Cement render saved my house?!

[tycarregydwr]

That was unexpected. The conservation builder who came out last week - and with whom we had a lovely tour today of several amazing projects they've done - thinks that the hideous cement pebble-dashing might actually be keeping my house dry.

It's a late 19th century Victorian stone house - not a cottage exactly, slightly posher farmhouse style with evidence of quite good workmanship. From old photos and a thorough examination of what remains, she thinks that it was indeed originally bare stone, and not lime rendered. Unusual certainly, but not unheard of in the time period and there's good reason to believe this was the case. At some point, probably in the 1950s-70s, the weather wall only was rendered with cement pebble dash - as well as the floor being concreted. Now, there HAS been damage at some point - the first floor joists rotted in the wall and were repaired at least twice, though no idea when. BUT at the moment the house is dry. Floor is dry, walls are mostly dry (only damp as been obvious, localised penetrating damp due to broken gutters and drains, and at least two areas of this are where there is still lime plaster). Even the damp specialist was impressed. And two conservation builders have agreed that it is very surprising that it's dry, but that it is.
So we have discussed hacking off the modern plaster in the front room, and the cement off the outside - and either just restoring the lime pointing and leaving it at that, or considering lime render if needed.
But then the (highly recommended) bod said that upon further reflection, she wonders if the cement might indeed be 'sheltering' the house and keeping it dry, and we may want to consider leaving it, possibly painting it to make it less hideous.

At the moment I think we are planning to take the plaster off the inside so that we can properly assess the wall. If it is actually wet inside the wall, well then the cement isn't working and we're back to thinking it needs to come off. But if the wall is as dry as we expect it to be, ??? Is this the only case ever of cement actually working on a solid wall?

 

[DJH]

Snap! I'm convinced that my house has been preserved by it's coat of cement based render. I've mentioned it before on the 'Installing Sash Windows' topic. For Hundreds of years it would have had a coat of white wash but I'm sure that if it hadn't been rendered irreparable damage would have happened during the last 60 years it's been stood idle.

 

[GRADE_II_MONEYPIT]

Anything is possible but personally do not believe that cement render will have had any positive effect on any traditionally built houses.

I have had poor advice from my CO and from several so called conservation builders so beware they are not the final word on the subject.

 

[JoceAndChris]

Hmmm. My house can't deal with being naked stone, and so in that regard is protected by the cement render. We've chipped off the very very very thick cement render in places, and this wet year has saturated the porous rock underneath. It was never intended to be naked but to have a lime render and layer on layer of what is often termed sacrificial limewash.

If the cement render could stay perfect and never crack it might be OK ( though it's said the cement and the stone move differently and that makes problems). The cement cracks though, the rain gets in, can't get out, and then you have an unseen problem that could be eroding away a spot within. So whilst it might be protecting one part of your property it could be damaging another. Eventually, it's going to fail, and then what do you do?

All houses have to be judged case by case and it could be that this is an instance where it isn't causing undue problems so leave it alone. Also the Victorians very often pebble dashed and stuccoed properties and stripping them is often the wrong thing to do.

In our case though, it's blatantly unsympathetic and has caused localised spots of damp on the inside. It's coming off!

 

[middi]

Ther is nothing wrong with cement renders as far as doing a " job " is concerned,

----BUT-- ( and a BIG but) , using cement renders on house elevations costructed to be breatheable ( external) walls is a death sentence ( unless the actual walls are heavily modified and insulated). Also if cement renders crack and water gains access a lot of damage can occurr due to trapped damp and frosts.
Using cement renders on stone houses elevations will offer protection to the stones and will hardly interfere wth bretheability. But, if cement renders is used on very soft limestone, soft red bricks or even worse timber frames elevations it may well make a vere deterimental difference.

What do they say? " horses for courses"
( Mind you , and for the life of me, I don't understand why would someone spoil the look of a stone house with cement render)

Middi

 

[JohnB]

( Mind you , and for the life of me, I don't understand why would someone spoil the look of a stone house with cement render)

Middi

It depends what they've done to the stone house before rendering it!

