A few weeks ago, I discovered that, in addition to the water running in the gutter (which is OK), it was also dripping on the underside of the part of the roof that extends about 30 cm above the garage. At the end of this part, there is a downpipe that I thought should catch the water... Some parts on the underside of the roof portion that sticks out are a bit "semi-soft."
When I went up to the garage, I saw the following:
A couple of things I'm considering: a) I suspect that the metal roof is too short, which probably means that not all the water can flow to the gutter; instead, some of it runs backward and down.
b) There have been previous attempts to use silicone to supposedly prevent the water from running backward.
Question 1) A roofer said that this type of metal should not be used on a garage roof like this due to the slope/load and drainage. Instead, a tar paper roof that is "welded" (?) and extends all the way to the gutter should be used. Is that correct? Should I switch to a tar paper roof? If you think the metal roof can remain, can the metal on the roof be extended so that the water runs directly into the gutter?
Question 2) On the inside of the garage, I can see that parts of the ceiling have been water-damaged, and some parts of the insulation are dark/black. In what order should I address these issues? Redo the roof? Fix the interior ceiling first? Fix everything while redoing the roof?
This is what the roof looks like when snow from the house melts down:
Even double-seamed sheet metal should work on your roof, so you don't need to have roofing felt.
Extending the sheet metal might work, but I think you risk getting water creeping back up along the sheet metal if you don't fix a good drip edge or alternatively cut the sheet metal in some clever way.
But what I have now is probably not double-seamed sheet metal (what I have is probably corrugated roofing sheet), or do you mean that it could be an alternative to felt?
What are the advantages of double-seamed sheet metal?
Yes, your metal sheet is corrugated. Double-seamed metal sheet is an alternative to felt.
Your corrugated sheet is joined so that water runs from a higher sheet to a lower one, but I think it works poorly with too low a roof pitch. A seamed sheet is instead joined on the side with a raised edge and should not be as dependent on the roof pitch.
A folded roof should have a minimum pitch of 5.7 degrees (1:10) in special cases if there are no obstacles and the sheet metal can be made in one length, it can be reduced to 3.6 degrees (1:16). So sheet metal is not a given, a well-welded pappan is a good roof.
Looks too flat for "dubbelfalsad plåt" so I wouldn't lay that, I would lay "svetsat pappan". "Svetsat pappan" means that the joints on the "pappen" are welded together with a propane torch.
This sheet is not approved for this roof pitch. Additionally, it is too short. The remaining options are to remove the sheet, install råspont or equivalent, and install a rubber asphalt sheet with a 20-30 year warranty.
Rubber asphalt mat is probably modern roofing felt?
Perhaps a somewhat silly question, but how do you usually cover the roof from the time you've removed the metal until someone has helped you with the roofing felt. Is there a special tarp?
Thinking of tearing it off myself, checking the material underneath, and then when that's fixed, ask someone to come. And even if a date is booked, there might be a small gap or it might start raining...
You shouldn't have to build some sort of tent around it, right?
