Low pitch roof issues

[BlessedlyBrian]

Have had an outhouse in the garden rebuilt. Roof was designed to be essentially a flat roof with 10 degree single pitch with reclaimed hand made pantiles as a covering to make it look prettier with a.

Seems the builder didn't quite get it and installed it as follows:
20mm marine ply, tyvek waterproof membrane laid directly on it and then battened across for the pantiles to hang off.

Issue seems to be water building up on top of the membrane behind the batons then seeping through and also condensation patterns on the underside of the marine ply.

Have asked another builder friend and he's come up with a solution but I'm not sure about it. Take off the old roofing down to the ply, put batons running down the pitch of the roof, put an impermeable membrane down (thinking either EDPM or bituminous underfelt) then cross batons to hang the tiles off.

Any ideas or thoughts on this would be very welcome indeed. Just starting to put my materials order together.

Many thanks

Brian

 

[catlad]

That sounds a much better solution.

 

[^woody^]

You need to treat this as a flat roof and fit mineral felt to the deck (with sealed laps), then the battens running in line with the slope, then the tile battens on top.

Felt would be preferable to EPDM as the batten fixing holes will self-seal.

 

[BlessedlyBrian]

Thanks woody, thats confirmed my suspicions.

 

[jontop]

As long as you are aware that the tiles are just for show and they will not keep the rain out

 

[BlessedlyBrian]

Yep, purely decorative. Thanks

 

[Willmott85]

Hi, appreciate this is an old thread, but sounds like you had built something along the lines of what I am looking to do. An outdoor seating area with as shallow as possible roof, using clay pantiles purely for the aesthetics.

Are you able to share the final solution you went with, and whether you have had any problems since?

 

[freddiemercurystwin]

Brian hasn't posted anything since 2016, suggest you start a new thread.

 

[Willmott85]

Brian hasn't posted anything since 2016, suggest you start a new thread.

It was worth a try!

Any able to elaborate on the build up of the roof mentioned here though? A simple sketch would be great, I just don't follow the proposal.

 

[Willmott85]

You need to treat this as a flat roof and fit mineral felt to the deck (with sealed laps), then the battens running in line with the slope, then the tile battens on top.

Felt would be preferable to EPDM as the batten fixing holes will self-seal.

Hi Woody, on he off chance you are still on this forum, any chance of a bit more explanation on your proposed build up discussed above? I'm wanting to do a very similar thing to the original poster, and sounds like this would help

 

[datarebal]

We would ply , counter batten then torch on the whole lot. Then tile it as normal . Any nail holes are on the raised bits over the counter battens .

 

[Notch7]

Hi Woody, on he off chance you are still on this forum, any chance of a bit more explanation on your proposed build up discussed above? I'm wanting to do a very similar thing to the original poster, and sounds like this would help

Woody is still about, time hasn’t tempered his sarcasm

 

[^woody^]

Woody is still about, time hasn’t tempered his sarcasm

It's like a good malt, it just keeps on getting better and better with age.

 

[^woody^]

Hi Woody, on he off chance you are still on this forum, any chance of a bit more explanation on your proposed build up discussed above? I'm wanting to do a very similar thing to the original poster, and sounds like this would help

As the post below yours says, you basically treat the low pitch as a flat roof, cover it as such and that provides the weather protection. Then you batten and tile in the tile of your choice which is primarily for aesthetics, but any rain that gets past the tile is dealt with by the [flat roof] felt.

 

[Willmott85]

As the post below yours says, you basically treat the low pitch as a flat roof, cover it as such and that provides the weather protection. Then you batten and tile in the tile of your choice which is primarily for aesthetics, but any rain that gets past the tile is dealt with by the [flat roof] felt.

ok, I understand. However, can you provide a layman's explanation of the structure of the flat roof build up?