Roofing felt vs tongue and groove roof decking

[rightnow]

Hello,

Roofing membrane or raw pine? Which is better? The reason I'm asking is because, for example, Rörvikshus uses roofing membrane while some other manufacturers use raw pine.

Found a thesis on this from 2006:
http://hj.diva-portal.org/smash/get/diva2:4162/FULLTEXT01

According to this, roofing membrane is better.

 

[Joco_]

When we replaced the roof and swapped out the oil-hardened board, we chose raw pine boards. Mainly because it felt the most solid & well-tested.

Then what is best is probably impossible to answer.

Disadvantages that have been mentioned with membrane are that it can flutter when it's windy and cause noise, but that could just as well be a myth.

 

[rightnow]

Yes, it seems that most people I've read agree that råspont is robust and well-proven.

According to a seller, there are some advantages with roof membrane since today's houses are so well-insulated that moisture can form on the underside of the råspont. The roof membrane breathes better?

 

[isolde]

Why I'm asking is because, for example, Rörvikshus has roofing felt while some other manufacturers use board sheathing.

Roofing felt naturally has higher vapor permeability, but board sheathing reinforces the entire roof structure, and most importantly - you can walk freely on the roof during various roofing tasks. In a severe storm, I rely more on board sheathing (with roofing felt on it) than on just roofing felt. House manufacturers mainly focus on the economy. They press prices to make their houses attractive to prospective customers.

 

[Joco_]

I have "solved" that by insulating on the exterior roof instead (klimatvind), which means the dew point ends up outside the construction instead.

 

[rightnow]

Roofing felt obviously has higher vapor permeability, but roof decking stiffens the entire roof structure, and most importantly - one can walk on the roof unimpeded during various roofing work. In a strong storm, I prefer to rely on roof decking (with roofing felt on), rather than just roofing felt alone. House manufacturers primarily focus on the economy. They push prices to make their houses attractive to prospective customers.

Yes, that was definitely a point with the stiffness!

 

[pelpet]

In a thread here on byggahus, the original poster has a problem with wasps that have created holes in the roofing felt, and the manufacturer does not want to compensate the original poster because it involves pests.

From that description, it sounds like roofing felt is a real risk construction.

 

[b8q]

And besides wasps, there are birds, mice, and other animals with beaks, claws, and teeth. I think I'll stick with råspont.

- sent from my mobile, via the byggahus app.

 

[rightnow]

Thank you for all the great answers!

 

[JOW]

Raw plywood for torsional rigidity and external insulation for the dew point.