Water ingress analysis and rectification

[prophet01]

Evening all

Issue:
Partner's having water ingress issues at her place, causing interior damp, and has sent these images.

My (ignorant of roofing) diagnosis:
Excuse the probably incorrect terminology but it appears to me that the ingress is due to:
1. Disintegration of verge cap bedding mortar
2. Disintegration of brickwork joint mortar

Others' views would be much appreciated

Rectification:
On the initial assumption that my diagnosis is reasonably accurate could she get away with repointing the capping tiles without having to take them off and re-bed them, and repointing the brickwork?

Thanks.

 

[datarebal]

was always destined to fail;
First the ride has no cover over the brickwork . The wall wont move but the roof being timber would settle. mortar would then crack.
Best bet here is remove the half round ridge tiles. Replace with mono ridge which are designed for this detail.
Also take a close look at the short rear verge from the main roof there should be a lead saddle weathering the change of angle.
. and check the gutter there too

 

[prophet01]

@datarebal
Thanks for the response.

"was always destined to fail"
Indeed. What were they thinking.

Best bet here is remove the half round ridge tiles. Replace with mono ridge which are designed for this detail.
Would this detail01 suffice?

Also take a close look at the short rear verge from the main roof there should be a lead saddle weathering the change of angle.
Is this what you mean? See composite image08 & image09. What's your assessment?

 

[prophet01]

I think it would also makes sense to simply extend the guttering to completely by-pass this concentration of run-off away from the start of the gully at the wall.

 

[datarebal]

First image at ridge to verge detail is poor there appears to be a piece of grp or muck stuck in the trough of a tile.
its stopping nothing
it requires a lead saddle from under the first verge tile (and cut tile) dressed down over the top of the GRP valley that's in place and under the first ridge tile with a turned up edge. then the ridge fitted.
The valley is cut to wide and water check ridges are on show and no doubt the mortar will have slumped over the hidden edge under the tiles. this will draw water back into the roof.

Gutter, if the ridge to valley detail was correct it should be fine (needs a clear out though)

The detail in the drawing showing the mono ridge is correct

The wall top brick courses are already suffering due to constant damp and freeze thaw erosion.
Hopefully the timber plate under the head of the tiled roof is still sound. but worth check

simply pointing odd bits up wont work

and FWIW tile gauge at the top of valley looks ott .. measure the exposed tile length

 

[prophet01]

@datarebal
"First image at ridge to verge detail is poor there appears to be a piece of grp or muck stuck in the trough of a tile.
its stopping nothing..."
Looks to be a bodge job.

I've only seen the images so will get up on the roof next week and properly inspect.

At the moment I'm thinking to:
1. Re-point brickwork
2. Replace existing half rounds with mono ridge, about 5m in length.
3. Install lead saddle as per your suggestion.

"The valley is cut too wide and water check ridges are on show and no doubt the mortar will have slumped over the hidden edge under the tiles. this will draw water back into the roof."
Is this an easy fix? If not perhaps just do actions 1-3 and monitor.

 

[datarebal]

Start with 1-3

The valley work is easy enough if its what you do. if you can do the ridge and saddle then the valley shouldn't be a work up
Someone has been at it in the near past.
.

 

[prophet01]

No, it's not what I do. 40 years of highway and bridge engineering (design and construction project management).
Never touched a roof before but could do 1-3. Most likely instruct a builder/roofer.

How much would you estimate the cost to do 1-3.

 

[DiyNutJob]

Looks like the bricks were repointed before. This could work if you do more of the same. All the cracks have to be filled. It's a perfect job for an aluminium scaffold, plenty of room and not high.

 

[prophet01]

Yes, less than £100/week hire.
Could do the pointing and replace the ridge tiles from it. Pretty basic stuff really.

 

[DiyNutJob]

You have to seal the cracks in the bricks as well. Perhaps transparent hybrid polymer sealant could work. The sealant should become dull and grey once weathered.

 

[datarebal]

transparent hybrid polymer sealant could work.

Or you could do the proper job and forget

 

[kp00110]

why would you point bricks with sealant? Mortar is a structural component of how a brick works

 

[DiyNutJob]

why would you point bricks with sealant? Mortar is a structural component of how a brick works

You wouldn't, nor would you "point" cracks in brick with mortar. Wouldn't fit.

 

[DiyNutJob]

Or you could do the proper job and forget

What's proper? Dig the brick out and risk structural damage?