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· Västerbottens län
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What would a glidskikt be?
Your question is a bit short, but I suspect it arises because some surveyor has commented on this, but I could naturally be wrong...
But if we take the question literally, there have been slip layers in masonry constructions since ancient times, i.e., far more than a hundred years back, perhaps even several hundred years.
The primary purpose of the slip layer is to reduce the stresses that arise around all openings in a masonry wall when the house moves, and especially stresses in the arches above doors and windows, where you often see crack formations if built without a slip layer.
Skilled master masons knew that this should be included in the first or one of the first layers, and mainly used tar paper. There were, however, no building standards from the beginning, and this was knowledge that has been studied in more detail in recent times. There are quite a few investigations on this, for instance, from LTH in Lund from the 80-90s, where stress measurements were done in masonry constructions and different slip layers were also compared with masonry without slip layers. Normally, one can say that a slip layer of paper combined with a weaker mortar gives better results than with, for example, stainless steel since the friction is less.
The secondary effect of the slip layer was also to prevent capillary rising moisture from being transported up into the masonry.
Now to what I suspect regarding your question.
What today is called a slip layer is a combination of a slip layer and a device for water transport out of the masonry if, for example, wind-driven rain has entered the backside of the outer wall. This type of slip layer/water drainage sheet is combined with open butt joints and is a fairly modern invention from the 80s and later.
If we look at different masonry veneers, it was common long ago to build full-thickness walls, i.e., brick through and through, but later started to build with an air gap, i.e., a masonry veneer. Originally, it was a way to insulate, and it was built without insulation boards but with completely sealed joints and bricked crown, i.e., a completely "airtight" wall. But the wall was often standing on a slip layer. But note that there was no building code mandating the slip layer, just good craftsmanship. There are plenty of walls without slip layers!
What happened in the 60s-70s was that more consideration was given to energy saving, and thus started placing a board between the shells, often a mineral wool board, but still often without all the open butt joints seen on houses today. However, cladding or masonry veneers were most common on houses with different forms of "stone structure," i.e., a masonry inner shell and not as now with wood/plasterboard wall inside the brick facade.
What happened was that in the late 70s and early 80s, thoughts began about the problems of penetrating moisture, and therefore started using open butt joints to get water out of the wall and then began to fold up the paper placed under the outer wall but folded up against the inner to allow any water to drain out. Meanwhile, many began questioning whether the open butt joints were good considering the air movement it created inside the wall.
Several research projects were initiated in the mid-80s regarding this as there was no building code established for how open butt joints together with a suitable slip layer should be designed.
So a simple answer to your question, if it’s about the issue of not having a slip layer that at the same time should conduct out any penetrating water, there were no standards for this in the 60s. There was probably also no clear written standard that it must have a slip layer, but it was up to the builder to ensure to avoid problems with cracks around, among other things, the vaults in the façade.
So my view is that your house may very well have been constructed according to the standards of the 60s without a slip layer, and especially without the modern stainless-steel plates used today.
But if we take the question literally, there have been slip layers in masonry constructions since ancient times, i.e., far more than a hundred years back, perhaps even several hundred years.
The primary purpose of the slip layer is to reduce the stresses that arise around all openings in a masonry wall when the house moves, and especially stresses in the arches above doors and windows, where you often see crack formations if built without a slip layer.
Skilled master masons knew that this should be included in the first or one of the first layers, and mainly used tar paper. There were, however, no building standards from the beginning, and this was knowledge that has been studied in more detail in recent times. There are quite a few investigations on this, for instance, from LTH in Lund from the 80-90s, where stress measurements were done in masonry constructions and different slip layers were also compared with masonry without slip layers. Normally, one can say that a slip layer of paper combined with a weaker mortar gives better results than with, for example, stainless steel since the friction is less.
The secondary effect of the slip layer was also to prevent capillary rising moisture from being transported up into the masonry.
Now to what I suspect regarding your question.
What today is called a slip layer is a combination of a slip layer and a device for water transport out of the masonry if, for example, wind-driven rain has entered the backside of the outer wall. This type of slip layer/water drainage sheet is combined with open butt joints and is a fairly modern invention from the 80s and later.
