Type of render....

[LesDavidson]

Hi,

I'm planning to have the pebbledash on my 1930's semi detached house painted with masonry paint. I've read various articles over the years that this isn't a good idea as can stop the wall from breathing and cause damp.

I've recently been told that if the pebbledash render is cement based (rather than lime based) that it is impermeable anyway and not an issue.

The house has also been re-dashed at some point in the past 10 years on top of the original pebbledash.

From what I've been able to find on the Internet, it would seem highly likely that the render is cement based.

My question is, is there an easy way of confirming?

Les

 

[huddsspread]

take a photo and put it on. But i have been around 1930s pebble dash, and it is harder than superman. If its been done again, likely hood is its cement.

Get pics on first though.

 

[peaps]

It was traditionally lime based pebble dash and if it is lime based construction you would be best advised to use lime.

Cement will seal the wall and is too ridged to allow your house to move with the seasons. This is a common problem when cement based renders are used on lime based constructions, it crack, hollows and falls off the wall.

 

[LesDavidson]

The first two pictures are of the new pebbledash on my house, the last is the original underlying pebbledash (taken from neighbouring property which has not been re-dashed).

Rgds,

Les

 

[LesDavidson]

And with the photos...

New Pebbledash 1

• LesDavidson
• 14 Mar 2012
• 1

New Pebbledash 2

• LesDavidson
• 14 Mar 2012
• 1

Original Underlying Pebbledash

• LesDavidson
• 14 Mar 2012
• 1

 

[LesDavidson]

Hi, Can anyone help me with this query?

 

[peaps]

It would be a guess.

 

[huddsspread]

If it was my house, i would just paint it. Will take a good few coats to get in every tiny little hole.

 

[peaps]

If it was my house, i would just paint it. Will take a good few coats to get in every tiny little hole.

If it's lime based then it would need to be a breathable paint. It's hard to tell what it is from a picture.

 

[huddsspread]

If you by breathable paint then you will be fine. If it is lime ( seems a bit red for me, but that dont mean its not in there) or if its not, cover it in the breathable paint and it wont matter. As i said earlier, painting thats a nightmare, so many tiny little bits to get into...good luck

 

[peaps]

If you by breathable paint then you will be fine. If it is lime ( seems a bit red for me, but that dont mean its not in there) or if its not, cover it in the breathable paint and it wont matter. As i said earlier, painting thats a nightmare, so many tiny little bits to get into...good luck

The red will come from the sand used, if the sand was yellow the mortar would be whitish.