Saturday 11 July 2015

A full-scale assault on the Living Room

WARNING: This is quite a long post because I'm on my soapbox a little bit, but if you get through it I promise you will learn some important stuff about damp that may come in useful one day, whether your own house is old or new. Scout's honour.


A lifetime ago when we first got the keys to The Lodge we decided, for reasons that still escape me to this day, to take a celebratory hygrometer reading in the Living Room. Perhaps we were out of cocaine and party poppers, I dunno.

The truth is that even in the colder months we could feel the humidity in the house, particularly downstairs where there were hints at moisture-related issues that went beyond mould on the walls, and we wanted to chart our progress in the battle against it. So we bought a doodah.
Eleven weeks later the fight is still on, with the dampness laughing in the face of the unseasonable summer heat (which barely penetrates the building anyway) by regularly sending the hygrometer towards 90% humidity, which is neither good nor healthy.


An unusual reading - it's normally deep in the blue
Long ago we pulled out the rubber underlay and carpet - which was revolting, stripped the wallpaper and had the windows open almost constantly to get the air circulating and the moisture out.
Despite gypsum plaster walls still being in the room we thought that these initial measures would start us off in the right direction, but whereas the hygrometer would occasionally dip in to the green 'mmm, I could get used to this' humidity range for brief moments here and there it has been in the blue 'tropical rainforest' range for the vast, vast majority of the time.

Putting aside the idle (but genuine) theory that there might be a spring under the house, this week we decided to attack the living room and take no prisoners in an effort to find out what was going on.

First of all, however, a word about dampness in old houses. Here comes my soapbox.
To be blunt about it: ...they're supposed to get damp. The trick is in how that dampness is managed.

Take an old brick from, say, 1855 and a brick made in more recent times. Hold one in each hand. Go on. Don't argue with me, just do it. I'll tell you why in a minute.
Without going into detail that I don't pretend to fully understand anyway, bricks were hand-made in the Victorian era - the clay and aggregates manually formed and fired. As such they weren't all that dense and could even be a bit crumbly because of impurities. And even then, if you came across a nice sturdy example, the next brick that was made by the same person would likely be completely different. There was no consistency, such were the comparatively primitive processes involved in their manufacture.
So this 'soft' brick would absorb rainwater or condensation naturally as part of its job. Not like a sponge, of course, but you get the idea. Left to its own devices, that same water would naturally let itself out again from all available sides over a period of time. This is generally known as 'breathing'.

In... out.
See?


Old vs new(er)
Now, have you noticed that the modern brick in your other hand not only looks different but may be heavier and doesn't crumble even a tiny bit? Yes?
That's because 160 years has seen the brick-making art perfected - now there's not just clay and wotnot in there, there's a whole load of other stuff too including hardening and waterproofing chemicals and ingredients that toughen the whole machine-made thing up and make it so dense that there ain't never no water getting in to that bad boy or any of its identical siblings. Not ever. No sir. As waterproof as a turtle's lipstick.

So looking at a brick Victorian house like The Lodge and thinking it's more-or-less the same as a brick house built in 2015 is like comparing a cardboard box to a plastic storage tub and concluding that they're the same thing. They're not. They're miles apart and have to be treated entirely differently.

And that's why using new building materials in an old house is a massive no-no.
Doing so is likely to start gradually killing your lovely home, although - as we learnt pretty quickly during this process - it's astonishing how many builders and so-called 'period property professionals' either don't know or don't care all that much. Modern materials are cheap, common, less complicated to work with and faster to use. So these people use them despite the harm they're doing and besides, what are the chances of the starry-eyed new homeowners being armed with such knowledge? Pretty slim. We've seen it a million times, even on some of those high-end TV property shows that we all know and love.
Hi George! <waves>


Concrete. Evil.
I really don't want to bore you by picking over all of the bad things that can be done with modern materials, so I'll simplify it: Anything that stops an old house breathing properly, either from the inside or the outside, walls, floors or ceilings, is bad. Basically, anything that is impermeable to moisture. And the main offenders are cement, concrete and gypsum (that pinkish plaster stuff that new walls tend to be made of). These things stop water going anywhere and will make your house crumble.

