Very damp in the loft..

[robwizard]

Hi. I live in a C. 1900 end terrace which has various small problems but is, for the most part, quite sound. Earlier this year we noticed condensation on the landing between the bedroom and bathroom, presumably down the showering etc. Started using a dehumidifier whenever we use and it seems to have sorted that out. Great.

Noticed a damp patch on the ceiling again.. checked in the loft and the insulation is soaking! Basically like a giant sponge sitting there leaking away I'm not 100% sure what is causing it.. but the timbers around the apex are mouldy and damp so I'm guessing it could be a leak. Will be getting a roofer out asap to check it.

Whilst musing over the issue I started reading some stuff on here which made me think that the insulation in there is not great. I'm thinking if I can get the roof sorted then what else can I do to reduce damp?

First thing will be getting an exactor fitted in the bathroom. I would like to board the loft out to be use the space for easier storage. Would it be foolish to remove the existing insulation and start fresh with something more modern? Is a vapour control barrier necessary and can this be retrofitted or does it need to go between the plasterboard and joists in the ceiling below? If so would I lay the vapour barrier in between and over the joists, insulate on top, batten the joists and then board? Will 2x1 battens provide a sufficient airgap? I'm 99% sure the existing insulation is rammed into the corners of the roof and stopping any airflow so will be clawing that out tomorrow first thing. I will also upload some pictures as I go..

Thanks!

 

[chappers]

sounds very much like a leak, can you post a picture of the roof, both sides of the ridge.
if the loft has sufficient ventilation a VCL should be totally unnecessary.
No air gap will help if it isn't ventilated, but as said a VCL shouldn't be needed.

 

[JohnD]

You mention steam from an unventilated shower.

Are there holes in the ceiling, for example round dowlighters?

 

[robwizard]

Yeah @JohnD their are round downlighters in the bathroom ceiling, also I think that possibly some pipes and holes etc going into the loft from the airing cupboard where the boiler is located.

I also have a feeling the roof is leaking @chappers .I have taken some photos earlier so I will try and figure out how to attach them.

 

[robwizard]

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• robwizard
• 18 Jan 2017

Right hand side mould

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• robwizard
• 18 Jan 2017

Right hand side full view

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• robwizard
• 18 Jan 2017

Left hand side

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• robwizard
• 18 Jan 2017

Right hand side, worst damp area

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• robwizard
• 18 Jan 2017

Rip in felt again

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• robwizard
• 18 Jan 2017

Soaking wet insulation

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• robwizard
• 18 Jan 2017

Soaking wet insulation

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• robwizard
• 18 Jan 2017

Shattered slate and rip in felt?

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• robwizard
• 18 Jan 2017

Shattered slate and rip in felt?

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• robwizard
• 18 Jan 2017

Loose flap of felt

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• robwizard
• 18 Jan 2017

Right hand side against the dividing wall

 

[robwizard]

Also, other things of note. The damp seems worse on the right hand side when looking at it, which is also the side closer the to bathroom. (Although the house is quite long so the bathroom ceiling is still a good ten-fifteen feet from this point). Another thing is that it's almost directly above the loft hatch, which fits terribly, is unsealed and also totally insulated.. can't be helping right?

I read somewhere about fitting lap vents to start the air circulating again, worth trying?

Thanks again.

 

[robwizard]

So I just checked the insulation. It's very uneven, seemingly much thicker towards the edges of the loft? It isn't stuffed right up to the soffits though, as I ha initially suspected. The soffits have no ventilation in them, is this something that ought to be addressed? Fitting vents every few feet or so perhaps?

Cheers.

 

[JohnD]

yes, it does look like you have some roof leaks, so ask around for a recommended local roofer (paid websites are not a good source of independent recommendation). But hopefully it will not rain every day. However the holes in the ceiling and round the hatch will let water into the loft every day.

Every time you take a bath or shower, boil a kettle, breathe, or hang a wet towel over a radiator, you are adding water vapour to your house. It is lighter than air (hence clouds) so it will rise up until either it escapes, or it finds a cold surface to condense on. You can fix this yourself at low cost.

You can reduce the water load with a bathroom extractor and a tumble-drier or washing line, and you also need to prevent water rising up through the holes. Expanding foam can do it, but is messy and difficult until you get the hang of it. A pink fire-resistant grade is available.

If you like downlighters, you can make a fabricate a box or hood to go round them. You can buy readymade smoke or insulation hoods, or you can make a box very easily out of plasterboard (which is also fire resistant). When you change to LED lamps they generate very little heat. Even better, you can buy a different sort of lamp and fill the holes up.

