Hello, new member in great need of help...

[saveasteading]

26 minutes ago, Ferdinand said:

do your gutters overflow in heavy rain?

A lot can go wrong with gutters.

too small

blocked in gutter or downpipe or drain

not level or not sloping to the outlet.

dipping at the wrong point

not at the right level

high flow at valley 

too few outlets.

 

How the water gets from the eaves to the lower floor where the problem is seen is another matter. 

It is possibly coming down the cavity. with the bead fill helping it to channel, then hitting an obstruction which makes it wet the wall at that point.

 

the amount of water that can cause that level of dampness is surprisingly small. Not buckets but mugs.

 

Gutter observation first, in all levels of rain.

[annec]

Thanks so much to all of you for your interest and suggestions. My husband renovated the whole house but we've struggled to get the right help with this problem, despite asking other tradesmen for their opinions.

 

He's reading all your comments and we'll decide next steps, based on your suggestions. Again, thank you all.

[annec]

1 hour ago, saveasteading said:

A lot can go wrong with gutters.

too small

blocked in gutter or downpipe or drain

not level or not sloping to the outlet.

dipping at the wrong point

not at the right level

high flow at valley 

too few outlets.

 

How the water gets from the eaves to the lower floor where the problem is seen is another matter. 

It is possibly coming down the cavity. with the bead fill helping it to channel, then hitting an obstruction which makes it wet the wall at that point.

 

the amount of water that can cause that level of dampness is surprisingly small. Not buckets but mugs.

 

Gutter observation first, in all levels of rain.

Saveasteading, I've only just worked out how to comment on a comment...wish I'd have seen this feature before now!

 

My one big issue is that these problem areas have never been in the slightest damp internally...the walls are dry to the touch but crumblung/bubbling/ furring paint.

 

We have a couple of small, seemingly unrelated damp patches in two rooms downstairs - one at the side of the front bay which is nowhere near the other areas and one at the patio door reveal at the back - maybe related.

 

The house is too high to see into the top gutters without scaffolding or a super tall ladder but all were newly replaced in the last 5 years or so.

 

The first of these problem areas started not too long after the kitchen room was plastered and about a year before the cavity wall insulation and at least two years before K-Rend. We had no idea it would affect other rooms later, as they were plastered, over time.

 

The 'sticking plaster' method others have mentioned is only the result of trial and error over the last few years, maybe 5. We had no idea we'd have an ingoing problem.

 

Interestingly, there have been three other areas on an adjoining wall which initially had the exact same problem but the first couple of sticking plater methods seem to have sorted these areas out now. They were absolutely not related to gutter or roof issues because they adjoin the neighbour.

 

I wish you guys lived locally so you could come and look - everyone we've asked is quite mystified.

[saveasteading]

I have met very few people who understand the movement of water, and it is especially worrying when, for example, roofers don't understand the basics of lapping and sealing. 

The problem is usually simple, and a surprisingly small hole, possibly far from the final problem.

OR coming up from the ground

The solution is usually NOT mastic, or paint sealing.

Without me reading the whole discussion again, can you remind me is the external render/paint breathable?

 

[annec]

4 hours ago, saveasteading said:

I have met very few people who understand the movement of water, and it is especially worrying when, for example, roofers don't understand the basics of lapping and sealing. 

The problem is usually simple, and a surprisingly small hole, possibly far from the final problem.

OR coming up from the ground

The solution is usually NOT mastic, or paint sealing.

Without me reading the whole discussion again, can you remind me is the external render/paint breathable?

 

It's K-Rend which is apparently breathable. It's been on around 5 years now but the initial problem began before it was applied...except we never realised how bad it would get, or how widespread 

[Mr Punter]

9 hours ago, Ferdinand said:

My best anti-moisture measure to make my rentals more resilient to tenant lifestyles is to fit a PIV loft fan

 

I had exactly the same recommendation from a builder I know who does loads of work on rental properties.

[saveasteading]

Too early to say, as finding the source is the best solution.

 

Cavity ventilation???

[bassanclan]

I'm assuming that this is a solid wall rather than a cavity wall.

 

In a solid wall victorian terrace I renovated i patch pointed a couple of square metres under a window, only to find it caused dampness to come into the house as the original pointing will have been lime and i had used sand/cement. I raked out what i had done and the problem went away.

[Dave Jones]

13 hours ago, annec said:

Saveasteading, I've only just worked out how to comment on a comment...wish I'd have seen this feature before now!

 

My one big issue is that these problem areas have never been in the slightest damp internally...the walls are dry to the touch but crumblung/bubbling/ furring paint.

 

We have a couple of small, seemingly unrelated damp patches in two rooms downstairs - one at the side of the front bay which is nowhere near the other areas and one at the patio door reveal at the back - maybe related.

 

The house is too high to see into the top gutters without scaffolding or a super tall ladder but all were newly replaced in the last 5 years or so.

 

The first of these problem areas started not too long after the kitchen room was plastered and about a year before the cavity wall insulation and at least two years before K-Rend. We had no idea it would affect other rooms later, as they were plastered, over time.

 

The 'sticking plaster' method others have mentioned is only the result of trial and error over the last few years, maybe 5. We had no idea we'd have an ingoing problem.

 

Interestingly, there have been three other areas on an adjoining wall which initially had the exact same problem but the first couple of sticking plater methods seem to have sorted these areas out now. They were absolutely not related to gutter or roof issues because they adjoin the neighbour.

 

I wish you guys lived locally so you could come and look - everyone we've asked is quite mystified.

 

how is the kitchen vented to the outside ? Same with bathrooms, showers etc ?

 

You say the problems started after kitchen was plastered, hence looking at vent/extraction. Is the extractor been moved/knocked and is venting into the cavity maybe ?

[MikeGrahamT21]

You need some measurement tools to start off.

 

Get yourself a hygrometer, and also a moisture meter, one to see how humid the environment is, and another to do spot tests and see just how humid the materials are. They are very cheap to buy, but will give invaluable information as to whether this is indeed moisture, or some kind of chemical reaction happening.

[Triassic]

On 07/10/2021 at 06:46, bassanclan said:

I'm assuming that this is a solid wall rather than a cavity wall.

 

In a solid wall victorian terrace I renovated i patch pointed a couple of square metres under a window, only to find it caused dampness to come into the house as the original pointing will have been lime and i had used sand/cement. I raked out what i had done and the problem went away.

Is the damp only on external walls? Are the external walls of solid construction, no cavity? If so, the damp might be due to the use of modern plaster rather than the more breathable lime plaster. We had a similar problem in a house with solid stone walls, once the modern plaster was removed and replaced with lime plaster the problem went away.