Flat Roof Gutter Help

[Richini]

Good afternoon. 

 

Looking for some guidance on what to do with our flat roof gutter. The roof was recently changed to a flat roof, previously being a glazed roof. The current guttering is based around the previous conservatory guttering system, but having pulled the gutter off I can see the roof insulation is coming through and water is collecting in the channel behind the gutter. I'm looking for ideas on how this should be sealed and finished properly please. 

 

 

[Mr Punter]

You need a fascia to fix the gutter to and a soffit to cover the gap at the bottom.  You probably need to get rid of the white pvc fascia and see what you can fix to.  The room will only be good for storage.

[Richini]

Thanks for the reply. Would it be acceptable to deepen the timber fascia by adding another piece of timber below the existing? 

 

Theres probably 5mm between the plastic fascia and the roof lip is this enough to get a gutter and clip in to? 

[Redbeard]

Has the roof been stuffed full of insulation? If so you could end up with condensation on the underside of the roof 'deck'. What did the installers tell you?

[markc]

Is it a metal C section or I section beam above the door? If so it will be cold and form condensation itself regardless of ventilation above the insulation.

Do you know the make up of the roof? Hard to envisage what they have done

[Iceverge]

More pics please. Before during and after. 

 

Do you have any list of works the builders undertook? 

 

Like @Redbeard says it could be a recipe for condensation and rot if not done correctly. 

 

[Mr Punter]

2 hours ago, Richini said:

Theres probably 5mm between the plastic fascia and the roof lip is this enough to get a gutter and clip in to? 

 

No, this will not work.  The drip from the roof should be in the centre of the gutter.  Often you need to put a timber like 4 x 2 on the outside before fitting the metal trim and membrane, but that didn't happen so you will need to get rid of the plastic fascia and fit a timber one further back.

 

As the others have said, the insulation as it is will be a recipe for condensation and this will be more so if you use this for anything other than storage.

[Richini]

thanks for all the comments. A couple pictures attached. This is just a utility area. The main area was insulated with recticel, with the insulation roof lagging just used at the ends for some reason. 

The original glass roof was removed, but the original conservatory style gutter which connects to an alloy beam (synseal eaves gutter) was left in place. Unfortunately water is getting in behind the gutter and making its way down the inside of the patio door. First pictures shown above show the gutter removed. The alloy beam sits about 100mm back from the roof lip. I'm struggling to figure out how I can replace the guttering and make it watertight above the patio door. 

 

Thanks. 

 

 

[ETC]

The gutter is too low and falling towards the building. Raise the gutter to the underside of the flashing.

[Nickfromwales]

Can't you get the installer back? They can't have priced you for an "only slightly leaky" roof conversion?? Make this their problem and get them to do it properly.

[Redbeard]

So, we've got (?) sub-75mm rafters and some Recticel. The current gov't standards recommend a 50mm ventilation gap with sufficient vents on each side. What thickness of Recticel did they use? I fear that problems may have been built in under that nice-looking roof. (and of course its failure to run off into gutters is at least one). I agree wholeheartedly with @Nickfromwales. They need to be invited back to tell you how they will make what they have done actually work in practice. (Of course we don't know the specifics of the 'contract'. It would certainly be useful to know, for example, is there was any 'you do this and I'll do that' agreement, which could alter the facts of what we appear to see).

[Richini]

I've gone back through our paperwork. His initial quote was for grey trims turned down into existing gutter. His opinion is it wasn't part of his job and isn't interested in coming back. Admittedly a mistake on my side and didn't really consider the consequences at the time. 

 

I'm already struggling getting a roofer to come take a look at the guttering to sort out, but what's the main points they need to address?

[Iceverge]

1 hour ago, Richini said:

I've gone back through our paperwork. His initial quote was for grey trims turned down into existing gutter. His opinion is it wasn't part of his job and isn't interested in coming back. Admittedly a mistake on my side and didn't really consider the consequences at the time. 

 

I'm already struggling getting a roofer to come take a look at the guttering to sort out, but what's the main points they need to address?

I've been taking deep breaths and thinking hard about how not to say you'll need to start from scratch if you want a satisfactory job.