So back to the Living Room in The Lodge.
The external west wall of the room - as with the rest of the lower floor - is hand-hewn sandstone which naturally absorbs water, just like soft Victorian bricks. They're supposed to.
In an ideal world and had the building been looked after at all in the last 150-or-so years, these blocks would have been stuck together with lime mortar and the internal surfaces dressed with lime-based plaster then decorated with some kind of lime-based paint.

Lime breathes, you see.

In fact lime (particularly lime mortar/pointing) helps wick moisture away from vulnerable soft bricks and breathe it out so that the bricks don't have to suffer the stresses and strains of doing it themselves 24/7, thereby prolonging their lives and keeping your house upright.
But do it with a cement mortar and you're either trapping the moisture in the wall altogether or forcing it to breathe back out through the front surface of the bricks alone, making them work so much harder. So while your sexy cement pointing may look fantabulous for decades to come, here's what happens to your bricks (or sandstone) as they're forced into early retirement:


This is known as 'spalling'.
Moisture that can't get out because of the cement pointing
stays put and weakens the brick. When winter comes and
the water freezes it expands and off pops the front.

Anyway, having taken a hammer, bolster chisel and hammer drill with a scutch comb attachment to the Living Room wall, here's what I found, looking from the outside to the inside (blue = good / red = bad):

Layer 1 - Sandstone (part lime pointed / part cement pointed)
Layer 2 - Victorian brick (lime pointed)
Layer 3 - 3/4" solid cement-based bonding coat
Layer 4 - Thin gypsum plaster skim
Layer 5 - Vertical wooden battens with strips of bitumen behind them
Layer 6 - Gypsum plasterboard
Layer 7 - Thin plastic sheeting stapled to the plasterboard
Layer 8 - More gypsum plasterboard
Layer 9 - Thick gypsum plaster skim
BETWEEN - At least six layers of wallpaper ranging from gloss-painted woodchip to vomit-inducing flowery patterns

It quickly became obvious that previous tenants over many decades had been having trouble with damp in the room, and numerous disastrous attempts had been made to sort it out with impermeable materials.
The net result of all of these red layers is that the only option for moisture being absorbed into the sandstone on the outside was to go back out the way it came. And if it can't breathe out through a conduit like lime mortar on the outside, it has to release through the stone, which weakens it. To breathe away unnoticed inside the house too, it would need lime plaster. And these gypsum layers mean that the moisture could have become trapped in the stone. It would have been far worse if the outside walls were concrete rendered, trapped the moisture in the stone with nowhere to go, but we're lucky in that the stone has been left bare.
By the same token, condensation and moisture-laden air on the inside (caused by human beings - cooking, showering, even breathing...), was also meeting these barriers in the wall and had nowhere to go either, especially because the windows were never even opened and there was no airflow going through the building at all. We know this because of mould on the walls elsewhere and the vents in the awful uPVC window frames having been Sellotaped-up for so long that the tape was starting to go brittle.

And with the very first inside layer being gypsum plaster, here's what had been happening on one of the Living Room walls, where the moisture was simply condensing:


Damp wrinkly wallpaper with a hideous design on top of water-impermeable pink gypsum plaster


Most people who hadn't read the above diatribe would automatically throw their hands up in horror, thinking they had rising damp in the walls, and would eventually call a 'specialist' who would rock up in his £40,000 Range Rover (private plates), scratch his chin thoughtfully, tut for a bit, then persuade you to part with many thousands of pounds for damp-proof courses and chemical injections, membranes and various high-tech cutting-edge 'solutions' which aren't needed and wouldn't solve the problem anyway.
It's a mug's game - all that's wrong is that their walls are skimmed with gypsum plaster that the moisture can't breathe through and they probably don't open the windows enough to get air flowing around the house.
See the spots of discoloured or mouldy wallpaper behind your wardrobe? Same principle - not enough airflow to whisk the moisture away, so it condenses on the wall.


Trevor and his spade. Note the plasterboard
and corrugated bitumen over the original
bricks. The odd-coloured wall on the right
is original lime (dabbed with modern filler).
Back in the Living Room again, it goes without saying that I removed all of the Bad Things from the west wall and banished them from the house without any supper.

