Glass blocks

[silver]

Hi guys,
I have tiled an ensuite shower cubicle where the back wall faces the front of the house / window
The customer has decided at the beginning to let light into the shower area by using glass blocks - Frosted to keep complaints down LOL !
I have tanked as normal and will be now additionally fittting the glass blocks. 16 to fit in a two column vertical.
I have checked the space to fill, laid all blocks out with the spacers and its all good with a couple of mill all round to play with.
I am going to use the correct mortar to "lay them" but intend to use a wide gap / waterproof / flexible grout to finish inside the shower and on the outside too.- gaps will be 10mm....grout is 2mm> 20mm....and grout as if tiling.
The shop said waterproof....but I expect it will be water resistant.

So...my question is...I intend if needed ? to add a further flex additive. The type as I have used in the past when using wide gap grout that comes as a two pack. (Tile world) just to give me an edge and prevent hairline cracks appearing.....any help guys ??
Thanks.

[MrE]

I've built quite a few glass block walls and used them for radius walls too on Cinema's etc and never had any hairline cracking. They are absolute evil (lots of swear words) to lay when walling, but what you are using them for is great. I've used a range of mortar for glass blocks, normally I use Colmef Vetromix or similar. I also rod and even place flat bed steel in the horizontal joints. All I would do if I was you, is lay them in those column, and use window L Shape lugs and screw them into the wall for every 2 blocks you lay so that they are tied to the building. As for the mortar, I've done both ie put a typical half round brickwork joint finish in the same day as construction, and also raked back 3-4mm and grouted as you do tiles with Colmef, its always seemed pretty waterproof to me. Golden rule with glass blocks, if you go out by 1mm, take that one off and relay, becasue you'll never get it back and always be fighting it. I used to lay a good 500 of these in my youth lol, now I hate laying 100, just had to do a wall for my sister. Some designer idea ie glass block wall to divide the living room from dining room with a mix of clear and coloured blocks. It was a success, everyone loves it and guess what they are nagging me to go do theirs - luckily I'm back to work and toooooooooo busy - have fun, at least you only got 16 :-)

[silver]

Thanks MrE....I appreciate your experience and advice...I hadnt reckoned on putting in the steel supports....because a) I havent done them before and b) thought only two columns with a good tight fit and mortar would be enough.......do I really need to go and get some ?

[MrE]

They are about 20p each and if it was me I would because it will give you lots of options as well as make them stong, after all its a stack bond pier in reality. The options they'll give you is this;

When laying they will stiffing up the column and you'll be able to do more, plus when they bite there will be less chance of movement ie as your laying. Sometimes you cant go more than 5 high in one hit, gets damn shakey but with the lugs in, have a brew, do something else for 30mins and you can plonk another 5 on or even 2, then 3 etc.

The other and very useful option they will give you is, say you got a 3 to even 10mm gap on one side then you can use that as a movement joint by leaving empty as you build and pump it full of mastic later and finish with good ole spit n finger.

The choice is yours, it will be fine without them as its wedged in a wall, but it may speed up installation and you could smack hell out of it later and it will not come out :-) The ones I use are L shaped, flat and thin with no fishtail on them. You can get plastic covers for them to allow for movement, when making movement joints, but you dont need to worry about that for this job. Sounds a great use of them and I bet it will make the room your doing look that more snazzy. Have fun :-)

[MrE]

Oh thought you'd like this, I built a large reception desk for a main car dealer a few years ago in like an S shape made out of coloured glass blocks to be lighted, in the ole days with normal mortar. When at a comfy height, the dealer owner said can the secretary pull her chair over to see if they are built to a suitable height for her. She pulls up her chair and sits mmmmmmm that nice, all the top dogs stood near looking saying "thats stuning" etc etc, so I said great all done, then in a blink of an eye the silly cow, pushed the fresh wall, like you push on a desk to make your chair go back to get up! KRRRRRRRRR SMASH, all my work on the deck - I was getting 1800 for the job, the manager and other top dogs fussed here and said it was an accident and that they'd pay me again to build it - well all I could do was try not to look gutted lol, with little work about it was double bubble, I could have kissed her, but it was still gutting seeing your work on the deck wrecked :-)

[Dave Ramsden]

Last time I did one I used BAL wide joint white grout. I know the people who I did the job from and if there was a complaint to be made any time after installtion they would definatley have said something.
To this day, nothing.

[silver]

Thanks guys...Cant wait to get at it now !!
Will get the brackets and save any probs if someone stands on the soap and falls into it !!!
Top advice fellas thanks

[Dave]

There has been quite a few threads on glass block installations......heres one link that some found useful..


Rods & Mortar Installation System | Glass Blocks | Install