We are planning to remodel the bathroom on the upper floor in a light concrete house, including the rerouting of drainage pipes. The intermediate floor consists of light concrete slab elements, and I wonder if it's true that you cannot cut larger holes in the elements except at the joints?
/chillichi
/chillichi
How large holes should you make? How wide are your elements?
A 110mm hole is not a problem, provided the element is not in poor condition, and no other holes are made nearby. Even in adjacent elements.
I assume you will cast a layer of leveling compound on top afterwards? That will help with weight distribution, and if you're going to have a bathtub, you should consider the placement and weight distribution as well.
A 110mm hole is not a problem, provided the element is not in poor condition, and no other holes are made nearby. Even in adjacent elements.
I assume you will cast a layer of leveling compound on top afterwards? That will help with weight distribution, and if you're going to have a bathtub, you should consider the placement and weight distribution as well.
A little more information:
The house is two stories with a basement.
We want to build a new bathroom on the upper floor with a toilet, shower, and washbasin.
We actually want to extend a 110mm sewer pipe from the basement and then cast connections for the toilet, floor drain, and washbasin in the floor joists to avoid hanging the horizontal pipes in the living room ceiling.
The elements are 60cm wide, Siporex from 1975.
Yes, we will apply leveling compound and lay tiles, and no holes have previously been made in the elements that are affected.
The house is two stories with a basement.
We want to build a new bathroom on the upper floor with a toilet, shower, and washbasin.
We actually want to extend a 110mm sewer pipe from the basement and then cast connections for the toilet, floor drain, and washbasin in the floor joists to avoid hanging the horizontal pipes in the living room ceiling.
The elements are 60cm wide, Siporex from 1975.
Yes, we will apply leveling compound and lay tiles, and no holes have previously been made in the elements that are affected.
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Corre: I interpret you as suggesting that it may be OK to make holes in the floor slab, but how do you do it practically?
I'm thinking about getting through the reinforcement.
Is it also possible to create "trenches" to cast pipes without securing against surrounding elements?
I'm thinking about getting through the reinforcement.
Is it also possible to create "trenches" to cast pipes without securing against surrounding elements?
You can make holes, but you shouldn't make so many that you have to cut more than one reinforcing bar per element. The easiest way is with a hammer drill and a template, for example, a plywood board with a cut 130mm hole that you drill through and then knock out with a hammer and chisel. You should not make grooves in the lightweight concrete, as it may weaken it too much.
How much of the upper floor does this ceiling support? Is there a load-bearing wall in the middle that takes the load? That can determine what you're willing to do.
How much of the upper floor does this ceiling support? Is there a load-bearing wall in the middle that takes the load? That can determine what you're willing to do.
Aha, so we should be able to pull up the drainage pipes from below, even outside the element joints. However, is it not recommended to also cut a groove in the floor upstairs to connect, for example, 75 mm pipes from the floor drain and WC? Instead, should we arrange this from below?
Yes, there is a hjärtvägg (partially a beam), which is asymmetrically placed. The house is 7m wide, the hjärtvägg runs in the length of the house about 2.5m in from one long side. The floor elements run perpendicular to the hjärtvägg. So, there is a span of 2.5m, then a span of 4.5m. We are planning the new bathroom over the shorter span.
I can upload a plan sketch if it's unclear what I mean.
Yes, there is a hjärtvägg (partially a beam), which is asymmetrically placed. The house is 7m wide, the hjärtvägg runs in the length of the house about 2.5m in from one long side. The floor elements run perpendicular to the hjärtvägg. So, there is a span of 2.5m, then a span of 4.5m. We are planning the new bathroom over the shorter span.
I can upload a plan sketch if it's unclear what I mean.
How high do you have to the finished floor then? Should be at least 100mm if you're going to fit the floor drain.
Then you can accommodate 75mm pipes for the shower and 50mm for the sink if you cast it into the slab.