Thursday saw the return of the unstoppable Terminator Trevor who did away with the limiting formality of using proper tools, and instead simply beat the hell out of the next wall with a garden spade.

This particular internal gypsum-plastered wall (the same one with the wrinkly paper, above), which has Toilet 1 on the other side, had a large gypsum patch at the bottom where it had been repaired for some reason and I had convinced myself that there could be no other reason than excessive amounts of damp coming from somewhere as-yet unknown.
Disappointingly we couldn't work out why the patch was there in the end, but we did find the entire wall had been clad in weird corrugated tar-based bitumen as some form of 'tanking' against moisture, then skimmed over. The original lime-pointed brickwork behind was so dry that it was dusty to the touch.

The next wall to be clubbed into submission by Trevor* was in the dog-leg nook of the Living Room, still with Toilet 1 on the other side.
This set-up was much the same as the many-layered first wall, complete with plastic sheeting and bitumen behind the battens, presumably to stop them rotting in the mysteriously-absent damp. However this time the final layer before we reached the original bricks was actually lime plaster, although it was a) falling apart, and b) painted over with waterproof paint. Still, the thought was there.


Most of the gypsum walls had been lined
with plastic sheeting
As three of the four remaining walls were original lime (albeit featuring dozens of smears of Polyfilla) all that remained to be stripped was the north wall into the Courtyard at the back of the dog-leg. Surely there had to be evidence of damp in there?
No. Not a bit. Just more plastic and horrible wallpaper.

There was, however, something that has piqued our curiosity in the dog-leg as a whole.
It used to be another room, presumably with a specific purpose - but what was it?

First of all it was definitely another room because we found where the bricks that separated it from the now-Living Room had been roughly cut off, and there was evidence of an old doorway on the floor, leading from the Living Room in to this small nook area. We also found one side of the original door frame beneath the many layers of plasterboard.
There are four half-brick-sized recesses in the west wall of this new small room, set out in two rows but with no corresponding holes on the other side.
Beneath those we found a thin sheet of slate in poor condition, roughly about 10mm thick, had been stuck to the wall. About 8" deep (to mix my measurements) it ran horizontally from the ex-wall adjoining the living room to the other end of the wall then turned along the north wall briefly, stopping at the window.
Immediately below this, on both walls, the brickwork had been heavily cemented and on the east wall of the nook we found an old copper pipe emerging from the wall just above head height that had been cut off, suggesting that there had been a water supply to the room.


Note: chopped-off bricks (left) showing it used to be another room; the four recesses;
a line of slate about three brick courses deep and concrete walls/floor markings
that suggest there was something big, heavy and rectangular there.
The best theory we have so far is that it was the gamekeeper's meat preparation room. Like a butchery.
Perhaps the slate was a kind of splashback for a heavy stone sink or butcher's slab and the holes in the wall held timber that supported strong shelving. It's strange that the room was accessed from the now-Living Room, but it's likely that that purpose is a more modern element and the room was something else entirely.

Theories are welcome from out there in cyberspace, and if you can back any up with website addresses that would be just wonderful. Mainly because we're Googled-out and can't find anything.

And here endeth the blog post that has taken me three days to write. Thank you for reading this far down. Once we've given the room time to breathe a little bit I'll update the blog about the humidity, but for now it's looking positive - we seem to be in the green much more than the blue lately.

You can put your bricks down now, by the way. I should've mentioned that a while back...


  • For more info about damp and condensation in old buildings by someone who actually knows what he's going on about, go to heritage-house.org where Pete - who surveyed The Lodge before we bought it - will happily talk about it until those proverbial cows come home.


* I managed to hurt my right forearm and my abductor pollicis longus muscle - yes, I Googled it - has swollen so much that I needed to use an ice pack the evening before, so I was relegated to tea-maker, wheelbarrow-pusher and clearer-upper for the day.

1 comment:

  1. Oh God - I can't stop laughing! You guys should be on the telly... fantastic to see its coming together - I reckon that's going to be a fantastic house when you get it sorted..

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