Damp half way up external wall

[Barney Williams]

Hello,

After some heavy rain late last year I noticed a damp patch part way up the wall by our front door. While that seems to have dried out I would obviously like to solve the root of the issue. I noticed the corresponding patch of exterior wall is discolored. I have marked the area on a pic.

1. It gets worse when it rains
2. I have had roofers come and look at the main roof and bay window, they both thought they seemed fine.
3. When I looked back on google maps I noticed this patch has been discolored as far back as Aug 2018 (last time google updated our street), see pic, but the internal wall only recently showed any sign of damp.
4. I noticed there are several holes in the mortar, I never noticed them before but have been here about 13 yrs and we didn't make them so they must have been there.
5. On one of the close ups you can see some wood in the mortar on the angled face to the left. I have just drilled this out on the assumption that could be allowing water to penetrate (although it is at the bottom of the affected area). I found there was a thick wire running through.
6. There is no plumbing on that side of the house, no radiators, sinks, bathrooms etc.
7. The damp does seem to extend into the mortar of the window pillar but not right around to the window itself (which seems well sealed).

Is it possible its just those holes in the mortar allowing water penetration? I am at a bit of a loss after ruling out plumbing and roofing so any ideas massively appreciated.

Thanks,
Barney

 

[KenGMac]

Barney Williams, good evening.

The missing mortar could be causing the issues around the front entrance door, I take it that the dampness is confined to the area of the door?

As a rapid [cheap] fix suggest you consider ?? injecting the holes with a silicon mastic, do not bring the mastic anywhere near the surface of the mortar or indeed the pointing, use the nozzle to squirt mastic into the depth of the holes.

Why? it is a fast, cheap, quick method of finding out if indeed the missing mortar is indeed the source of the issues.

if the mortar "Trick" works then in the summer you can rake out and re-point, you would be advised to re-point the entire area of brick so any local patch is not standing out like a sore thumb.

As for drying out internally? suggest a small fan no heat needed, just an enhanced air flow over any damp plaster internally, if you think about it, if you put the washing out on a windy dry day it will dry very fast, but the same washing on the line with no breeze and the washing takes forever to dry?

Ken.

 

[JohnD]

Look closely as the gutter round the bay window. If there was a leak, or a leaf blockage, or if it sags, it could run down that corner. Watch next time it rains.

Chemical injection is a bad sign, and does not cure the source of water.

Please show us photos of the inside of the damp walls.

 

[Barney Williams]

Thanks @KenGMac - so sort of half fill the holes with silicon?

Hi @JohnD , I did clear out the gutters after the damp initially showed on the internal wall and both the roofers seemed to think the roof/gutter looked okay, although I guess that does not 100% rule out a leak somewhere in that region, it doesn't take much we weather for it to worsen. By contrast I had the same issue on the other side of the window at the same time caused by a blocked hopper, unblocked it and the mortar has since dried out.

Agreed on the injection I mainly highlighted it because one of my initial thoughts was water getting in higher up somewhere and hitting the DPC and pooling there but its too high for that it seems?

Unfortunately I seem to have deleted most of my pics of the damp on the internal wall. I may have them backed up somewhere, in the meantime this was the only one I could find, It probably extended a similar distance beneath the dado rail. you can see the middle hinge of the door on the right as a guide to compare it to the outside location.

 

[JohnD]

your inside pic shows a huge amount of water. Unless there is a leaking water pipe buried in the wall, it must surely be rain cascading off the roof, or possibly the head of the front doorway if it has one. It's more than could get in through a few little gaps in the pointing and ordinary rainfall.

 

[Barney Williams]

Thank JohnD. I'm still convinced it is something related the bay roof. I suppose neither of the roofers ruled it out 100%, they just couldn't see any issues and didn't want to charge me for a load of speculative work that may not even fix it.

I have booked in a damp surveyor to take a look, so will see what they have to say.