NCC - Roof Valley - Does this comply?

H A W U · Nov 12, 2023 12:12 am

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Hello everyone. Does the valley in above pictures comply with the NCC? From the looks of it, they've used some really wide valley gutter and screwed the ridge cap directly onto the valley. Not to mention there is a lot of buckling / warping of both ridge cap and the valley gutter.

Not sure why they didn't have colorbond sheet, there are 3 valleys that are like this. We have a building inspector so we will enquire with him, but I also wanted to check in with anyone familiar with NCC here.

Looking at the NCC, typical valley gutter should look like this?
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Any expertise much appreciated.

Thank you!

H A W U · Nov 13, 2023 10:02 am

15mm upstand requirement at edge of valley looks to be added in 2022 NCC?

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building-expert · Nov 13, 2023 10:44 am

can you post roof plan?

H A W U · Nov 13, 2023 10:47 am

building-expert

can you post roof plan?

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Thank you! As I understand,this was done with very narrow roof sheet section but I thought this is now updated in NCC 2022 (I.e. requires upstand so cannot be done).

it's about 500mm wide section if it helps!

Ardo · Nov 13, 2023 1:03 pm

You really have nothing for the water running down the corrugated sheets to oppose it from running under the Ridge capping.
Not sure if it's standard on valleys, but my valley flashing were over bent past 90 degrees.

H A W U · Nov 13, 2023 1:17 pm

Ardo

You really have nothing for the water running down the corrugated sheets to oppose it from running under the Ridge capping.

Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Ah yes. Like this is what you mean right?

Ardo · Nov 13, 2023 5:36 pm

Yes thats what I am thinking. The upturn under the sheet on the valley piece directs this flow down the valley.
As I miss edited the wrong post..
Not sure if its standard, but my valley flashing was over bent past 90 degrees.

H A W U · Nov 13, 2023 5:38 pm

Ardo

Yes thats what I am thinking. The upturn under the sheet on the valley piece directs this flow down the valley.

Yes, the new requirement for the upturn was added in the NCC update in 2022 for this reason supposedly. With the driving wind, they were finding situations where you still get the water into the roof from the valley.

building-expert · Nov 14, 2023 3:07 pm

The photos show lack of workmanship and aesthetic appearance, and the roof does not follow roof plan in breach of builders warranties.
Yes its defective.

slothicious · Nov 14, 2023 3:08 pm

building-expert

The photos show lack of workmanship and aesthetic appearance, and the roof does not follow roof plan in breach of builders warranties.
Yes its defective.

G'day, could you please help clarify which part doesn't follow the roof plan?

Ardo · Nov 14, 2023 5:35 pm

Perhaps the little lines under the highlighted bit that identify it as being corrugated to the valley?

building-expert · Nov 14, 2023 6:01 pm

Ardo

Perhaps the little lines under the highlighted bit that identify it as being corrugated to the valley?

Yes, correct Ardo.
Would anyone in their right mind accept the roof as built when it is drawn as corrugated to the valley?

slothicious · Nov 14, 2023 6:08 pm

building-expert

Ardo

Perhaps the little lines under the highlighted bit that identify it as being corrugated to the valley?

Yes, correct Ardo.
Would anyone in their right mind accept the roof as built when it is drawn as corrugated to the valley?

thanks guys! yes this is how I've exactly raised it with the builder. still awaiting response.