather than running off and running down behind the gutter. Low water volumes can exacerbate that scenario, particularly if there is ice present, which you would get if there was standing snow and a warm roof surface.

Putting a drip edge on the roof would help if it was that, but you'd need to seal well around the raised parts to avoid just moving the problem.

If the roof is not flat/solid and is slate/tiles then sealing where indicated will just move the problem up to the first row of joints. If the problem is genuinely that the gutter cannot handle the volume then it either needs to be bigger (difficult here), at a greater fall (again difficult here) or the downpipe needs increasing further. If it can't handle the volume because it gets physically blocked with hard precipitation then that cover idea may help, but it would be worth confirming first-hand that that really is the problem.

 

[Nesian]

Hi,

Thanks for your reply!

I will include a link here for a video of the roof as is so you can get a better idea of scale etc...

http://www.youtube.com/watch?v=NvT7h5QCXE8

Making the gutter bigger or adding a greater fall are both non options.

The down pipe should be big enough to handle the water and we had it enlarged only a few months ago (as well as the gutter in the photo) as we thought that might be the main culprit (blocked drain).

Downpipe goes down through gutter into a overflow box



It only ever overflows when there has been torrential rain storms when it is really really pouring down or when there has been hail or snow so we are pretty sure that it's just not handling the amount of water and when the hail or snow fills up the gutter it makes things worse (it snowed a day ago).

When we got the gutter and downpipe enlarged a few months ago we thought that was the end of the problem and we even installed a new ceiling inside so my dad was gutted to see water dripping through today. The only good thing is that it wasn't anywhere as bad as usual this time round so I'm pretty sure the enlarged downpipe has helped.



I'm basically just trying to figure out a way to fix it that isn't going to cost an arm and a leg and trying to seal it somehow was the only thing I could think of?

Any further insights or ideas are appreciated.....

 

[xdave]

Thanks for the video, it makes it much clearer.

If it happens during torrential rain then it does sound like it is caused by sheer volume, and as you've said the hard kind just makes the problem worse by taking up more volume for longer and releasing more water when it melts.

There seems to be a large roof with an area of 100's of square metres on the other side of the wall during the later part of the video. Does that roof drain into the same gutter via that white pipe approx. 1 metre to the left of the downpipe?

Is the water appearing on the inside concentrated in the same area as the downpipe and where there is that small step in the wall, or is it more evenly spread along the entire length of gutter? Depending on what comes out of that white pipe (what is it for?), a large volume of water could build up due to the restriction caused by that step which could cause the gutter to overflow along that section. Water always finds its own level except where there is a force resisting flow, then you can get quite surprising rises in level over a fairly short distance.

If that white pipe discharges a lot of water you could (assuming you are responsible for draining it in the first place?) move it over to the downpipe itself with a hopper box to settle and reduce the restriction. Or as the downpipe seems to be on the edge of the building is there any way it could be replaced with something that comes down its own pipe to the drain to remove it completely? Of course if that white pipe discharges nothing then it won't make any difference... but reducing the restriction at that step by straightening the internal corner off would likely help in any case.

 

[Nesian]

Thanks for the reply.

I'm not entirely sure what the purpose of that white pipe is or if it even works because I don't recollect seeing an entry point for the water on the other side but I will have to double check. Problem is that the weather here is absolute crap and blowing like a storm so I don't want to jump up and have a look.

Off the top of my head I am thinking that it is functional because the main leak point inside is close to where that white pipe points down to but as I said I'm not even sure if it's functional so I'm just guessing but will check it out when I can and get back to you.

Thanks for the good ideas so far.....

 

[Nesian]

I'm pretty sure that white pipe is non functional. I put my camera on a pole and swung it by the roof today and there is no inlet on the other side of the gutter so I'm not even sure why it is there.

You brought up an interesting point about that little step.

It hailed today for about a minute so I went outside and with the camera and you can see on the video how just that small amount of hail has already built up in the gutter. I can easily imagine how the gutter could easily clog up by that step with hail and snow and cause the water to backup then overflow.

On the video you can see how the hail is closer to the camera and yet further down there isn't so much so I'm thinking it's washed down to that step. Luckily it only hailed for that short period today but I can imagine if it did that 3 or 4 times over a short period those gutters would be toast.

