I'm trying to read up on this summer's big construction project.
I'm planning to build a porch for our caravan.
The dimensions will be 5.70x2.60m.
The roof will have a slope of about 10cm/m.
If you look at the roof construction from the inside, I was thinking:
1. Roof panel (Wood panel)
2. Vapor barrier (Plastic)
3. Insulation
4. Air gap (Rafters that are 120 and insulation 95)
5. Sheathing
Now the question comes, do you have to have first underlay felt and then roofing felt, or can you skip the underlay felt? If not, what is the benefit of underlay felt?
Lastly, roof sheet metal.
What do you think?
