From what I understand, after browsing some manufacturers/importers' websites, there are certain standard sizes for glass blocks that are used fairly consistently in both Europe, the USA, and China, such as 190x190x80 mm (LxWxD) or 240x240x80 mm, 145x145x95 mm, etc., to indicate the size of the blocks.
QUESTION: The specified dimensions when purchasing glass blocks I assume are those of the blocks themselves. But when later installing these blocks in, for instance, an exact opening in a solid concrete wall, do you need additional allowances for adhesive, sealant, or the like, or should you account for additional "installation space" to fit the blocks in place? If the opening in the concrete wall is (or is made) very precise in advance - to the millimeter - what margins should you consider for sealing in the glass blocks?
EXAMPLE: If I want to have a small section of glass block in an otherwise solid concrete wall, is it ENOUGH to make the opening in the solid concrete wall, for example, 600x150 mm in size, to fit four blocks in a row of 145x145 mm each? What is the MINIMUM extra space needed on the sides to glue/seal these blocks in the opening?
I am a millimeter counter and need to know exactly how it works. I have never installed glass blocks before.
QUESTION: The specified dimensions when purchasing glass blocks I assume are those of the blocks themselves. But when later installing these blocks in, for instance, an exact opening in a solid concrete wall, do you need additional allowances for adhesive, sealant, or the like, or should you account for additional "installation space" to fit the blocks in place? If the opening in the concrete wall is (or is made) very precise in advance - to the millimeter - what margins should you consider for sealing in the glass blocks?
EXAMPLE: If I want to have a small section of glass block in an otherwise solid concrete wall, is it ENOUGH to make the opening in the solid concrete wall, for example, 600x150 mm in size, to fit four blocks in a row of 145x145 mm each? What is the MINIMUM extra space needed on the sides to glue/seal these blocks in the opening?
I am a millimeter counter and need to know exactly how it works. I have never installed glass blocks before.
I assume that in your calculation example you intended for the grout to take 5 mm?
In that case, you've forgotten that for your 4 blocks in a row, there would actually be 5 grouts and 2 in height!
That is, the dimensions should be 605 x 155 if you want the same grout size everywhere.
In that case, you've forgotten that for your 4 blocks in a row, there would actually be 5 grouts and 2 in height!
That is, the dimensions should be 605 x 155 if you want the same grout size everywhere.
Yes, you are right - in this example, the numbers would be as you say, if all joints are 5 mm;
B-G-G-G-G-B (horizontally across the row of blocks)
B-G-B (vertically over each block)
5 and 2 joints respectively. B = concrete wall, G = glass block.
My main question, however, is, for example, is 5 mm enough (which would mean the opening in the wall must be 605x155), or what is the SMALLEST margin required to glue these glass blocks securely, professionally, and aesthetically pleasing? 0 mm, 3 mm, 5 mm, 12 mm, 35 mm...? And is the minimum joint margin the same both between different blocks and between blocks and the wall?
The question is asked in the context of the ongoing design of the concrete wall itself, in a prefab-concrete house (where I am installing these glass blocks myself afterward). I am currently instructing the wall manufacturer on how big a hole he should cast into the wall. This is done with lasers in the factory where they set the forms, so the opening in the wall is delivered with millimeter precision. It is just up to me to tell them how large the opening in the wall should be, where I later want to install my transparent blocks.
B-G-G-G-G-B (horizontally across the row of blocks)
B-G-B (vertically over each block)
5 and 2 joints respectively. B = concrete wall, G = glass block.
My main question, however, is, for example, is 5 mm enough (which would mean the opening in the wall must be 605x155), or what is the SMALLEST margin required to glue these glass blocks securely, professionally, and aesthetically pleasing? 0 mm, 3 mm, 5 mm, 12 mm, 35 mm...? And is the minimum joint margin the same both between different blocks and between blocks and the wall?
The question is asked in the context of the ongoing design of the concrete wall itself, in a prefab-concrete house (where I am installing these glass blocks myself afterward). I am currently instructing the wall manufacturer on how big a hole he should cast into the wall. This is done with lasers in the factory where they set the forms, so the opening in the wall is delivered with millimeter precision. It is just up to me to tell them how large the opening in the wall should be, where I later want to install my transparent blocks.
