Roofing techniques question

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Hi All

My girlfriend has had her roof replaced. The old roof was rosemary tile, about 6 inch by 12 inch in size (from what I remember). The new roof is in some kind of flat concrete manufactured by Redland, I guess DuoPlain http://www.monier.co.uk/products/product-catalogue/productcategory/plain-tile-range.html but considerably larger than the old rosemary tiles (at least 50% bigger in both dimensions).
The house is one half of a semi, so the new tiles have had to be mated up to the old rosemary tiles on the other side of the house. Additionally, the non-functioning chimney had work done to it. The quote sheet said a vented cap would be installed which I presumed would look something like this:
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Currently, I can't actually see anything on the chimney stack at all, so I'm wondering if it has been concreted over. This may be relevant to a question I'll ask later.


I'm curious about how the two roofs with differing tile should be joined. Having climbed the scaffold to have a look at what has been done on this particular roof, it seems the two mating surfaces have been butted together reasonably closely and then a thick bead of some kind of silicone laid that predominantly touches the sky facing side of the rosemary tile, and the vertical side of the concrete tile (the concrete tiles are much thicker than the rosemary they butt up to)
Not all the concrete tiles seem cut, so some of the mating surfaces are created from the overlapping parts of the tile, giving a smaller area for the silicone to bond to and in some cases, nothing to bond to. I drew a picture:


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On the left, the tiles without silicone, redland in red, rosemary in brown. On the right, the bead of silicone runs up, but is not continuously mating between both surfaces.

Question: is this an acceptable way of mating two different tiles? What stops water ingress? I cannot see any form of guttering inside the loft underneath the join..

On the underside, the felting looks like some cross between a J cloth and a teabag; white side and black side and millions of little squares sticking the two sides together as if a hot roller has melted the two membranes together at certain pinpoints. I've looked on google images for ages, but can't find anything in good enough detail to know whetehr it's breathable or non-breathable. I ask because there's quite a bit of condensation on the inside of this membrane, on the shaded side of the house. The sunny side was fine, dry, no problems. This also refers to the original query I had over what happened to the chimney: once upon a time, it was an open pot, broken to one side (letting in water at the top and round the base plate) but now nothing is evident on top of the chimney stack. If this has been sealed up completely will it be causing condensation problems?

Given that I have access to the roof and a digital camera, is there anything I can check and/or photograph for you guys to have a look at to be able to say whether this job is likely to give problems? We're currently discussing with the builder what to do about the bathroom ceiling skim work being broken during the works (seems that flex in the roof truss members as they walked ont he roof, has damaged the ceiling that is affixed to the other side of the truss.. The bathroon ceiling follows the roof line on one side of the room

Thanks in advance for reading a long boring post ;)
 
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The bond should really be either a third round hip bedded at the bond (with soakers to the plain tiles)or a bonding gutter (GRP or lead). Just having a line of mastic at the bond if that's what has been done isn't going to be successful in the long (and probably short) term

A photo rather than a sketch would be useful

From your description of the felt it sounds like it's a breather felt such as Permo Forte or Tyvek
 
terracotta vent terminal or elephants foot as we call them is really what should be on your obsolete chimney stack.
remembering also to vent the fireplace if you have sealed it over.

the way your contractors have abutted the two roofs is completely unacceptable as previously stated.
 
If you have two different tiles meeting together you should have a bonding gutter in between then (underneath)and normally a mortar bond for each set of tiles, they should touch or a small valley should be visible between them.
Hope this helps
Dave
 
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In that case, I'm maybe not 100% happy with the join. I can't see any obvious water gulley underneath the join, but I'll have a closer look over the weekend. I'm also reasonably sure the quote included replacing the chimney pot witha vented cap, but here it seems to have been cemented over completely. Maybe I'll need some better ventilation.. Will climb into the loft and see if there is any draught near the eaves. Any comments on the pics below would be welcome.. I'm also thinking the guttering will be inadequate for the roof size, and the flat roof above the bay has leaked before.. i'm not really happy about the water drain provisions here at all and maybe I should be upgrading the guttering while the scaffold is still there. Comments?



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Showing the kind of felt used:

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All pics available in higher quality if needed. Could you guys cast your eye over and offer any possible snags I should have rectified - is the flashing round the chimeny OK, is the capping like that OK if the roof is vented elsewhere (remember the condensation note)? Is it ok to just dump the water from all the roof plus next door's gutter onto a flat roof (which may slope slightly the wrong way - didnt check but seems to fall toward house rather than away) that is served by a crappy gutter? Some parts jsut don't look finished (like having a big black tongue of a drip-mold sticking out above the bay; should I be asking for more work to be done or any tidying up?

Thanks in advance
 
hi, a few points will need to be addressed.

1. chimneyhead needs to be fitted with a vent of some description.

2. hard to tell from pics but looks as though the verges havent been done properly, verge closers, wet verge, verge strip to finish verges looks as though the tiles are just bedded down and left overhanging.

3. was there a gutter above the flat roof before retiling ? either way you will need a gutter.
personally when renewing a roof we generally renew the gutters.
at the moment you have half round cast iron gutters, i personally would renew them all with p.v.c deepflow gutters.

4. tiles cant be left abutted like that roofer should fit concealed lead gutter,
or similar water channel. roof splitter.

