Flat roof

Cliddy09

ThisIsWeird said:

Cliddy09 said:

ThisIsWeird said:

Markmywords said:

how do you add a slope to a flat roof without ripping the whole thing up ?

It was all ripped up, right down to the rafters/joists.
Possibly the slope couldn't be increased as much as desired due to some restriction on the house - as with our extension, which has french doors on the upper level which set that upper slope point. 
An insulation-conforming roof is thicker than you expect, so I'm guessing that could the issue. Our roof just drains, but some puddling forms behind the sky lanterns - not really a problem.
Waiting for the OP to explain. It really comes down to how much puddling there is - is there an actual dip in the roof, which would be unacceptable. They sound like a pro outfit, so to have skimped on the slope would have been bizarre.

I believe they "simply" left off the lengths of angled strips of wood that have to be placed immediately above the rafters to created the slope. There's a proper term for that, but can't remember.  They had them in all their equipment but obviously they weren't angled sufficiently.

'Furring' strips, I believe.
There is an external cill visible is the second pic - doesn't that limit the roof height at that point?
Our roof insulation type needed changing to the less-preferred type, and internal ceiling slightly lowered in order to get the min slope under our cill. I'd have preferred more slope, but it's fine - and supposedly warranted for 20 years (it was GRP Flexitec'd)

Yes I must admit that photo is confusing. It was taken out of a very limited space upstairs window.

But rest assured, above the flat roof line there is plenty of space. It's measured in feet not inches.

The problem is definitely related to the gradient they provided. They virtually admitted it by blaming the original build.

My problem is that they are not going to give in without a significant fight. As ripping off the whole roof again is not going to be taken lightly.
Do I want the fight and the upheaval..... no not particularly.

I was after a miracle solution or perhaps get some reassurance the felt wil be up to the job over the coming years.

ThisIsWeird

Cliddy09 said:

Yes I must admit that photo is confusing. It was taken out of a very limited space upstairs window.
But rest assured, above the flat roof line there is plenty of space. It's measured in feet not inches.
The problem is definitely related to the gradient they provided. They virtually admitted it by blaming the original build.
My problem is that they are not going to give in without a significant fight. As ripping off the whole roof again is not going to be taken lightly.
Do I want the fight and the upheaval..... no not particularly.
I was after a miracle solution or perhaps get some reassurance the felt wil be up to the job over the coming years.

I have to say, I would be disappointed and frustrated too. That's a 'pro' roofing outfit, and ensuring there's a decent slope in the roof is both fundamental, and should be standard - imo. I mean, why on earth would they not?! They've replaced everything else, so adding this would have been a minor detail, surely?

And, it really isn't for the customer/layperson to suggest or request this - it's for the 'pro' to do so.

That's all I can say, tho' - I have really no idea how this would be considered or handled by an independent arbitrator. It's one of these really awkward issues, a bit like a poorly-laid patio - to sort it would involve almost as much work as the original job, so it could be considered 'unreasonable' to have to do this...

No idea what to suggest - perhaps a 'watertight' warranty for, say, 15 years?

Any roofers on here with an opinion?

Since you know there's an 'issue' here, it makes you look more closely at the actual standard of the rest of the work. I need to emphasise that I don't know, but are the felt overlaps pretty slim? And is that a bulge in the felt, left-foreground?

ROOFERS?!

stuart45

You really need an independent expert on site to give a proper assessment.
Rule of thumb for ponding in the trade is that it should be no more than 1/8inch, and drain away or evaporate within 48 hours. Unless the joists are perfectly straight and all lined up perfectly there will always be a few areas that can retain a bit of moisture. 
When doing the joists it always best to have the crown on top. I always prefer to have the firring pieces cut for the maximum fall possible. 

