Roof Underlayment Guide - What's The Best Roof Underlayment, Underlayment Types, & More 

What kind of additional years of security are you expecting when the underlayment has thousands of nail holes from shingle installation?

Stick with 30 lb felt. Synthetic is easier and faster for the roofers, but not really that much.

Malarkey recommends their UDL underlayment for tile roofs.

Synthetics are not usually used under tile. Instead, a UDL underlayment works better with the weight of tile roofs. It is also much thicker and heavier and should not flap. Since your tile roof is already installed, I don't see an easy fix.

@@slydog7131 Thank you for the advice. What is an UDF though? I may want to experiment with it on another roof in future.

@@johanolwage213 UDL is a rubberized asphalt underlayment, something like heavy felt but thicker with some flexibility. My understanding is that various manufacturers make this. You can find some more information by going to the Irish-sounding asphalt shingle company's website (my experience is that if I write the name then RU-vid won't post this reply) and looking at their underlayments where you can find specs. It is their recommended underlayment for tile roofs, but it can also be used for other. You might also check with a roofer that is certified with their products as they might have small samples that they show to customers. That is where I actually saw the difference between UDL and synthetics. In my market area the building supply doesn't carry it. They could order it but I would have to buy an entire pallet load, which I don't need.

Wake up? It is 8pm CET and bedtime in like 2 hours😁👍

@@fredrikjaensson7350 lol you looked so sleepy