You'll need to calculate the elements a bit too, the reinforcement is usually in 3 or 4 rows. So for example, 1/4 in comes first, and 2/4 second for example, then you can time 110mm to the toilet at a middle space so you don't need to cut the reinforcement.
Then you can accommodate 75mm pipes for the shower and 50mm for the sink if you cast it into the slab.
You'll need to calculate the elements a bit too, the reinforcement is usually in 3 or 4 rows. So for example, 1/4 in comes first, and 2/4 second for example, then you can time 110mm to the toilet at a middle space so you don't need to cut the reinforcement.
Is it necessary to place the floor drain on top of the existing floor and raise the floor by 10cm?
We only have 240 in ceiling height, so it would be a shame to lose that much.
For the floor drain, it is a better option - if possible - to run the pipe from the upper floor directly down to the basement rather than raising the floor (it fits quite well with the interior walls on the ground floor).
Do you have any tips on how to locate the reinforcement in the elements?
We only have 240 in ceiling height, so it would be a shame to lose that much.
For the floor drain, it is a better option - if possible - to run the pipe from the upper floor directly down to the basement rather than raising the floor (it fits quite well with the interior walls on the ground floor).
Do you have any tips on how to locate the reinforcement in the elements?
Wow, do you have the floor directly on aerated concrete?
How thick are those elements?
When I've previously seen aerated concrete in houses, the other floors have been insulated, framed floors with a height of around 90-120mm, often with rough plywood panels. Then you place your floor surface on that.
If you're making a bathroom, for instance, you have 120mm to lay pipes, pour, and level with self-leveling compound.
Now, I'm not a builder or constructor, and I've seen maybe 2-3 floor constructions with aerated concrete. There are surely lots of ways to use those elements.
How thick are those elements?
When I've previously seen aerated concrete in houses, the other floors have been insulated, framed floors with a height of around 90-120mm, often with rough plywood panels. Then you place your floor surface on that.
If you're making a bathroom, for instance, you have 120mm to lay pipes, pour, and level with self-leveling compound.
Now, I'm not a builder or constructor, and I've seen maybe 2-3 floor constructions with aerated concrete. There are surely lots of ways to use those elements.
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The floor elements over the ground floor are 200mm thick, and yes, the floor on the upper floor is laid directly on the elements.
The initial post was a bit unclear; we want to both renovate the existing bathroom and furnish a new one. The considerations regarding cutting holes in the floor slab relate to the new one.
In the existing bathroom, we've determined that the penetrations for drainage were made between the elements, likely because this guarantees a wide reinforcement-free zone? The connections to the stack then hang in the ceiling of the floor below, with a "box" around them to conceal the pipes.
In the existing guest toilet, however, holes have been drilled in the middle of the elements, both for drainage to the toilet and the sink.
For the new bathroom, we hoped to avoid having pipes hanging from the ceiling on the ground floor, as they would then hang in the living room.
To summarize, I understand that:
- It should not be a problem to make a few small holes in the elements where needed
- We can't avoid horizontal pipes in the ceiling of the floor below because it's not okay to mill out channels in the elements
Do you agree?
The initial post was a bit unclear; we want to both renovate the existing bathroom and furnish a new one. The considerations regarding cutting holes in the floor slab relate to the new one.
In the existing bathroom, we've determined that the penetrations for drainage were made between the elements, likely because this guarantees a wide reinforcement-free zone? The connections to the stack then hang in the ceiling of the floor below, with a "box" around them to conceal the pipes.
In the existing guest toilet, however, holes have been drilled in the middle of the elements, both for drainage to the toilet and the sink.
For the new bathroom, we hoped to avoid having pipes hanging from the ceiling on the ground floor, as they would then hang in the living room.
To summarize, I understand that:
- It should not be a problem to make a few small holes in the elements where needed
- We can't avoid horizontal pipes in the ceiling of the floor below because it's not okay to mill out channels in the elements
Do you agree?