Roofer or Plasterer or both?

[butchdingle]

woody thanks for coming back to me the Dish has been up for years so not that in the last 12 - 15 months both us and the neighbour have had new soffits and gutters put up including Dry Verges? (as per the pictures)
The one in the "Rendering" image show the guttering attached to our roof, not a lot of mortar around that ? is that a possibility for my problem or are you saying this is on the wrong side of the wall for it to be causing an issue? What about an issue with the dry verges - if these have just been put on over the old mortar ones could that be causing my problem especially if there was an issue with the felt/batten beforehand that we weren't aware of.

I have a roofer coming to repoint the rear of my house and replace some broken tiles and damaged lead flashing as we have water coming in through holes in the felt and he says that the lack of mortar, issues with lead flashing and broken tiles is causing my leak at the back of the house.
He is also going to mortar the front as well

I am hoping to go in the roof space at some point today and see if i can get over to the area at the front of the house and see if i can see anything with the Cavity from the inside

 

[butchdingle]

I have been in the roof space and can't see any real issues with the Cavity wall from what i see (not an expert by any means), i can see where something has been filled in previously but not sure how new that is.
Also for info pictures of felt in area and then in general at the front? How does it generally look at the front anyway?

Also added a picture of the roof at the back of the house where it has been leaking in and the roofer is going to repoint, replace broken tiles and the lead flashing.

He also mentioned I may need to have the felt replaced and any rotten battens replaced also, so my question on this part is should i have this done at the same time or should the repointing replacing broken tiles and sorting the lead flashing solve my issue at the back?

 

[^woody^]

That damp patch is very localised, and bearing in mind that moisture does not cross a cavity unless it is bridged, that might be the actual problem - rather than the fact that water is entering the cavity which can happen without issue.

So it might be an idea, as you have thermalite blocks, is to cut out that damp rectangle with a hand saw to investigate the cavity. The cut out bit of blockwork and then be slotted back in in one piece and bonded back in place with panel adhesive. Scrape the plaster off before cutting the blockwork.

So if you can't see anything obvious, or don't want to go through the many possibilities and wait, consider that as an option.

Check if you have poly bead insulation first! Unlikely, but be prepared.

 

[butchdingle]

Hi Woody, Thanks for your response, sounds to me like you are saying my Cavity could be blocked then?
In which case as all that you are saying to me sounds a bit like gobbledegook as i cant see a damp rectangle and I am not sure what to do and wouldn't want to make it any more of a mess am i better getting a builder to come and have a look?
If it is blocked is it a big/expensive job to fix for a builder?

Not sure if there is any insulation in the cavity not had any installed whilst we have lived here and that's at least 15 years

 

[^woody^]

as i cant see a damp rectangle

The photo you posted first?

 

[butchdingle]

Woody, sorry you mean the plastered wall in the bedroom?

 

[^woody^]

That's it. The damp plaster has to come off anyway.

 

[butchdingle]

That's it. The damp plaster has to come off anyway.

Is this something that a plasterer would do if I asked them? I am awaiting a plasterer to come and quote on some other work so could ask him to quote for that at the same time.
is the wall likely to be plaster direct onto the Thermalite bricks you mentioned or plasterboard and then plaster?

Would he just be removing the plasterwork where the damaged plaster is back to the Thermalite bricks to check if there is anything in the cavity and once anything removed just replaster that area only or the whole wall?

Is all this something that realistically could be done in a day?

 

[datarebal]

There are two tiles that have been replaced on the main roof above that area.
Water could have stopped into the cavity.
Is the patch dry ?

 

[butchdingle]

Datarebal, We had Storm Christoph the day after the tiles had been replaced and the damp area on the wall extended further down the wall, I have just checked and the wall is dry but had no rain here since Saturday only some snow

 

[datarebal]

If you have fluff cavity wall fill then it's possible there's a wet bump in there. It might be possible to lift a few tiles and shine a light down the cavity from above.

Not always possible but worth a look

 

[butchdingle]

Hi Datarebal, not sure what if any insulation we have in there as we have been here over 15 years and we haven't had anything put in.

I will ask the roofer when he comes again if he wouldn't mind taking a look and see if he can see anything.

If there is something in there and every time it rains due to say a late of mortar that was letting rain water into the cavity and wetting what ever was there and then wetting the wall, if the source of the leak was sealed would this stop the wall getting damp over time once the item(s) had dried?

@^woody^ you mentioned the plasterwork would have to come off anyway and that it looked like thermalite Blocks, if the plasterer did take it back to the Blocks?? would he not have to somehow remove the blocks to see into the cavity ? If so is this something a plasterer would do? How would he then re secure the Blocks?

Should he be able to then Plaster over the Thermalite blocks or is this a question more to ask in the Plastering forum?

 

[^woody^]

So it might be an idea, as you have thermalite blocks, is to cut out that damp rectangle with a hand saw to investigate the cavity. The cut out bit of blockwork and then be slotted back in in one piece and bonded back in place with panel adhesive. Scrape the plaster off before cutting the blockwork.

Whether a plaster can or can't do this, you'll have to ask. I could do it and I can plaster (sort of ) but I'm not a plasterer. So, the point is do you need a plasterer? No, what you need is someone who can plaster, can cut out blocks and can deal with any problem that he may find in the cavity once he's cut out the blocks.

 

[butchdingle]

Whether a plaster can or can't do this, you'll have to ask. I could do it and I can plaster (sort of ) but I'm not a plasterer. So, the point is do you need a plasterer? No, what you need is someone who can plaster, can cut out blocks and can deal with any problem that he may find in the cavity once he's cut out the blocks.

Thanks for coming back to me - so do you think that the plaster in that room is just over the Thermalite Block?