It takes brickwork a long time to dry out

[malcolm]

For years the gutter has overflowed and tipped water down the wall. The gutter was fixed and waterproof paint removed from the brickwork about 2 months ago, and the wall was re-pointed last month.

The new lime mortar changes colour when it gets wet, and there is a damp patch where the gutter used to overflow which still hasn't dried out after two summer months when it has been well sheltered from rain. The wall must have been very wet but I am surprised it is taking this long to dry. There are no water pipes in the area so it must just be the damp escaping.

Just a thought the photo might be useful to anyone else trying to fix internal damp problems who wonders why the damp isn't fixed months after the appropriate work.

 

[Flyfisher]

One inch per month is a figure often mentioned on here (and often repeated by me :lol: ).

The figure will likely be hugely variable depending on precise conditions, but I wouldn't be worrying about the wall still being damp after only two months, especially if the guttering has been soaking the wall for many years, which suggests it should be pretty much completely sodden

At least you've fixed the problem at a good time of year and you should have at least another two months of good weather (on average) for drying out.

 

[Keithj]

Stone and lime, not brick, but the church wall that had been damp for at least 50 years has taken over a year to reach the point where the efflorescence has stopped.

Patience is essential!

 

[malcolm]

I was just surprised that the outside face exposed to sunshine and wind took so long to dry. I had imagined the outside would dry quickly and then the inside would dry slowly over several months without making the outside noticeably wet.

Though the barn brickwork had a lot of salts coming through for a year after paint stripping, and I was surprised how much water a completely dry brick from an internal wall sucked up when fizzing in a tray of water. Maybe I should not be so surprised.

 

[88v8]

I was surprised how much water a completely dry brick from an internal wall sucked up when fizzing in a tray of water.

Were you trying to disprove the theories about rising damp, or is this some sort of masochistic loofah?

Ivor

 

[noj]

I lowererd the external ground level, sorted out the rainwater disposal and then removed the vinyl floocovering in our utility room and it's taken just over two years for the brick floor in one corner to dry to the point that it's no longer visibly damp. If I hadn't had more pressing things to do I might have been trying all sorts of extra stuff to solve a problem that was already fixed...

It seems a crazy amount of time for a little bit of water to evaporate - but then I have no problem understanding that a 9" oak log, split to woodburner size and stored rain free with agood airflow needs at least two full summers before it's dry enough to burn happily.

 

[Flyfisher]

It seems a crazy amount of time for a little bit of water to evaporate . . . . .

I suspect this is the root of the confusion. As mentioned above, brickwork can absorb a great deal of water so it's not always a case of 'a little bit of water' evaporating.

Also, and this is pure conjecture on my part, but my feeling is that it's probably better for buildings to slowly settle into a new environmental equilibrium.

I reckon keithj is dead right about patience being essential.

 

[MatthewC]

I reckon keithj is dead right about patience being essential.

And we always advise newbies to make decisions slowly once they have tackled the major issues. I think it took my house two whole years from when I did the roof to reach the right level of dryness (i.e. that's when the painted wood stopped shrinking!)

 

[malcolm]

Were you trying to disprove the theories about rising damp, or is this some sort of masochistic loofah?

I was re-using the brick and noticed the surface dried instantly after a quick spray. It took five minutes of fizzing in a tray of water to increase the drying time to something more suitable for lime mortar. The remaining bricks are stored outside now.

I wonder how much weight the extra water must add to a completely sodden wet house (modern exterior paints or concrete render, poor drainage etc). It might be a lesser issue than the attendant wet joist ends, but must be considerable.