Cliddy09

ThisIsWeird said:

Cliddy09 said:

Yes I must admit that photo is confusing. It was taken out of a very limited space upstairs window.
But rest assured, above the flat roof line there is plenty of space. It's measured in feet not inches.
The problem is definitely related to the gradient they provided. They virtually admitted it by blaming the original build.
My problem is that they are not going to give in without a significant fight. As ripping off the whole roof again is not going to be taken lightly.
Do I want the fight and the upheaval..... no not particularly.
I was after a miracle solution or perhaps get some reassurance the felt wil be up to the job over the coming years.

I have to say, I would be disappointed and frustrated too. That's a 'pro' roofing outfit, and ensuring there's a decent slope in the roof is both fundamental, and should be standard - imo. I mean, why on earth would they not?! They've replaced everything else, so adding this would have been a minor detail, surely?

And, it really isn't for the customer/layperson to suggest or request this - it's for the 'pro' to do so.

That's all I can say, tho' - I have really no idea how this would be considered or handled by an independent arbitrator. It's one of these really awkward issues, a bit like a poorly-laid patio - to sort it would involve almost as much work as the original job, so it could be considered 'unreasonable' to have to do this...

No idea what to suggest - perhaps a 'watertight' warranty for, say, 15 years?

Any roofers on here with an opinion?

Since you know there's an 'issue' here, it makes you look more closely at the actual standard of the rest of the work. I need to emphasise that I don't know, but are the felt overlaps pretty slim? And is that a bulge in the felt, left-foreground?

ROOFERS?!

Yes, that's a bulge! I must admit it seemed minor in context.  The other detail that continues to confuse me, is why is the puddle red ?

Cliddy09

stuart45 said:

You really need an independent expert on site to give a proper assessment.
Rule of thumb for ponding in the trade is that it should be no more than 1/8inch, and drain away or evaporate within 48 hours. Unless the joists are perfectly straight and all lined up perfectly there will always be a few areas that can retain a bit of moisture. 
When doing the joists it always best to have the crown on top. I always prefer to have the firring pieces cut for the maximum fall possible. 

Thanks for all this. Do you just happen to know why the puddle is red. It's not an optical illusion and hasn't gone away over time.

Cliddy09

stuart45 said:

You really need an independent expert on site to give a proper assessment.
Rule of thumb for ponding in the trade is that it should be no more than 1/8inch, and drain away or evaporate within 48 hours. Unless the joists are perfectly straight and all lined up perfectly there will always be a few areas that can retain a bit of moisture. 
When doing the joists it always best to have the crown on top. I always prefer to have the firring pieces cut for the maximum fall possible. 

Another point is that the whole roof doesn't drain right to left. It drains top half towards the centre and bottom half towards the centre. And from there drains collectively to the left to the gutter. Or at least that's what it was designed to do. What it's actually doing is collecting at that point and not draining away.

stuart45

Cliddy09 said:

stuart45 said:

You really need an independent expert on site to give a proper assessment.
Rule of thumb for ponding in the trade is that it should be no more than 1/8inch, and drain away or evaporate within 48 hours. Unless the joists are perfectly straight and all lined up perfectly there will always be a few areas that can retain a bit of moisture. 
When doing the joists it always best to have the crown on top. I always prefer to have the firring pieces cut for the maximum fall possible. 

Thanks for all this. Do you just happen to know why the puddle is red. It's not an optical illusion and hasn't gone away over time.

Could be brick dust where they've cut into the wall for the flashing.

Cliddy09

stuart45 said:

Cliddy09 said:

stuart45 said:

You really need an independent expert on site to give a proper assessment.
Rule of thumb for ponding in the trade is that it should be no more than 1/8inch, and drain away or evaporate within 48 hours. Unless the joists are perfectly straight and all lined up perfectly there will always be a few areas that can retain a bit of moisture. 
When doing the joists it always best to have the crown on top. I always prefer to have the firring pieces cut for the maximum fall possible. 

Thanks for all this. Do you just happen to know why the puddle is red. It's not an optical illusion and hasn't gone away over time.

Could be brick dust where they've cut into the wall for the flashing.

Thanks, that's a very good suggestion. Also explains why it hasn't disappeared over time.