If we look at different masonry veneers, it was common long ago to build full-thickness walls, i.e., brick through and through, but later started to build with an air gap, i.e., a masonry veneer. Originally, it was a way to insulate, and it was built without insulation boards but with completely sealed joints and bricked crown, i.e., a completely "airtight" wall. But the wall was often standing on a slip layer. But note that there was no building code mandating the slip layer, just good craftsmanship. There are plenty of walls without slip layers!
What happened in the 60s-70s was that more consideration was given to energy saving, and thus started placing a board between the shells, often a mineral wool board, but still often without all the open butt joints seen on houses today. However, cladding or masonry veneers were most common on houses with different forms of "stone structure," i.e., a masonry inner shell and not as now with wood/plasterboard wall inside the brick facade.
What happened was that in the late 70s and early 80s, thoughts began about the problems of penetrating moisture, and therefore started using open butt joints to get water out of the wall and then began to fold up the paper placed under the outer wall but folded up against the inner to allow any water to drain out. Meanwhile, many began questioning whether the open butt joints were good considering the air movement it created inside the wall.
Several research projects were initiated in the mid-80s regarding this as there was no building code established for how open butt joints together with a suitable slip layer should be designed.
So a simple answer to your question, if it’s about the issue of not having a slip layer that at the same time should conduct out any penetrating water, there were no standards for this in the 60s. There was probably also no clear written standard that it must have a slip layer, but it was up to the builder to ensure to avoid problems with cracks around, among other things, the vaults in the façade.
So my view is that your house may very well have been constructed according to the standards of the 60s without a slip layer, and especially without the modern stainless-steel plates used today.
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"Your question is a bit brief, but I suspect it's because a surveyor has commented on this, though I may be wrong..."
Thank you for your reply, Oceanis, that's correct a surveyor pointed it out.
He also noted that the brick façade is attached with long nails that have rusted (no moisture or mold is present) and that the nails were in too few places. My question is, was there anything else to use in the 1960s, and were there regulations for it? The technical description from the construction exists, and the municipality has granted building permits. What was right then might be wrong now and vice versa, how do I address this?
Thank you for your reply, Oceanis, that's correct a surveyor pointed it out.
He also noted that the brick façade is attached with long nails that have rusted (no moisture or mold is present) and that the nails were in too few places. My question is, was there anything else to use in the 1960s, and were there regulations for it? The technical description from the construction exists, and the municipality has granted building permits. What was right then might be wrong now and vice versa, how do I address this?
The brick façade is attached with long nails that have rusted (there is no moisture or mold) and there were too few places where nails were used.
Also a common problem in houses with brick façades from the 1960s. Galvanized nails were used back then, with about 5 - 6 nails per square meter. Similarly, above windows, where ordinary rebar was used, it rusts and first pushes out the joint, but also causes the bricks to loosen and fall.
Even if your façade is incorrectly constructed, it's impossible to come now after 50 years and try to make someone else than yourself pay for any measures.
Also a common problem in houses with brick façades from the 1960s. Galvanized nails were used back then, with about 5 - 6 nails per square meter. Similarly, above windows, where ordinary rebar was used, it rusts and first pushes out the joint, but also causes the bricks to loosen and fall.
Even if your façade is incorrectly constructed, it's impossible to come now after 50 years and try to make someone else than yourself pay for any measures.
The concrete answer is that the clasping could very well be of the "nail" type, as there still exists what is known as "murkamspik."
The problem is that well into the 70s materials used in clasping were not stainless steel. In the Swedish Building Code from '67, it states for example that "the connection should be made with corrosion-resistant material if there is a risk of corrosion," which left it somewhat up to the builder to assess the risk of corrosion and which material should be used. Often these clasps were galvanized but untreated ones also occurred. Even the galvanized ones are today in many cases rusted out as they may have been exposed to moisture for more than 50 years.
The number of clasps could also be quite few if it was a wall that wasn't very high. There are cases where they only have 2-3 clasps per m2. If it's not specifically stated in the drawing how many should be used, it was a bit up to the bricklayer to assess, but I wouldn't be surprised if there are only 2-3 clasps in your wall as it was probably not uncommon at that time.
I do not know the reason for the questions, but clasps being rusted away is a common problem and must be considered normal maintenance for a wall from the 60s, and it is usually not a major problem to fix.