What you should do is go to the place where you plan to buy your blocks and actually buy them now. Then, lay them out at home as they should be assembled. That way, you can easily see any size deviations they have.
Finally, I would recommend that when it's time, you assemble them with elastic joints. Concrete and glass move slightly differently with, for example, temperature changes. I have seen many examples where glass blocks have been crushed due to this phenomenon.
Finally, I would recommend that when it's time, you assemble them with elastic joints. Concrete and glass move slightly differently with, for example, temperature changes. I have seen many examples where glass blocks have been crushed due to this phenomenon.
It is not potential dimensional deviations in the blocks themselves that I mean. (Such deviations from the factory are generally fairly small and these don't really concern me.)
It's the joints' width that I'm after, i.e., do the joints themselves create any additional space between the glass blocks that must be considered in calculations, and if so, how much?
Parallel: For example, when laying regular bricks, even if you line up all the bricks precisely next to each other before you start building, you miss the fact that mortar, about a centimeter or so, must be applied between each brick. It's easy to see on any brick wall. So even if you add up all the bricks in a row, a few centimeters still need to be added for the mortar, i.e., the joint material in the joints.
Now to the question again: When it comes to glass blocks, how wide are the joints typically considered during assembly/installation? Is it that all the joint material is within the small grooved area on the edges of these blocks, so that the "joint addition" in this equation is equal to zero, i.e., 0 mm additional in the row of blocks due to joints? Or is it like bricklaying, i.e., about 10 mm? Or another figure?
What is the narrowest joint width usually used for potential joint material between glass blocks, to make it stable and aesthetically pleasing?
It's the joints' width that I'm after, i.e., do the joints themselves create any additional space between the glass blocks that must be considered in calculations, and if so, how much?
Parallel: For example, when laying regular bricks, even if you line up all the bricks precisely next to each other before you start building, you miss the fact that mortar, about a centimeter or so, must be applied between each brick. It's easy to see on any brick wall. So even if you add up all the bricks in a row, a few centimeters still need to be added for the mortar, i.e., the joint material in the joints.
Now to the question again: When it comes to glass blocks, how wide are the joints typically considered during assembly/installation? Is it that all the joint material is within the small grooved area on the edges of these blocks, so that the "joint addition" in this equation is equal to zero, i.e., 0 mm additional in the row of blocks due to joints? Or is it like bricklaying, i.e., about 10 mm? Or another figure?
What is the narrowest joint width usually used for potential joint material between glass blocks, to make it stable and aesthetically pleasing?
There are different ways to mount glass blocks.
Gluing - you mount and glue a plastic spacer between all the blocks. Then you grout only for appearance's sake. However, I don't have measurements for the plastic spacer.
With glass block mortar - you use suitable spacers (similar to those used in tiles), which are available in sizes 2, 5, and 10mm as I have seen.
EDIT:
According to this guide, you place mortar at the bottom and polystyrene at the sides (5-10mm). It is suggested to use as much mortar at the bottom as you put polystyrene on the sides.
http://www.vetro.se/index.php?show=5571_SWE&&page_anchor=http://www.vetro.se/p5571/p5571_swe.php
Gluing - you mount and glue a plastic spacer between all the blocks. Then you grout only for appearance's sake. However, I don't have measurements for the plastic spacer.
With glass block mortar - you use suitable spacers (similar to those used in tiles), which are available in sizes 2, 5, and 10mm as I have seen.
EDIT:
According to this guide, you place mortar at the bottom and polystyrene at the sides (5-10mm). It is suggested to use as much mortar at the bottom as you put polystyrene on the sides.
http://www.vetro.se/index.php?show=5571_SWE&&page_anchor=http://www.vetro.se/p5571/p5571_swe.php
Last edited:
Bought glass blocks at K-rauta yesterday to build a partition wall with glass blocks on top for light entry. Asked the "expert". What I was wondering was how to fit the last piece in a sensible way. Now I can probably solve it since I'm building a new wall and can wait to put up side rails, etc. But if you cut out a hole in an existing wall, it's not possible to work magic. I think it will be necessary to mortar the last one. Anyway, the expert in the store called their "expert," who in turn called their...
And I don't think they came up with anything I hadn't already thought of.
Good luck
And I don't think they came up with anything I hadn't already thought of.
Good luck