Hello!
Here comes my debut on this excellent forum.
I have built a retaining wall (50-60 cm high) and plan to plaster it. It's about 50 m2 of surface area.
All the work was done before I joined this forum, so there's no point in asking if I did it right. Anyway, I have cast a footing (6-8 cm) with reinforcement under the wall to prevent settling. Inside the wall, there is drainage and a platonmatta to reduce the risk of moisture penetrating the Lecablocken. Additionally, I have reinforced all the posts to strengthen the corners.
Pictures:
http://www.sbbk.se/team_gallery.php?category=328
Now, my question is which type of plastering method I should use. My idea is to apply plaster mortar B or C by hand with the help of support ribs and cut to a smooth surface, and on this, apply "ädelputs" or "sprita" by hand. Then, I'll paint with some silicone-based paint.
I haven't thought about applying a base plaster because everyone says the adhesion is very good in Leca blocks.
Am I thinking correctly?
Here comes my debut on this excellent forum.
I have built a retaining wall (50-60 cm high) and plan to plaster it. It's about 50 m2 of surface area.
All the work was done before I joined this forum, so there's no point in asking if I did it right. Anyway, I have cast a footing (6-8 cm) with reinforcement under the wall to prevent settling. Inside the wall, there is drainage and a platonmatta to reduce the risk of moisture penetrating the Lecablocken. Additionally, I have reinforced all the posts to strengthen the corners.
Pictures:
http://www.sbbk.se/team_gallery.php?category=328
Now, my question is which type of plastering method I should use. My idea is to apply plaster mortar B or C by hand with the help of support ribs and cut to a smooth surface, and on this, apply "ädelputs" or "sprita" by hand. Then, I'll paint with some silicone-based paint.
I haven't thought about applying a base plaster because everyone says the adhesion is very good in Leca blocks.
Am I thinking correctly?
Thank you for your response, Tompa!
I would like to ask the following follow-up question since I've never worked with plaster before.
Do you buy "regular" cement, lime, and fine sand and then mix them together? That sounds reasonable to me, but I have no idea how to maintain the proportions to get durable plaster. Several people have mentioned that you should use "betongputs" to get a hard and good surface, so I believe in your suggestion, as long as I learn how to mix the mortar. Maybe it's stated on some product declaration/information sheet from the manufacturers?
I've also been advised to texture the surface with a wet brush, so that seems like a sensible way to go. First and foremost, it's about getting the mortar together.
Thanks for now.
I would like to ask the following follow-up question since I've never worked with plaster before.
Do you buy "regular" cement, lime, and fine sand and then mix them together? That sounds reasonable to me, but I have no idea how to maintain the proportions to get durable plaster. Several people have mentioned that you should use "betongputs" to get a hard and good surface, so I believe in your suggestion, as long as I learn how to mix the mortar. Maybe it's stated on some product declaration/information sheet from the manufacturers?
I've also been advised to texture the surface with a wet brush, so that seems like a sensible way to go. First and foremost, it's about getting the mortar together.
Thanks for now.
Regarding concrete plaster and other ready-made products, I have never used them and do not know what they actually are. But my suspicion is that they are regular cement, lime, and sand pre-mixed, and this at an enormous overprice. But as I said, I know nothing about them.
However, I have cast, laid bricks, and plastered quite a bit without needing these ready-made products. Regarding mixing ratios for plastering, I need to check, it's been a while since I last plastered, I recall it being 1 part cement, 4 parts fine sand, and ¼ lime. However, I'm not certain and will get back to you after checking my "recipe book," otherwise, maybe someone knows the proportions by heart.
Regarding slurry, I haven't tried it, even though I know many recommend it. My own experience is that if the plaster is allowed to cure properly before I use silicate paint, the grid pattern is not visible. Another advantage of slurry is said to be that the plaster adheres better, but so far I have not experienced my plaster detaching. However, you must throw on the plaster so that it penetrates the pores of the leca. It's also important to keep the plaster moist when it starts curing, as leca absorbs some of the water, which would degrade the plaster.
