Dry Valleys - prone to blocking?

[C08]

Are the dry valleys, the type with a W shape often in galvanized steel prone to blocking with leaves and other debris. I ask this as the gap between the tiles looks quite narrow on this system on local houses and perhaps more prone to blockage than traditional wider leaded valleys? Pondering on a new roof and the upside and downside of dry gullies, valleys, ridge tiles, hip tiles gable end verge tiles. The dry systems look more expensive on parts but presumably less labour than cemented tiles and valleys? We do have a substantial leaf deposit and moss growth on our roof!

 

[Mr Googler]

I’m afraid the roof of my BOAT is fibreglass so can’t help!

 

[BruceK]

I’m afraid the roof of my BOAT is fibreglass so can’t help!

Another gloater. Mine's canvas but if dry valleys will stop gull sh1te sticking to it sign me up for a dozen.

 

[maverickofpoole]

OP dry valleys can and do become blocked. To clean them out the roof tiles would need to be removed.
The same issue applies to secret gutters & flashings (Lead). Easy to do (apart from maybe access) but still a ball ache if you have suffered ingress of water due to a blockage

 

[MrB]

OP dry valleys can and do become blocked. To clean them out the roof tiles would need to be removed. Noop, You do not have to remove tiles.
The same issue applies to secret gutters & flashings (Lead). Easy to do (apart from maybe access) but still a ball ache if you have suffered ingress of water due to a blockage

Just treat it as you would your normal guttering on your house/conservatory/shed and scoop out the leaves.

There are companies now with long reach hoovers that will clean the gutters out without access issues.

I'm a builder so not guessing.

 

[BruceK]

I'm a builder so not guessing.

Well, isn't that refreshing

 

[MrB]

Are the dry valleys, the type with a W shape often in galvanized steel prone to blocking with leaves and other debris. I ask this as the gap between the tiles looks quite narrow on this system on local houses and perhaps more prone to blockage than traditional wider leaded valleys? Pondering on a new roof and the upside and downside of dry gullies, valleys, ridge tiles, hip tiles gable end verge tiles. The dry systems look more expensive on parts but presumably less labour than cemented tiles and valleys? We do have a substantial leaf deposit and moss growth on our roof!

Go dry every time unless you are in a listed building. I have never seen a galvanised steel valley. A valley on a hipped roof will always be the same width-ish on a normal type house regardless of the material to create it.

 

[MrB]

Well, isn't that refreshing

Not as refreshing as raiding (and emptying) your funbox

 

[BruceK]

you valley boys keep your hands off my stash.

 

[maverickofpoole]

On a dry fix valley yes you can scoop leaves that sit on top of the valley however you cannot scoop out rubbish and debris that falls between the tiles and gets trapped in the valley liner. Granted this takes a long time to happen but it does.

Oh and I am also in the trade

 

[C08]

OP dry valleys can and do become blocked. To clean them out the roof tiles would need to be removed.
The same issue applies to secret gutters & flashings (Lead). Easy to do (apart from maybe access) but still a ball ache if you have suffered ingress of water due to a blockage

Sorry this is in the wrong forum.
Thanks we do have a particular problem with leaves and moss. The 3 houses I have looked at seem to have about 2" width between the tiles and with the centre of the W shaped upstand in there as well and look made to block up. I think I will go traditional lead and pointed up valleys, although that system is more dependant on the skill of the roofer perhaps.
My next door neighbour who is an architect has the view that the dry systems are more foolproof and do not need the same level of skill as traditional leading etc. He said he would not recommend dry valleys where there is a big leaf fall problem and more potential for blockage as removal he says can be difficult..