Question is, what to do and how to do it?

http://www.youtube.com/watch?v=I4Z2YJzyCgQ

Any ideas?

 

[xdave]

You mentioned that the 'main leak point inside is close to where that white pipe points down'. Whilst that video doesn't appear to show anything on the otherwise of the wall, the pipe must have been fitted for a reason. It is too high up to be an overflow or gravity fed drain from the property below, but it is angled in such a way that the person who fitted it seems to have expected water to come out. I don't know enough about the building codes for NZ to know if is some sort of approach for venting, etc? Puzzling.

When it is safe to do so could you get to the pipe and have a further investigation? An inspection camera would be ideal if you can't see the other end and have access to one. Does it look like the wall on the other side has been repaired to indicate it was once through the wall but since disconnected?

If it is worse during snow and hail then putting a physical guard (normally tensioned wires or mesh) across the entire length of roof approx. 6 inch/150mm back from the gutter edge would prevent slip down the roof getting into the gutter. A short ledge over the gutter itself that drains towards the roof would prevent it falling directly into the gutter. Those could both help in that scenario, but as it happens during really heavy rain as well it won't solve your problem completely.

If water is coming in through that gutter the cause needs addressing. You can try and seal between the gutter and the underside of the roof sheets but it won't be a permanent fix and doesn't address the cause. One temporary fix could be to clean thoroughly and gun a suitable flexible sealant into the gap between the angled top of the gutter and the underside of the roof sheet, then prime with bitumen paint and fit a strip of bitumen-based flashing product to bridge across from the underside of the roof to the side of the gutter. This might buy you some time to investigate the cause and get a permanent fix in place, but it will fail eventually.

With regards to the step, anything fitted across the internal corners to 'round it off' and reduce the friction would help. A hard flashing product could be dressed to fit such as lead or aluminium - it wouldn't need to be watertight (and likely wouldn't be) - it is just to reduce the friction and help the water to flow more efficiently.

If it rains heavily, is there any way you could get your camera/pole back up there to capture the flow? I've used a cheap web cam under a lunch box before to find a leak when access has been difficult.

When you had that short section of gutter replaced and the roof edge brought back, did the guy/persons doing it identify the actual cause, or were they just there to treat the symptom?

 

[tim00]

Lots of good suggestions above. My 10 cents is:
1. Dont go on any roof thats wet esp. if its raining or windy.
2. Go up in dry conditions and water test with a hose pipe.Observe how it flows and where.
3. How many outlets/downpipes does this length of gutter have?

 

[Nesian]

We actually had a couple hours of no rain today so I managed to get up on the roof and have a closer look.

The white pipe does indeed come from the other gutter. The inlet is actually under the overhang of the roof on the other side so you can't see it.

http://www.youtube.com/watch?v=1Y8UHdiKYnk

As you can see in the video I put the hose roughly half way down the roof on one side to see how the water flowed and although it only looks like it was dripping through the white pipe on the video, it was actually a constant stream of water coming out of the pipe, you just can't see it properly.

So I imagine when there is a torrential downpour that there is a heck of a lot of water being pushed through the white pipe to the other side which is already struggling to handle the amount that it's getting causing the gutter on that side to overflow and enter the house. Even worse when hail gets washed down there too. I probably made it worse as there was a build up of moss around the inlet so now the water will be flowing even more....

Would I be best served to cut the white pipe off as in the picture (as it won't rotate or move currently) and add another elbow and run some pipe down to above the down pipe so the water basically runs straight into it?








Seems crazy for a roof that size to have only 2 down pipes!

Thanks for the help!

 

[tim00]

No, dont go cutting any pipework. You would only transfer the difficulty to another area. The upper roof requires it's own outlets - a job for a pro metal worker, unless plumbers undertake this kind of work in NZ.

It's always bad practice to discharge from one level to another. The roofing arrangements appear to be of shockingly bad design.

My suggestion: leave everything as is, and have new outlets installed, then wait and watch and see.

 

[tim00]

As an aside mate, i've got all the time in the world for New Zealanders,
unpretentious, hard working, get-up-and-go people with generous hearts. I think also: Charles Upham and the Maori battalions, and Wacka Nathan, who i saw back in the day, he could have been the greatest except for injury.