The problem is that well into the 70s materials used in clasping were not stainless steel. In the Swedish Building Code from '67, it states for example that "the connection should be made with corrosion-resistant material if there is a risk of corrosion," which left it somewhat up to the builder to assess the risk of corrosion and which material should be used. Often these clasps were galvanized but untreated ones also occurred. Even the galvanized ones are today in many cases rusted out as they may have been exposed to moisture for more than 50 years.
The number of clasps could also be quite few if it was a wall that wasn't very high. There are cases where they only have 2-3 clasps per m2. If it's not specifically stated in the drawing how many should be used, it was a bit up to the bricklayer to assess, but I wouldn't be surprised if there are only 2-3 clasps in your wall as it was probably not uncommon at that time.
I do not know the reason for the questions, but clasps being rusted away is a common problem and must be considered normal maintenance for a wall from the 60s, and it is usually not a major problem to fix.
"Even if your facade is poorly constructed, it's impossible to come now after 50 years and try to get someone other than yourself to pay for any measures."
thomas the facade doesn't have to be poorly constructed just because it wasn't built in 1960 the way it is now, right?
What I'm wondering is if you can say a facade is poorly constructed for that reason?
thomas the facade doesn't have to be poorly constructed just because it wasn't built in 1960 the way it is now, right?
What I'm wondering is if you can say a facade is poorly constructed for that reason?
"A layer of tar paper or sheet metal placed under one of the first courses of bricks in a masonry wall to, among other things, reduce stresses around openings in the wall."
The facade/house is built according to the Hultsfredshus model, I don't see any tar paper between any bricks but between the bricks and foundation wall, is it the same thing?
The facade/house is built according to the Hultsfredshus model, I don't see any tar paper between any bricks but between the bricks and foundation wall, is it the same thing?
The same thing. It is most common that it is located between the foundation wall and the first course, so that is completely correct.pikapika said:
One usually has to scrape a bit in the joints to see the felt, and sometimes the plaster has been extended on the foundation so that it lies over and up on the first brick, so it can be difficult to see. But I'm a bit curious about the competence of the inspector if he/she missed it. Maybe too young and only experienced in new constructions
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If the facade is built according to the accepted method at the time it was constructed, you can hardly say it is poorly constructed. You can't apply 2016 regulations to a house built before these regulations even existed.pikapika said:
If you read my previous post (post no. 3), I wrote exactly that. The risk of cracking is the primary reason to have a slip layer in a masonry construction. Whether cracks will occur completely depends on the movements that occur in the building after it is completed. In your case, living in Skåne, one can assume you have a house built on clay, which poses a significant risk for movement in the house and also for cracking. But if the house is from the 60s, you can just look and see if there are any significant cracks; if they haven't appeared after 50 years, it's unlikely they will appear now or in the future due to any potential lack of a slip layer. Look especially around windows and doors, and especially around the arches above; hairline cracks may be present and do not necessarily indicate a problem.pikapika said:
In my opinion, the fact that the foundation's plaster is pulled up and over the paper is a construction error.oceanis said:You often have to scrape a little in the joints to see the paper, and sometimes the plaster has been pulled up on the foundation so that it lies over and up on the first brick, making it difficult to see. But I do wonder a bit about the competence of the inspector if he/she missed that. Maybe too young and only experienced in new construction
The raised paper acts as a collection for any water/moisture that penetrates the back of the brick. This then follows the paper.
If the paper is covered with plaster (usually quite hard), the moisture is prevented from escaping and instead goes down into the foundation wall. If there is a basement below, you can get moisture problems for that reason.
When you talk about raised paper, you're thinking of a modern construction from the late '80s or later. It was around then that they started using open butt joints and a layer of paper that was bent up against the inner wall. In older constructions, they didn't have this concept, and they didn't even have open butt joints for ventilation or water drainage. Back then, the sliding layer was solely a sliding layer, and there are many foundation walls that go up half a meter above the ground with a sliding layer between the wall and the brick wall, but which then have a plaster that lies 4-5 cm outside of the foundation and which ends precisely at the edge of the lower course. This is how many old houses look, and these are not construction errors; it's how they were built in the past. Go out and look at brick houses from the first half of the last century, and you'll find lots of these houses, especially in southern Sweden below Småland. I don't think you'll find any where you can see any paper sticking out.roland53 said:
So, construction error, I don't know if I can agree with that.
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