Tompa
However, I have cast, laid bricks, and plastered quite a bit without needing these ready-made products. Regarding mixing ratios for plastering, I need to check, it's been a while since I last plastered, I recall it being 1 part cement, 4 parts fine sand, and ¼ lime. However, I'm not certain and will get back to you after checking my "recipe book," otherwise, maybe someone knows the proportions by heart.
Regarding slurry, I haven't tried it, even though I know many recommend it. My own experience is that if the plaster is allowed to cure properly before I use silicate paint, the grid pattern is not visible. Another advantage of slurry is said to be that the plaster adheres better, but so far I have not experienced my plaster detaching. However, you must throw on the plaster so that it penetrates the pores of the leca. It's also important to keep the plaster moist when it starts curing, as leca absorbs some of the water, which would degrade the plaster.
Tompa
I have come to the following conclusion.
Given my circumstances, I will use dry mortar. More expensive, but considering it's "only" about 50 m2, it will still only cost around 3,000 SEK.
I'm skipping the base coat since it's just a retaining wall that we'll paint later. Therefore, I'm not worried about the "grid pattern" that might emerge. Leca should have sufficient adhesion capacity nonetheless.
I feel I have two choices.
------------------------------
1. Single-layer plastering.
The choice is Plaster Mortar B, which I apply by hand and smooth out with a leveling board.
Then, I use a float and create texture with a stiff brush or similar tool.
Afterwards, I paint the surface with appropriate paint.
-------------------------------
2. Two-layer plastering.
I base-coat with Plaster Mortar B and smooth out with a leveling board.
Once it has dried a little, I apply a new layer with splatter or spray plaster to create an uneven texture on the wall.
Then, I spray paint the textured surface.
---------------------------
I make the plaster laths from rebar, which I "stick" with concrete. The alternative is to cut molding from form plywood and nail it in place, but I find the rebar method requires less filling when they're removed.
Regarding Tompa's advice on Concrete, Lime, and Sand, I've now learned that this is exactly what's in the dry mortars. The differences between classes A, B, and C are in the proportions. B seems to be the proportion Tompa suggested, and both Finja and Maxit recommend it. Overpricing is probably true, but as I said, my lack of experience in the trade and the amount needed make me opt for dry mortar.
I should also make sure to sufficiently water it afterward, according to Tompa's advice.
The only concern I have right now is how to apply the texture, i.e., "splatter" the surface layer. I'm not afraid to try new methods (meaning I have no method right now :-/), and a coarse brush combined with a flick of the wrist is what seems most feasible. Anyone have a tip for this?
Given my circumstances, I will use dry mortar. More expensive, but considering it's "only" about 50 m2, it will still only cost around 3,000 SEK.
I'm skipping the base coat since it's just a retaining wall that we'll paint later. Therefore, I'm not worried about the "grid pattern" that might emerge. Leca should have sufficient adhesion capacity nonetheless.
I feel I have two choices.
------------------------------
1. Single-layer plastering.
The choice is Plaster Mortar B, which I apply by hand and smooth out with a leveling board.
Then, I use a float and create texture with a stiff brush or similar tool.
Afterwards, I paint the surface with appropriate paint.
-------------------------------
2. Two-layer plastering.
I base-coat with Plaster Mortar B and smooth out with a leveling board.
Once it has dried a little, I apply a new layer with splatter or spray plaster to create an uneven texture on the wall.
Then, I spray paint the textured surface.
---------------------------
I make the plaster laths from rebar, which I "stick" with concrete. The alternative is to cut molding from form plywood and nail it in place, but I find the rebar method requires less filling when they're removed.
Regarding Tompa's advice on Concrete, Lime, and Sand, I've now learned that this is exactly what's in the dry mortars. The differences between classes A, B, and C are in the proportions. B seems to be the proportion Tompa suggested, and both Finja and Maxit recommend it. Overpricing is probably true, but as I said, my lack of experience in the trade and the amount needed make me opt for dry mortar.
I should also make sure to sufficiently water it afterward, according to Tompa's advice.
The only concern I have right now is how to apply the texture, i.e., "splatter" the surface layer. I'm not afraid to try new methods (meaning I have no method right now :-/), and a coarse brush combined with a flick of the wrist is what seems most feasible. Anyone have a tip for this?
