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36 replies
28k views
36 replies
Roofing felt under sheet metal roof, how to finish?
Hello
I am building an extension with a low-pitched roof, 3 degrees, which in the fall will be covered with sheet metal.
How do you make the connection/termination to the gutter?
I guess eaves flashing isn't needed since the sheet metal solves it?
Should the roofing felt stick out a few mm while waiting for the sheet metal worker?
K
I am building an extension with a low-pitched roof, 3 degrees, which in the fall will be covered with sheet metal.
How do you make the connection/termination to the gutter?
I guess eaves flashing isn't needed since the sheet metal solves it?
Should the roofing felt stick out a few mm while waiting for the sheet metal worker?
K
Renovator
· Kalmar län
· 2 600 posts
What kind of metal is it? Standing seam roofing? Profile sheet?
I would say that if there is underlay felt, a base flashing should be installed; I can't think of any roofing where it is omitted.
Keep in mind that underlay felt/membrane has limited resistance to free exposure (check the manufacturer's instructions), so you may need to cover the felt if there is a delay before it's covered.
I would say that if there is underlay felt, a base flashing should be installed; I can't think of any roofing where it is omitted.
Keep in mind that underlay felt/membrane has limited resistance to free exposure (check the manufacturer's instructions), so you may need to cover the felt if there is a delay before it's covered.
Hi
I asked the tinsmith, skip the underlay roofing felt but use a coarse felt "2500".., was the answer.
I asked the tinsmith, skip the underlay roofing felt but use a coarse felt "2500".., was the answer.
Renovator
· Kalmar län
· 2 600 posts
What kind of metal roof is to be installed?
A bit confused by the instructions you received. Taking a paper "2500" I would interpret as underlayment YEP 2500 but then you wouldn't have underlayment...
A bit confused by the instructions you received. Taking a paper "2500" I would interpret as underlayment YEP 2500 but then you wouldn't have underlayment...
Member
· Blekinge
· 10 117 posts
I wouldn't hire that sheet metal worker who says that. Of course, there should be a roofing felt under a metal roof, regardless of type. As pointed out, the roofing felt cannot remain exposed for a long time. If you are going to cover with strips or sheets of metal that are folded, the metalworker usually places a drip edge under the edge of the roofing felt, around which the covering metal is then folded. In that case, the felt should not be glued or nailed at the eaves. You need to figure out a way to temporarily secure the felt. YAP 2200 with self-adhesive edge is a good type of felt for this purpose. I can't see that an increase in the amount of asphalt could be a solution to the problem.
Renovator
· Kalmar län
· 2 600 posts
The plate installed at the eaves during standing seam roofing is called a "språngbleck" if you want to google it. However, as far as I know, it is not sold pre-made, so the tinsmith should be responsible for preparing it for your work if such a roof is to be installed.
Everything sounds a bit strange, and I wonder if someone is misunderstanding something: you, the tinsmith, or me.
Everything sounds a bit strange, and I wonder if someone is misunderstanding something: you, the tinsmith, or me.
Member
· Blekinge
· 10 117 posts
Well, it's not a spring flashing because those are normally folded. A straight eaves flashing of the same sheet metal quality as the cover plate is needed.
Renovator
· Kalmar län
· 2 600 posts
It was according to the image below that I meant. I got something like that from the sheet metal worker before the roofing of a roof that was then covered. Were you thinking of something else?J justusandersson said:

Member
· Blekinge
· 10 117 posts
Such spring flashings I have only seen in connection with old metal roofs. If you have enough overlap, it seems to be overkill. By spring flashings, I meant those you can buy at, for example, Byggmax and which are used in connection with simple tar paper coverings. The main function of the eaves flashing is to hold the lower edge of the metal covering. I think the knowledge level among roofers varies enormously.
Renovator
· Kalmar län
· 2 600 posts
Aha, yes in my case I like over-engineered solutions and it's a roof on an old house, so I wanted such metal even before I contacted the roofer, but he also recommended it before I could suggest it. I think it seems quite sensible from a water perspective in addition to looking nice.J justusandersson said:Such flashing I've only seen in connection with old metal roofs. If you have enough overhang, it seems unnecessary. When I think of flashing, I think of those you can buy at places like Byggmax and that are used with simple felt coverings. The main function of eaves flashing is to hold the bottom edge of the metal covering. I find that the skill level of sheet metal workers varies enormously.
Member
· Blekinge
· 10 117 posts
Roof pitch and metal type also matter, but I love skilled and ambitious sheet metal workers!
Hello
I might be a little confused. "2500" came from the sheet metal worker, and his response to the question of whether I should add 2 layers was that it's not necessary, which I perhaps incorrectly interpreted as not needing underlayment paper.
Since I don't know how many weeks or months it will be without metal, I have bought the following: SEP 4100, 3 degrees, self-adhesive, 7x1m, black.
It felt like an OK compromise to lay without underlayment paper? I can of course add underlayment paper if necessary.
I have looked at a newly built veranda that resembles ours, no eaves metal and the paper ends flush with the roof boards. The metal bent down towards the gutter.
I might be a little confused. "2500" came from the sheet metal worker, and his response to the question of whether I should add 2 layers was that it's not necessary, which I perhaps incorrectly interpreted as not needing underlayment paper.
Since I don't know how many weeks or months it will be without metal, I have bought the following: SEP 4100, 3 degrees, self-adhesive, 7x1m, black.
It felt like an OK compromise to lay without underlayment paper? I can of course add underlayment paper if necessary.
I have looked at a newly built veranda that resembles ours, no eaves metal and the paper ends flush with the roof boards. The metal bent down towards the gutter.
The slope becomes about 3 degrees or about 15cm over 2.5m
K
K
Renovator
· Kalmar län
· 2 600 posts
I'm not an expert, but it sounds like you might be a bit off track. The paper you describe is a surface paper and doesn't seem like a sensible choice to have under metal. It's a surface covering that should be placed on an underlay paper, and then it's finished. I think it's becoming clearer that the roofer has said you should lay an underlay paper, and he wants the slightly sturdier quality YEP 2500. I would recommend you check the whole foundation work with the roofer again.
It still hasn't been revealed what type of metal roof is going to be laid.
It still hasn't been revealed what type of metal roof is going to be laid.


