Cement Render - should it stay or should it go...

[harkerhill]

I have a solid brick built house (no cavity) - external is covered in painted cement render.

Now I can't afford to get the house re-rendered in lime at the moment, but my question is, is is better to have no render on the walls or have cement render?

I can start removing the render myself - but it's going to take a long time. I am probably about 1-2 years away from being able to re-render the outside again.

I'm concerned that the render is locking in the damp and it's affecting the plaster inside.

Any advice would be appreciated.

 

[Peter]

Unless the render is practically falling off you will not get cement render off without damaging the brick faces. I wouldn't leave that exposed for 1-2 years. If the render is cracked it will be trapping moisture behind it.

 

[Moo]

This morning, during a stroll round Southwold, I saw a most interesting end of terrace wall. It had been painted with some sort of black material that had (presumably over the course of many years) dried into a pattern reminiscent of crazy-paving. On some bricks, however, it was still solid and was coming away, taking the face of the brick with it. Does anyone know what this substance is/was?

And another one for the chamber of horrors:
Terrace of humble cottages fronting straight on to the pavement (Southwold price, just under a quarter of a million); all with two air-bricks just above the pavement (under floor level?).
One of the middle ones boasted a row of damp-proofing holes and a new air-brick in the wall above them (above floor level?). The old air-bricks had been carefully blocked up with what looked like pieces of dowel.

 

[Gervase]

In fishing towns like Southwold tar was commonly used for all sorts of things, as it was readily available. That crazes with age.
Lapboard and other timber was also treated with a creosote-like concoction called 'kutch' - a fishing net preservative which gave a mid-brown stain. Resourceful bunch, our ancestors!

 

[Moo]

Thanks, Gervase. That's v. interesting.
But how do you explain the tar lifting the whole surface of a brick?

 

[Mark]

HarkerHill

dos the render go right down to the ground ? What makes you think itsw locking in moisture ?

As a short term measure I would think about hacking off 6 inches from the ground and limewashing the rest of the render - just to fill any cracks on a short term basis.

btw - I my grandmother used to live in either your house or one of your close neighbours when she was a child. I know there are not many houses there - assuming you are the one between Stokesley and boro ?

 

[Gervase]

Those Suffolk bricks are very soft. The first house I ever bought was just outside Lowestoft, and had the most lovely warm red bricks, but they were incredibly soft - you could cut them with a handsaw.
I imagine that once damp gets behind the tar and freezes it 'blows' a scab off the face of the brick.

 

[Sue Wilkinson]

This morning, during a stroll round Southwold, I saw a most interesting end of terrace wall. It had been painted with some sort of black material that had (presumably over the course of many years) dried into a pattern reminiscent of crazy-paving. On some bricks, however, it was still solid and was coming away, taking the face of the brick with it. Does anyone know what this substance is/was?

No, I don't know, but I have a horror story too. Noticed only yesterday. A farm house in the village has recently sold at auction. Whilst people were viewing it someone must have prodded at what appeared to be a blown bit of masonry paint on a gable wall. This wall has looked like it needs attention for a while. However once someone started others have pulled, and the whole layer of paint comes away in sheets and is on a sort of hessian looking backing material that must have been stuck on the wall.

The good news is that the material comes off the brick quite easily by the looks of it, and the paint is stuck to the material so that comes off too. The brick beneath needs attention, pointing etc, but its not in the state I thought it would be.

Anyone any idea what that could be?

Sue

 

[harkerhill]

HarkerHill

dos the render go right down to the ground ? What makes you think itsw locking in moisture ?

As a short term measure I would think about hacking off 6 inches from the ground and limewashing the rest of the render - just to fill any cracks on a short term basis.

btw - I my grandmother used to live in either your house or one of your close neighbours when she was a child. I know there are not many houses there - assuming you are the one between Stokesley and boro ?

Mark - I'm really interested in this if she did and it was my house - can you PM me your phone number - I'm interested in old photos or stories about the house. I've been finding it hard to find any history of the house.

Thanks

Dean

 

[zunetunes]

.

dos the render go right down to the ground ? What makes you think itsw locking in moisture ?

As a short term measure I would think about hacking off 6 inches from the ground and limewashing the rest of the render - just to fill any cracks on a short term basis.

Two questions:
Is it ok/desirable to limewash over modern paint? Will hacking off 6 inches make any difference with drying out?

 

[Mark]

"Two questions:
Is it ok/desirable to limewash over modern paint?
Will hacking off 6 inches make any difference with drying out?"

You can limewash over modern paint - but it might not take very well - you can try on a test area. My reasoning was that the limewash could fill any fine cracks that might be letting water in through the render. It isnt ideal but in the circumstances it is cheap and could be worth trying. Obviously taking off the cement render is a better idea, but not knowing what the state of the wall is underneath you could be letting yourself in for a lot of extra work and cost doing that. It would be a short term measure.

Taking render off at the ground can make a significant difference. On houses with a damp course (slate or whatever) it stops the render bridging the dpc and on properties without dpc it still helps improve the breathability - worked wonders for us anyway.

ground levels, gutters, drains, etc all apply.

 

[Gervase]

Is it ok/desirable to limewash over modern paint?

Limewash is generally awful when applied over modern paint, particularly alkyd paints. If you make it with plenty of tallow it will cover and remain for maybe a season, but you'd have to repeat at least once a year. It needs a substrate with at least a degree of porosity, and every modern paint I've tried to cover simply doesn't offer that.
So, from personal experience, the short answer is 'No'!

 

[andrew gayton]

The good news is that the material comes off the brick quite easily by the looks of it, and the paint is stuck to the material so that comes off too. The brick beneath needs attention, pointing etc, but its not in the state I thought it would be.

Anyone any idea what that could be?

Yes, it is a product used in the 60's and 70's - like a reinforced tar paper. the reinforcment is very strong. used to 'weatherproof' and 'repair' walling. it was made by s****ex and unsuitable for soild walls for obvious reasons. remove it. the tar from moo is probably coal tar.

 

[Nemesis]

The good news is you have returned!

Yay!! Thank you.

Ev xxx

 

[andrew gayton]

nemesis - thank-you!... lets see what we can do....xx