Considering the amount, I think you are making the right choice.
Regarding creating a surface texture, wait until it has started to set a bit, then take a broad and wide stiff brush that you dip in water to keep it wet. You don't need to use any flick or pressure here if the brush has the right stiffness. A regular paintbrush is too soft, and a piassavabroom is too stiff. If the mix has set just right, the water in the brush will now brush the surface to make it slightly grainy, and if the finish is not too uneven, you'll get a surface that looks homogeneous and nice.
Feel free to test on a loose piece of leca so you know how much it should set before brushing. Too early, and you'll brush away the plaster, and too late, and it won't have any effect.
Tompa
Regarding creating a surface texture, wait until it has started to set a bit, then take a broad and wide stiff brush that you dip in water to keep it wet. You don't need to use any flick or pressure here if the brush has the right stiffness. A regular paintbrush is too soft, and a piassavabroom is too stiff. If the mix has set just right, the water in the brush will now brush the surface to make it slightly grainy, and if the finish is not too uneven, you'll get a surface that looks homogeneous and nice.
Feel free to test on a loose piece of leca so you know how much it should set before brushing. Too early, and you'll brush away the plaster, and too late, and it won't have any effect.
Tompa
Hi Tompa!
I've started now.
I've been experimenting, but since I'm working alone, it's quite a hassle to mix, polish, remove, and replace distance slats, fill them, and then remove the fillings at the right time... PHEW!
I made distance slats out of form plywood instead of rebar. The rebar was too difficult to secure. I have a good table saw, so I could make exact distances for the plaster.
I've been removing with a scrubbing brush. First, I remove when it's just a little hard, and then I do it again when it's halfway cured. I use the same scrubbing brush, but it becomes a perfect mix of hard and soft removal when I use the scrubbing brush.
When the plaster is soft, plaster sticks to the brush, and it scrapes hard on the plaster. Sort of like a float, but a bit "softer". When the plaster has cured more, plaster doesn't stick to the brush, and its soft bristles just bring out the small stones in the plaster. This way, I get a good alternative for the surface if my wife is satisfied with it
Otherwise, I've been eyeing a spray plaster machine that costs about 700 SEK, but since I initially had a quote of 20,000 (?!) from a mason, there's still plenty of budget left in the project. ;D
We'll see what comes of it. I will, of course, show some pictures when I'm done.
I've started now.
I've been experimenting, but since I'm working alone, it's quite a hassle to mix, polish, remove, and replace distance slats, fill them, and then remove the fillings at the right time... PHEW!
I made distance slats out of form plywood instead of rebar. The rebar was too difficult to secure. I have a good table saw, so I could make exact distances for the plaster.
I've been removing with a scrubbing brush. First, I remove when it's just a little hard, and then I do it again when it's halfway cured. I use the same scrubbing brush, but it becomes a perfect mix of hard and soft removal when I use the scrubbing brush.
When the plaster is soft, plaster sticks to the brush, and it scrapes hard on the plaster. Sort of like a float, but a bit "softer". When the plaster has cured more, plaster doesn't stick to the brush, and its soft bristles just bring out the small stones in the plaster. This way, I get a good alternative for the surface if my wife is satisfied with it
Otherwise, I've been eyeing a spray plaster machine that costs about 700 SEK, but since I initially had a quote of 20,000 (?!) from a mason, there's still plenty of budget left in the project. ;D
We'll see what comes of it. I will, of course, show some pictures when I'm done.
Hello Peter!
In reality, it's only afterwards that you know if it was worth doing the job. After working 15-16 hours straight from Saturday to Monday, I was like a zombie on Tuesday at work. Despite that, I don't regret daring to try.
If you are going to do smaller and more manageable projects, it's definitely worth the effort. I've found that the material cost for the plaster (including 9 meshed posts) amounts to about 2,500 kronor if you settle for a hand-brushed or broomed surface that is not painted or colored. The surface area is about 40-45 m2. I've used dry mortar which is much more expensive than mixing cement, lime, and sand yourself.