 

[middi]

Only a preference of mine John. I would more than likely spend hours and hours of correct repointing and repair work just for the pleasure of eventually enjoy looking at the stonework. Admit that a faster approach with cement render will probably " save the day" and much cheaper

Middi

 

[JohnB]

Only a preference of mine John. I would more than likely spend hours and hours of correct repointing and repair work just for the pleasure of eventually enjoy looking at the stonework. Admit that a faster approach with cement render will probably " save the day" and much cheaper

Middi

You're welcome to take out the botched up, cement mortared stone and brick work used in the 60s to move and resize my window openings, and block up a doorway. Plus replace the concrete lintels with timber and brick ones at the original height. I'm still to uncover the horrors committed upstairs . I've discovered I have what used to be a pair of double fronted houses.

My cement render sticks nicely to stonework built with cement mortar, and doesn't seem to result in wet walls. It's the clay mortar it doesn't like.

 

[88v8]

That was unexpected..... the (highly recommended) bod said that upon further reflection, she wonders if the cement might indeed be 'sheltering' the house and keeping it dry, and we may want to consider leaving it, possibly painting it to make it less hideous.

Ask three experts, get four answers... Sounds as if you've been lucky to find someone who isn't myopically set on promoting one 'solution' to a building's problems. Although I've been persuaded as to the logic of lime, and have done a bit of cement eradication here - a floor, some pointing - I don't doubt that in some cases a waterproof coating such as cement render could work OK. I've inherited some panels with cement render, plus some plastic-emulsioned daub, but have moderated my original thoughts of rushing to remove it.

Each case on its merits... each part of the house on its merits... if that part of the house is dry, let well enough alone, I'd say.

Ivor

 

[tycarregydwr]

Please don't misunderstand - I completely understand the theory of lime and of why cement is bad - as does this builder - recommended by JohnB and with a solid pedigree of 'right thinking' on old houses. And as I said, she herself was surprised at this idea, as she normally goes in for the restoration approach.
And also, the house was originally bare stone. Yes, I understand this was unusual. But it wasn't unheard of in the late Victorian period. The Victorians were the ones who started removing lime render, the so-called 'rubble worship'. And in the late Victorian period, they did start building bare stone walls - this is documented. In our case we are convinced this was the original construction. We base this on old photos, on the the fact that the rear wall (non-weather wall) of the house has never been cement rendered and is still pointed with its original lime pointing, and is bare stone with absolutely no indication that it was ever rendered or washed at all. In addition, on one of the side walls we have access to the side of an original window opening (now a doorway into the modern extension). The beautiful decoration brick surround is flush to the stone. Builder says if the house was originally rendered, the brick surrounds were built standing proud so that they would not be covered with render (as these are clearly decorated and intended to be seen).

 

[Carol]

As I contemplate the water ingress after the removal of my cement render last year, I think I should have probably left well alone! Builder has refitted gutters, checked tiling and leadwork and still I have a patch about 50cm square where the water is seeping in through the lime render after heavy (normal for Somerset) rain . Next step will be the Keim paint option on the whole wall and more expense.

However, on the rest of the rear wall it enabled us to see that the original timber frame had been removed many years ago and the stonework which replaced it was in reasonable condition below the concrete. now lime.

 

[DJH]

I inherited the cement render when I bought the place and with no sign of damp inside I don't intend to remove it. The original dwelling here, the single storey on the left in the picture is built from clay on a cobble base, whitewashed both inside and out, with an outer stone skin built on about 1895 dated from the coin we found, when the tin roof was erected over the thatch. This had doors front and rear and the animals were on one side of this single room dwelling and the family were on the other.


The only wall that hasn’t been rendered with cement mortar is the North elevation but that has been patched here and there with it.



South elevation



Original dwelling wall at the North window which was originally the door the stock entered/exited



I still maintain that the coat has kept the building both protected from the elements and dry. If the walls were dry when they were rendered and the many coats of whitewash have meant the render has adhered to that and not the wall itself what harm has been done?

 

[DJH]

Carol, South Somerset? Sounds like my neck of the woods. Ham Hill stone buildings. Perry's Cider................

 

[TheForge]

...Burrow Hill Cider too!

 

[DJH]

Castle Reclamation.........

 

[Carol]

We are in the top right-hand corner, hills, woods and rain and more than your average number of schools! And more like Doulting stone than Ham.

 

[TheForge]

Castle Reclamation.........

And as the road past Castle Rec/Parret Works was earlier!

 

[Carol]

So that is why it's called Somerset. Only fit to live here in the summer months, we should all be taking to the hills, and in some villages they still are!

 

[DJH]

It's bad in Muchelney I hear.