 

[xdave]

Is that second area of roof (where you were running the hose pipe) your roof as you might not have responsibility to drain it, or at least you might not have to pay for any repairs if the discharge from that roof is causing your property damage. Of course if it is your roof or the whole thing is shared then it won't matter... (NZ laws may be different so if that might be relevant you'd need to seek local advice if it is not your roof.)

With regards to the white pipe...

In torrential rain that pipe will likely discharge at full capacity straight onto that step in the wall which will cause it to both run up the wall a bit (and probably under the roof edge), as well as creating a lot of back current.

You mention that it is crazy that a roof of that area is only served by two downpipes. Indeed it is, but does this mean there is an additional downpipe to a drain from the second roof area, or were you referring to the white pipe as the second? If that roof does drain elsewhere it would be worth looking to see if that white pipe could be removed and (as it must have been fitted for a reason) to increase the size of the second downpipe to offset the loss.

If there is not a second downpipe going to a drain then one should be installed. It might not be that intrusive to do so. It looks like you could punch out through the right hand end wall at the upper roof level and run a new pipe down to the ground from there. If you fed it into your existing hopper by the door then that box would overflow during the same levels of rain that currently causes you problems as the discharge from the second roof would actually be increased quite a bit, so it would need to go to a drain via its own route. If you are lucky there may be a storm/rainwater drain chamber nearby that you could have the new pipe run to underground. The possibilities for fitting a second downpipe is something you would need to discuss with local tradespeople because there is a lot to consider and any work undertaken may be subject to local building codes.

If you move the discharge over the downpipe as you have shown that would make a difference but it is trying to treat the symptoms and not the cause. If you have no other choice and need to get a low-cost DIY change in asap to protect the property then I would change your idea slightly to include a 90 degree bend downwards again directly above the pipe (or 2x 45s), and continue it down to a couple of inches under the roof level/top of the gutter. That way when the gutter is at capacity the additional volume would still cause capacity problems, but the turbulence caused would be much less so that whole length of gutter can help to hold the excess. This change is what is politely referred to as a 'real bodge' and should only be considered a temporary adjustment to mitigate the immediate damage being caused. If during exceptionally heavy rain the entire capacity of that gutter is exceeded it could overflow along its entire length and spread the damage being caused.

The only reason I would even suggest that as a temporary option is because you mentioned that the original problem was mitigated when the main downpipe was enlarged, and that the internal leak is now in-between the white pipe and the step, which could indicate that the capacity of the gutter is ok with the current loading even during heavy rain and that it is the turbulence causing water to penetrate under the roof in one localised area. It is still risky though for the reasons stated above.

In the long term that second roof must not discharge into that gutter at all. Tim is being polite by only calling the current design shocking...

 

[Nesian]

Thanks for the help people.

There is only the one house under all that roof and there are only the two downpipes handling all that water. One is the down pipe that you see in the video and there is another one at the opposite end of the house.

You can't actually punch out of through the end wall because there is a chimney there. I think that might be why they just put the white pipe there to help offset everything.

I understand that we should try to avoid any extra water going into that gutter but for the moment there is not other option.

Unfortunately my father is a retired pensioner and can't financially afford to get a pro in to do the job. Just to get the down pipe enlarged and and the associated gutter with the down pipe (about 2.5 meters) cost just over $1000 and that was about 5 months ago, I swear you have to sell a kidney to be able to afford a tradesman now a days...

Thanks, If you guys come over the rugby world cup and end up down the very bottom of the country I'll have a beer waiting for you............and a hanky for when your team loses in the cup....

 

[Nige F]

Sorry to hear the $ huge amount for the new pipe and section of gutter - Unfortunately I was going to suggest that an outlet shaped like a funnel with rounded edge will deal with a greater flow of water - saw it done on a guttering system here in UK some years ago - But of course it`s done now Shame is that you posted after the work was done

 

[Nesian]

We thought the work we were getting done to my dads house was going to fix the problem altogether so we were gutted when we saw water dripping through the new ceiling earlier this week.

I wish I had thought of coming to a place like this before we got the work done because I have a far better idea of what we could have done and what the problem actually is (thanks to the posters).

Sorry to hear the $ huge amount for the new pipe and section of gutter - Unfortunately I was going to suggest that an outlet shaped like a funnel with rounded edge will deal with a greater flow of water - saw it done on a guttering system here in UK some years ago - But of course it`s done now Shame is that you posted after the work was done