Since I've done a thorough job with the concrete base under the wall and reinforced leca blocks, the wall is now perfectly straight with a nice, slightly roughened surface. Neighbors stop their cars and give encouraging remarks about the result, so it seems more than just me think it looks good.
One of the challenges so far has been that I'm working alone, which means I can't be as efficient as I would like. I quickly learned how to throw up the plaster, and since I have dry mortar, it's just a matter of adding the right amount of water to get it sticky enough. The difficulty is the corners of the posts, which easily become too wet and porous and come loose. For flat surfaces, like a house, one should be able to streamline the way of applying the plaster by pressing it on with a float.
Pictures will come eventually.
In reality, it's only afterwards that you know if it was worth doing the job. After working 15-16 hours straight from Saturday to Monday, I was like a zombie on Tuesday at work
. Despite that, I don't regret daring to try.If you are going to do smaller and more manageable projects, it's definitely worth the effort. I've found that the material cost for the plaster (including 9 meshed posts) amounts to about 2,500 kronor if you settle for a hand-brushed or broomed surface that is not painted or colored. The surface area is about 40-45 m2. I've used dry mortar which is much more expensive than mixing cement, lime, and sand yourself.
Since I've done a thorough job with the concrete base under the wall and reinforced leca blocks, the wall is now perfectly straight with a nice, slightly roughened surface. Neighbors stop their cars and give encouraging remarks about the result, so it seems more than just me think it looks good.
One of the challenges so far has been that I'm working alone, which means I can't be as efficient as I would like. I quickly learned how to throw up the plaster, and since I have dry mortar, it's just a matter of adding the right amount of water to get it sticky enough. The difficulty is the corners of the posts, which easily become too wet and porous and come loose. For flat surfaces, like a house, one should be able to streamline the way of applying the plaster by pressing it on with a float.
Pictures will come eventually.
Fun that it turned out well, Shrek.
The corners are easiest made by nailing a board to the gable that sticks out for support. Then apply the plaster to one side. Once it has set, remove the board and plaster the remaining side. When I plaster, I actually don't use a board to smooth the surface completely, but instead use a suitable wooden block to smooth it freehand. This makes the surface not perfectly flat but gives it a sense of craftsmanship, rather than prefabricated elements. After brushing, you have to stand close to see this. But I think it gives the wall more life and shows that someone stood there and sweated. Additionally, it's faster.
If anyone is inspired to make their own wall, I would have made the foundation a bit thicker if possible. About 20cm would be preferable, depending a bit on what the ground beneath looks like.
Tompa
The corners are easiest made by nailing a board to the gable that sticks out for support. Then apply the plaster to one side. Once it has set, remove the board and plaster the remaining side. When I plaster, I actually don't use a board to smooth the surface completely, but instead use a suitable wooden block to smooth it freehand. This makes the surface not perfectly flat but gives it a sense of craftsmanship, rather than prefabricated elements. After brushing, you have to stand close to see this. But I think it gives the wall more life and shows that someone stood there and sweated. Additionally, it's faster.
If anyone is inspired to make their own wall, I would have made the foundation a bit thicker if possible. About 20cm would be preferable, depending a bit on what the ground beneath looks like.
Tompa
Thanks for the corner tip. I had heard about this method before, but by then I had already made a corner that I was satisfied with without support, so I continued with that. My method was probably a bit more complicated, but it allowed me to work continuously.
I agree with you that there was an opportunity to make it look more handmade, but since I have the "symmetry devil" in me, it turned out straight and neat everywhere. Maybe a bit boring, but when you're doing it for the first time, you’d rather make it straight and neat than add too much of an artistic touch and then realize it doesn't look good. The "prefabricated" look, however, fits very well with the straight lines of the wall.
Now I'm facing the next consideration.
Since in the beginning, I removed the spacers only when the mortar dried, I've got ugly marks in the plaster from these, despite being very careful to fill and make it look good. After about 1/4, I removed the spacers "on the fly," and the result was excellent. Now I have 25% ugly wall and 75% nice wall.