Have a look at door draughtstrip for the hatch.

If your soffits are wooden boards, and not rotten, you can drill plenty of holes in them with a biggish spade bit, but fit fine steel mesh to keep birds out. But old roofs usually have plenty of draughts in them, if you can just reduce the water content.

 

[robwizard]

I will set to getting a roofer out asap! And try and get a look at the soffits over the weekend, from what I could see from the inside they seemed pretty solid but to be fair I couldn't really 'see' as much as I was poking at them with a bit of plastic piping..

A part of me wants to drag all the gross, soggy old insulation out and make a neater job with newer, perhaps superior material? Am I just inviting a whole world of itchy, expensive, unnecessary pain upon myself?

Thanks again!

 

[chappers]

probably a waste of effort,the insulation will dry out and function fine, some extra ventilation never goes amiss.
Looks like you have problems with the back flashing on the chimney. doubt you will be able to take pictures of that but any chance of some of the general condition of the roof from the outside

 

[robwizard]

I will try and get some yeah. It's funny you should mention the chimney flashing, basically the end of the ridge is like a hipped end if that makes sense? Kind of pyramid-esque? Pictures would help.. But yeah, when I had a chimney liner fitted I could see that a piece of flashing on the forward chimney was loose and asked the stove fitter to wedge it back in, which he did. This then seemed to remedy a damp patch that kept appearing on the chimney breast lower down. The other chimney is on the other side of the pyramid apex, so can't see it at all. It's also the same side which appears to be more damp in the above photographs.

 

[vinn]

OP,
On the RH stack, perhaps both stacks, you seem to have a leaking lead back gutter and sodden, maybe beginning to rot, back gutter boards - ie the boards that support the lead back gutter.
There's something odd about how the felt has been arranged around the RH chimney stack esp above the back gutter.
You will probably have hip tiles very close to the back gutters.

If the apron cover flashing needed wedging in then its possible that any and all the chased-in flashing needs re-securing, and perhaps re-arranging?

Any difficulties at the eaves should be investigated by the "roofer" by lifting eaves tiles, and seeing whats happening below them - your felt should project over the gutter by 30mm to 50mm.

Whoever goes on your roof should be asked to take pics of what is existing around the stacks and on top of them and at the eaves.

 

[swebb99]

I had something similar in the house I recently bought (1930s). After heavy rain i noticed a bit of damn and bubbling on the bedroom ceiling. I went in the loft and noticed the wooden board near the top of chimney brickwork looked a little damn and the brickwork was a touch damn. I was getting a roofer round anyway to take a look at the baywindow covering. He looked around the chimney and found the mortar was coming loose and in area's was breaking off, one of the tiles had slipped slightly and various other fairly minor issues. He thought when it rained heavy it was usually ok however if the wind was in a certain direction the rain was hitting the side of the chimney (and soaking in somewhat) and also bouncing off back on to the tiles and going under the one that had slipped. He sorted the mortar, replaced the tile plus one other and no problems since.

Actually I say no problems, I have since floored out the loft (100MM under boards) and laid 270M space blanket on top and noticed a few spots where the blanket seems damp, still not sure if it is a leak or the moisture in the air is condensing on cold spots on the surface of the space blanket. I had no damp spots on the wood before I laid the space blankets.

 

[robwizard]

Just had the roofer out (used the guy before and he did a decent job sorting out the mess someone else had made) and he reckons that a few slates need replacing and that the loft has nowhere near enough ventilation. The biggest revelation however is that both chimney stacks have bastardized flashings made up of lead, morter and bitumen! He pointed out, whilst in the loft, an area around the chimney stack where you can actually see straight up the brickwork and see daylight. So yeah, that's not great.

He suggested that the job will comprise getting to the stack, removing the broken and ill suited slates, inspecting the leadwork and replacing where needed, then reslating correctly. Oddly enough quite similar to the other work he did on the other roof, which was seemingly a success. For the work he quoted £340 if the existing lead aprons can be re positioned and reused, and somewhere around £600 if he has to buy and fit new leadwork. He was also very happy to take hundreds of pictures along the way to satisfy my curiosity.

I thought that seemed reasonable enough? He reckons it's a days work.

Would be interested to hear thoughts on this conclusion and price?

 

[vinn]

How come he didn't take pics on this trip up the roof?

In my #12 post above there's still a number of unanswered questions that would have been easy to answer with the "roofer" up on the roof?

I was under the impression that you had enlarged your original question to the front and rear stacks? How many stacks did the "roofer" investigate?