ᐅ Renovating Exterior/Retaining Wall (Cracking Plaster / Wall Capping)
Created on: 8 May 2020 17:41
A
AnghiHello everyone,
When we built our house six years ago, a low retaining wall was constructed along our driveway next to the adjoining sidewalk. The wall was plastered white at the time, and we cut granite slabs for the wall cap from leftovers of the entrance platform. According to building regulations, we had to leave a 10cm (4 inch) gap between the wall and the sidewalk, which created a "dirt gap." This gap was simply lined with some dimpled membrane, and I tried to plant a few cushion plants in it. Unfortunately, the plaster started to crumble after a short time. We reported this to the landscaper, who reapplied the plaster, but that didn’t hold either. Furthermore, the wall capping stones soon became loose. The landscaping company no longer exists...
This is what our wall looks like now:
For better understanding: the front part of the wall (about 7 meters (23 feet)) is exposed, while the rear part has had a carport built around two years ago. Interestingly, the plaster only crumbles on the front part; where the carport is, the plaster is still intact. Luckily, because I can’t access the wall there anymore.
There is a staircase running on the backside of the carport, where a section of the wall is also visible, and some of the plaster is starting to crumble there as well.
I am now looking for advice on how to best repair the damage and prevent future problems.
Lots of questions, but I would really like to resolve this annoying issue since I see this "shame wall" every day, and it does not fit my idea of a new build...
Thank you very much in advance for all your helpful and detailed tips!
Anghi
When we built our house six years ago, a low retaining wall was constructed along our driveway next to the adjoining sidewalk. The wall was plastered white at the time, and we cut granite slabs for the wall cap from leftovers of the entrance platform. According to building regulations, we had to leave a 10cm (4 inch) gap between the wall and the sidewalk, which created a "dirt gap." This gap was simply lined with some dimpled membrane, and I tried to plant a few cushion plants in it. Unfortunately, the plaster started to crumble after a short time. We reported this to the landscaper, who reapplied the plaster, but that didn’t hold either. Furthermore, the wall capping stones soon became loose. The landscaping company no longer exists...
This is what our wall looks like now:
For better understanding: the front part of the wall (about 7 meters (23 feet)) is exposed, while the rear part has had a carport built around two years ago. Interestingly, the plaster only crumbles on the front part; where the carport is, the plaster is still intact. Luckily, because I can’t access the wall there anymore.
There is a staircase running on the backside of the carport, where a section of the wall is also visible, and some of the plaster is starting to crumble there as well.
I am now looking for advice on how to best repair the damage and prevent future problems.
- How can I better protect the wall from moisture?
- Do I need to replace or renew the wall capping?
- Should I waterproof or prepare the wall underneath the capping before installing new stones?
- What should I do with the sparsely planted "dirt gap"? Should I fill it with concrete? I find it more pleasant with plants, but weeds grow there and cigarette butts and candy wrappers often end up in the gap – so it’s not ideal.
- How can I best repair or renew the plaster?
- Does it make sense to apply new plaster again, or would it be better to cover the exposed wall area with facing bricks or cladding?
- Do I need a special base or adhesive with moisture protection for the facing bricks or cladding?
- (And a probably silly question: How can I cleanly separate the old plaster where the carport begins?)
Lots of questions, but I would really like to resolve this annoying issue since I see this "shame wall" every day, and it does not fit my idea of a new build...
Thank you very much in advance for all your helpful and detailed tips!
Anghi
Well, the wall is probably damp. If the moisture comes from below, the foundation was either improperly constructed and/or no waterproofing against the ground was applied. Try searching for "horizontal damp proof course." The options are either (expensive) restoration or complete demolition and rebuilding.
It would be “better” if only the plaster was poorly applied. In that case, a demolition hammer with a chisel can help to remove the old plaster (cut straight to the carport with a cutoff wheel and then chisel, possibly by hand). However, the affected coping stones suggest that the entire wall is damp :-/ Or they might just happen to be poorly made and have not withstood frost.
It would be “better” if only the plaster was poorly applied. In that case, a demolition hammer with a chisel can help to remove the old plaster (cut straight to the carport with a cutoff wheel and then chisel, possibly by hand). However, the affected coping stones suggest that the entire wall is damp :-/ Or they might just happen to be poorly made and have not withstood frost.
Hello again, and sorry for not getting back to you sooner. Thanks also for your assessments. In the meantime, a landscaper came by to take a look at the wall and basically confirmed TomTom79’s suspicion: the main cause seems to be the unsuitable and poorly installed wall capping stones. However, he advised us to have a plasterer take a closer look as well—building the wall and applying plaster are two different trades (last time, the landscaper did both himself). We now have a quote for new wall capping stones and will contact a plasterer regarding the rendering. I originally wanted to do the plastering myself, but I’m not really confident enough to tackle it...
I realized myself that we ended up with a poor-quality contractor. Unfortunately, that insight doesn’t help much. This is a new development area, meaning that practically everyone is building at the same time and all tradespeople are fully booked. It’s lucky just to find a landscaper with an available appointment. And if you get one recommended by a neighbor, you’d expect that person to know their trade well.
Tearing down the wall is out of the question. As far as the horizontal damp-proof course is concerned, I’m confident that it was done correctly. The "bare" wall was/is perfect. The membrane on the back (in my planting trench) was not installed properly, the capping stones are poor quality (not cut cleanly, no drip groove, not properly adhered), and the plastering itself was not done properly. However, these are all flaws that should be fixable afterwards.
If I had to tear down the wall, I would also have to remove the carport, partially repave the driveway, risk damaging the adjoining sidewalk (city property) during demolition, and so on... Sorry, but that is far too risky, complicated, and expensive—just because the plaster is crumbling. At the moment, this is primarily a cosmetic issue (which I was planning to address with a suitable workaround). There is no indication that the wall can no longer serve its purpose—namely, supporting the terrain—in the foreseeable future. That’s why I’d prefer to keep things in perspective...
Still, thanks for all the tips and assessments!
I realized myself that we ended up with a poor-quality contractor. Unfortunately, that insight doesn’t help much. This is a new development area, meaning that practically everyone is building at the same time and all tradespeople are fully booked. It’s lucky just to find a landscaper with an available appointment. And if you get one recommended by a neighbor, you’d expect that person to know their trade well.
Tearing down the wall is out of the question. As far as the horizontal damp-proof course is concerned, I’m confident that it was done correctly. The "bare" wall was/is perfect. The membrane on the back (in my planting trench) was not installed properly, the capping stones are poor quality (not cut cleanly, no drip groove, not properly adhered), and the plastering itself was not done properly. However, these are all flaws that should be fixable afterwards.
If I had to tear down the wall, I would also have to remove the carport, partially repave the driveway, risk damaging the adjoining sidewalk (city property) during demolition, and so on... Sorry, but that is far too risky, complicated, and expensive—just because the plaster is crumbling. At the moment, this is primarily a cosmetic issue (which I was planning to address with a suitable workaround). There is no indication that the wall can no longer serve its purpose—namely, supporting the terrain—in the foreseeable future. That’s why I’d prefer to keep things in perspective...
Still, thanks for all the tips and assessments!
What kind of cover plates are you planning to use now? I find most of them quite unattractive, so it will probably be natural stone, despite the cost. If the plaster problem isn’t easy to fix but the wall is structurally sound, you could also consider cladding with boards. That would also match the carport.
Similar topics