My options are to plaster 5-7 mm on the spots where I have ugly marks and be satisfied with the surface as it is, or apply noble plaster. Since my wife wants a more textured surface, I have ordered a Splatter Plaster Machine and will try it on some concrete blocks to see how it feels to use it. Everything could also remain as it is, and then we'll paint it with a good plaster paint.
Anyone with experience working with a Splatter Plaster Machine and what to think about?
I agree with you that there was an opportunity to make it look more handmade, but since I have the "symmetry devil" in me, it turned out straight and neat everywhere. Maybe a bit boring, but when you're doing it for the first time, you’d rather make it straight and neat than add too much of an artistic touch and then realize it doesn't look good. The "prefabricated" look, however, fits very well with the straight lines of the wall.
Now I'm facing the next consideration.
Since in the beginning, I removed the spacers only when the mortar dried, I've got ugly marks in the plaster from these, despite being very careful to fill and make it look good. After about 1/4, I removed the spacers "on the fly," and the result was excellent. Now I have 25% ugly wall and 75% nice wall.
My options are to plaster 5-7 mm on the spots where I have ugly marks and be satisfied with the surface as it is, or apply noble plaster. Since my wife wants a more textured surface, I have ordered a Splatter Plaster Machine and will try it on some concrete blocks to see how it feels to use it. Everything could also remain as it is, and then we'll paint it with a good plaster paint.
Anyone with experience working with a Splatter Plaster Machine and what to think about?
The plaster takes a couple of days to set and lightens in color during that time. It's not uncommon for there to be small color differences. Initially, it appears as large differences, but after about a week, the differences are usually very small. In your case, I would keep the wall moist and wait a couple of days until it has fully set. Then the color should be able to cover any remaining differences. Personally, I am fond of silicate paint on plaster (lime is also cheap and good, but labor-intensive. Also requires more maintenance). Regarding other surface treatments, I have no experience.
After rereading, perhaps I misunderstood you. Are you experiencing a level difference or cracks where the battens were? If so, I don't have a clear-cut solution, but maybe you can apply a very thin slurry. However, the risk is high that it will flake off in pieces, and it won't be attractive.
Tompa
After rereading, perhaps I misunderstood you. Are you experiencing a level difference or cracks where the battens were? If so, I don't have a clear-cut solution, but maybe you can apply a very thin slurry. However, the risk is high that it will flake off in pieces, and it won't be attractive.
Tompa
Hello to those interested in how my wall is progressing.
We have now decided on how to proceed.
We will apply a layer of rendering plaster, surface-, or noble plaster (Beijers is helping us with what we should use) which we will apply with a Stänkputsapparat.
We have chosen a pigmented mortar with a standard color that goes in the same tone as the light green on our house.
As I said, I have never worked with a Stänkputsapparat before, but I've never built a wall before either...
With the Stänkputsapparat and pigmented mortar, I expect to fill in the irregularities and color differences that currently exist.
What I can conclude is that by applying splash plaster, you get a bit more texture (we have looked at samples) than what we have brushed out. The advantage of "just" brushing out a texture and then painting is that you skip the step of surface plastering (and save some money), but with pigmented mortar, we avoid painting. However, I believe the result of our choice will be better than the current brushed-out texture.
Looking forward to starting to practice with the Stänkputsapparat! ;D
We have now decided on how to proceed.
We will apply a layer of rendering plaster, surface-, or noble plaster (Beijers is helping us with what we should use) which we will apply with a Stänkputsapparat.
We have chosen a pigmented mortar with a standard color that goes in the same tone as the light green on our house.
As I said, I have never worked with a Stänkputsapparat before, but I've never built a wall before either...
With the Stänkputsapparat and pigmented mortar, I expect to fill in the irregularities and color differences that currently exist.
What I can conclude is that by applying splash plaster, you get a bit more texture (we have looked at samples) than what we have brushed out. The advantage of "just" brushing out a texture and then painting is that you skip the step of surface plastering (and save some money), but with pigmented mortar, we avoid painting. However, I believe the result of our choice will be better than the current brushed-out texture.
Looking forward to starting to practice with the Stänkputsapparat! ;D