 

I think whoever installed is very inexperienced at best but more likely has no knowledge or interest in making you a safe and long lasting roof. By all means pursue them for compensation but I wouldn't be letting them work on my house again. 

 

Ultimately I fear you'll need to take down everything that's there and rebuild it properly at your own cost. 

 

You could bodge it to stop rain coming in but it'll be only a temporary solution. 

The main issues I can spot are. 

 

1.  Insufficient support for the roof timbers at the high side of the roof. 

2. The absence of a satisfactory airtight layer to contain internal humidity.

3. Insufficient overhangs to allow correct water shedding. 

4. Insufficient tie downs to keep the roof in place in a storm. 

5. Insufficient fixings to the lintel at the low side of the roof. 

6. An incorrectly installed and located gutter. 

7. An insulated metal lintel that will attract condensation. 

 

 

You have water ingress, almost certainly condensation issues, and I reckon a dangerous roof in the event of strong winds or heavy snow loading. 

 

 

 

Personally I would cut your losses and start fresh. 

 

 

Sorry to be the bearer of bad news. 

 

 

[Nickfromwales]

30 minutes ago, Iceverge said:

I've been taking deep breaths and thinking hard about how not to say you'll need to start from scratch if you want a satisfactory job.

 

I think whoever installed is very inexperienced at best but more likely has no knowledge or interest in making you a safe and long lasting roof. By all means pursue them for compensation but I wouldn't be letting them work on my house again. 

 

Ultimately I fear you'll need to take down everything that's there and rebuild it properly at your own cost. 

 

You could bodge it to stop rain coming in but it'll be only a temporary solution. 

The main issues I can spot are. 

 

1.  Insufficient support for the roof timbers at the high side of the roof. 

2. The absence of a satisfactory airtight layer to contain internal humidity.

3. Insufficient overhangs to allow correct water shedding. 

4. Insufficient tie downs to keep the roof in place in a storm. 

5. Insufficient fixings to the lintel at the low side of the roof. 

6. An incorrectly installed and located gutter. 

7. An insulated metal lintel that will attract condensation. 

 

 

You have water ingress, almost certainly condensation issues, and I reckon a dangerous roof in the event of strong winds or heavy snow loading. 

 

 

 

Personally I would cut your losses and start fresh. 

 

 

Sorry to be the bearer of bad news. 

 

 

I think this is about spot on tbh......  

 

I'm guessing this was a cash job and no building regs involved? If not, then you need to get your money back, or ask them to do the work to the correct standard.

[Richini]

Thanks for the information. This wasn't a particularly cheap mistake to make, so pretty disappointing the corrective work is so drastic. 

[Iceverge]

From looking at it the insulation is fitted between the rafters, AKA a hybrid roof. 

 

These are fine if done by someone who knows their business but really require an immaculate airtight layer somewhere to prevent any any condensation in the roof. It really needs to be a perfect airtight layer to be sure it's effective. 

 

From looking at the rest of the job this is unlikely to be the case and I'm very sorry that a "builder" took your hard earned cash and did a substandard job. 

 

If it was my roof I'd do the following . 

 

1 .Strip the existing roof back to the bricks, take down the parapet on the gable end. 

 

2.Install timber wall plates on top of a DPC on the brick walls. Strap them to the walls with galvanised tie downs to resist wind uplift. If possible include a strip of insulation outboards of the plates to keep them warm and not attract condensation. Add a plate on top of the "L" lintel above the door and screw it to the metal with self drilling screws. Add a layer of PIR outboard and a 10MM PVC fascia over the top to finish. 

 

3. Install insulated metal cladding straight onto the wall plates. The narrow span makes it an ideal solution and does away with the need for extra internal timbers and ceiling finishing. Appropriately foamed ( I recommend illbruck FM330) it will be completely airtight and condensation safe.

 

4. Add either a propierty gutter for insulated metal roofs or a standard UPVC one screwed to the fascia. 

 

It will cost some cash but should be cheaper than the original job. Make sure that the flashing tieing the roof onto the main house is cut into the bricks and sealed appropriately too. 

 

 

[Richini]

Thanks for the comments. I liked the idea of the insulated metal cladding just struggled to find any local installers of it.