Should I not be expecting a bit more from this rendering?

[SmileyDan]

A house I have moved into. The render is just over a decade old. Repainted about three years ago. Cement render (I assume) on a cavity wall, built in early 2000s and rendered immediately.

Should it be showing cracks like this? Not massive cracks, but still...

 

[roughcaster]

Give them a tap with your knuckles Dan to see if the cracked areas sound hollow, especially the long vertical crack going up the corner. Cracking like that shouldn't happen without a reason. Were they there when it was re-painted 3 years ago? Another thing to check out is the rust coming through on the corner?????

 

[SmileyDan]

Thanks. Yeah, it doesn't come through in the photo, but rust is coming through.

If you tap the cracks they don't sound hollow (there are other areas which do, but not the ones I posted the pictures of) but they do sound different to around. Again, this doesn't come through in the picture but the texture looks different from different angles. Could be previous repair?

I don't know if the cracks were there when it was painted as we weren't in the house then.

 

[roughcaster]

It might look worse than what it is, and it's certainly not going to fall off anytime soon, but if i were you, i'd have a chat with a reputable local plasterer/ builder for an opinion. The rust on the corners is certainly worth looking at.

 

[ree]

Good call ref the rusting corner bead - obviously not a plastic or SS corner bead.

Wonder why it was rendered 10 yrs ago?

Why the French drain around the house?

Was it re-painted 3 yrs ago or simply painted and crack filled just before the sale?

The frames are not set back the recommended 75mm - hopefully not an issue if no interior damp signs.

Any history of remedial work on the walls?

Does it have cavity insulation?

 

[SmileyDan]

Good call ref the rusting corner bead - obviously not a plastic or SS corner bead.

What does it mean to have a rusting corner bead? Water ingress causing the rust?

Wonder why it was rendered 10 yrs ago?

The rest of the house was already rendered when this extension was added, so it was to tie in.

Why the French drain around the house?

Don't know, why would you have a french drain? It is around the entire house.

Was it re-painted 3 yrs ago or simply painted and crack filled just before the sale?

I don't understand the distinction... I don't know if it was crack filled, but the entire house was re-painted.

The frames are not set back the recommended 75mm - hopefully not an issue if no interior damp signs.

No interior damp signs.

Any history of remedial work on the walls?

Not that I know of. There are cracks elsewhere, but no large ones.

Does it have cavity insulation?

Yes, this was built in early 00s. It's fibrous - I know because I was in the eaves at the weekend and the cavity appears to be open.

 

[SmileyDan]

Hey Joe, I'm gravelld from the GBF

 

[ree]

OP,
What does your last post mean? The 12:00 PM 15/09/2015 post.

 

[SmileyDan]

Errr, well that's awkward. There was another reply in there from someone I recognised on the Green Building Forum (GBF). It's gone now! Hope that explains it.


<Moderators note>
An abusive post was removed

 

[ree]

Moisture causes rust and the metal corner bead swells.

Non rendered houses are often later rendered because of defects that occur.

French drains are often installed to divert damaging water away from the walls and floors.

Sellers often tart up their damaged or cracked properties just before a sale. Done 3yrs ago would indicate routine maintenance.

"Cracks elsewhere" might indicate excessive thermal movement?

"fibrous insulation" is the worst kind of blown cavity insulation but if its become sodden it usually shows on interior walls.

 

[SmileyDan]

Maybe there was once a problem, which motivated the original decision to render. The house was built in the 50s. We have a picture of it in the 70s (I think) and it is still non rendered. Now, only about 20% of the original perimeter is exposed following multiple extensions and so the French drains don't really cover much of the original wall. I was wrong - they are not around 100% of the outside, probably about 85%.

Thermal movement - do you mean movement in the ground caused by thermal changes? Or do you mean movement in the fabric of the house caused by temperature and maybe moisture change?

Would lime render not crack in this way, or would a different cement based product be better? Like the newer acrylic renders etc?

Yep, agree about the CWI, much prefer EPS.

 

[ree]

Thermal movement in the fabric. Typically, people have to live with it as far as i know.

Advice on best and most modern techniques and materials will have to come from the guys on here who are specialists in rendering.

 

[SmileyDan]

Interesting. I wonder if the rust and the cracks are related. I didn't mention this is a fairly exposed SW wall (the pic where most of the cracks are).