5. the lead aprons at the front of the chimney looks ok, but i cant see what he has done up the sides....looks dodgy though is that silicone i can see ?.
 
oops just had a closer look at pics, existing gutters are plastic o.g.
why dont you renew them the same as neighbours.

i would think twice about getting the same contractors to do the gutters.
 
still finding anomalies, if you stand on the scaffold facing the little flat roof and look to your left where the roof stops and changes to a different pitch they have butted the tile against the wall, there should be a concealed lead gutter beneath this tile, i suspect there is not. i wouldnt part with a penny until all of these points were put right.
good luck.
 
The pics can all be clicked to get a magnified version (hope you have broadband)

hi, a few points will need to be addressed.

1. chimneyhead needs to be fitted with a vent of some description.
I'm nigh on positive that fitting of a vented cap was part of the original quote. I'll see if I can find the quote. Reference toi the condensation in the loft, I presume that this sealed chimney really won't be helping? The other concern is that there is condensation currently, but the house isnt actually being used on the top floor (it's split into 2 flats, upstairs and downstairs) at the moment. When it is in use, the air will probably be a lot more humid, so the condensation may get worse

2. hard to tell from pics but looks as though the verges havent been done properly, verge closers, wet verge, verge strip to finish verges looks as though the tiles are just bedded down and left overhanging.
I will take a proper picture of the verges today

3. was there a gutter above the flat roof before retiling ? either way you will need a gutter.
personally when renewing a roof we generally renew the gutters.
at the moment you have half round cast iron gutters, i personally would renew them all with p.v.c deepflow gutters.
Not certain of before, but as noted, the roof has leaked here in past years. It is actually possible to grasp the flat roof on the left hand side of the bay window and lift it up as though it were a toy chest lid or something. This may also need addressing

4. tiles cant be left abutted like that roofer should fit concealed lead gutter,
or similar water channel. roof splitter.
Do you refer to this picture? How would the gutter run? Horizontally or with the line of the roof?
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5. the lead aprons at the front of the chimney looks ok, but i cant see what he has done up the sides....looks dodgy though is that silicone i can see ?.
I'll see if I can climb the roof again and take some more pictures.. It's fairly hammering down with rain today though


Any comment on the silicone-method of joining the new roof to the old one next door? I'll try to lift some of the tiles to see if there is a gutter above the wall cavity, under the tile joins when I go..
 
i would think twice about getting the same contractors to do the gutters.

I'm reasonably confident that I could make an acceptable job with some sound advice; added to that we have two builders in the family I can call upon.. So I think I may well do that. I can't imagine the neighbours are overjoyed with the finish of this particular aspect either.. I know I wouldn't be.
 
still finding anomalies, if you stand on the scaffold facing the little flat roof and look to your left where the roof stops and changes to a different pitch they have butted the tile against the wall, there should be a concealed lead gutter beneath this tile, i suspect there is not.

Does this refer to your point 4 above? I'll lift it and take a look. Thanks for all the time thus far.
 
The whole thing looks like a lash up, and the flat roof is fubar.
 
Some more pictures: Didnt succeed in lifting many tiles to see if there were gutters underneath; the said tiles were pretty firmly fixed with cement or were too far off-balance point on the edge of the scaffolding for me to be able to pull them up.. As before, click on the pic for a magnified version.

Apologies for the slightly weird colours; it was getting dark and the camera was insisting on flash

Showing the verges:

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Showing the eave near the cast iron gutter section
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Looking along the eave above the cast iron gutter:

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Without camera flash:

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Looking down at chimney joining, back-of-house side of the ridge tile:

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Chimney join, looking horizontally from back to house toward front of house:

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Chimney join, looking horizontally from front of house toward back of house:

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Front-of-house chimney flashing:

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Back-of-house chimney flashing:

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Lifting the drip-sheet where the steep roof and the shallow roof run side by side:

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(the white stuff in the 9-oclock position is expanding foam)


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Lifting the drip sheet where the new roof joins the neighbour's old roof, looking for a hidden gutter:

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Thanks in advance for any pointers or other things we should mention need finishing or altering
 
yup, thats the proper way to join your new roof to neighbours, sheet lead dressed over wooden bottles concealed gutters, lead upstand....etc.
labour intensive and expensive.
another way of doing it is to buy ready made bonding gutter made of fibreglass easily fitted and a lot less expensive.

your lack of chimney ventilation will not be causing the condensation in your roof space. you should get your roof completed to an acceptable standard, gutters, leadwork, proper verges get your attic re-insulated if the old glasswool has been wet.
get tile vents or soffit vents installed, i think you will find your condensation problem will be no more.

your flat roof needs replaced as well, best doing this while scaffolds still up.

i am trying to advise you in laymans terms by not using technical terminology. i also try to post any advice constructively to help in any way i can. anyone in the trade know its a very shoddy job and it was not a competent person who carried out the renewal of your roof.

i would not pay for this job......

1. have the tiles been laid properly....enough cover, nailed or clipped?

2. overlapping new tiles onto an existing roof is completely unacceptable
and will have to be stripped back out and done properly with the appropriate guttering/bonding installed, and the tiles meeting the new roof junction mechanicaly fixed into position.

3. verge tiles are just left hanging over the edges and pointed up.....they need to be stripped back out and proper verge detail installed, all verge tiles should be nailed and clipped...you would be able to see the clips at the bottom of tiles.

if you google marley, redland, and many more roofing supply websites you will get a better idea of what i am saying.
 

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