high front gutters? / other solutions and ideas please?

[marmic]

More ideas / recommendations required on gutters please!  Capacity I'm comfortable with - issues are ventilation and water overshooting gutter during heavy rainfall. And keeping it nice visually - single storey and at one elevation eaves are at eye level from adjacent higher ground.   Preference is galv finish, but anthracite grey or black will also work.  Brackets have to be fascia fixed. Standing seam roof anthracite grey at 10° with matching fascia/barge. 

 

Matching spacers for ventilation limited to plastic systems it seems. These are to maintain ventilation behind gutter for airflow into roof cavity (through FV250 vents).  Have asked BPD (Glidevale) if we don't use spacers whether they consider ventilation from above/in gutter space acceptable (personally can't see why not).  If yes may or may not run it past BCO.  If acceptable that problem solved meaning we can use galv steel gutter / similar  - but then means further increased gutter size which won't look great on a relatively small building so just moves the problem! (and jumps in cost)

 

Water overshooting gutter is my other issue so need to make sure we have sufficient projection (and no option to raise height of gutter). Obvious solution is larger gutter - but again will be visually dominating / not pretty!  There's no calculation available (extract below from article by mgma.co.uk) so have been up on roof with watering can, spirit level, and rule!

 

Osma (wavin) stormline with spacers currently seems the best option - but my 'getting soaking wet' trial tells me heavy downpours might still slightly overshoot.  Packing out further with addtional spacer not possible as that then takes rear of gutter beyond where it needs to be for standing seam roof drip detail.  This product has a slightly raised front edge - but needs to be higher. Could be the way we have to go, but would rather be 110%.  In addition to not wanting a waterfall we are off grid RWH so need to catch every drop! 

 

Anyone know please of any other high front gutter system available in UK? Avoiding super expensive bespoke options!  Or any recommendations for bespoke at sensible money?  Seems to be the obvious answer, but need to find it!

(frustratingly plenty on the market in Australia - I guess as metal roof systems been used so much more commonly than here for decades. But no time to import anything and wouldn't be cost effective or sustainable!)

 

Fingers crossed.................... 

 

 

   Different types of roof surfaces will create either more or less projection of discharge at the roof
edge; for example, water will flow faster down a standing seam metal roof than a stone tiled
roof. Currently there is no formula available that can establish the projection of water flow from
the edge of different roof pitches, heights and roofing materials to enable the installation of the
correct width of gutter.