DIY Tank Grout Methods?

[BeardieFromTheNorth]

Kepler's mansion has been in progress for several weeks now - the back wall of the enclosure will all be filled with custom backgrounds. Since the tank is (assuming my math is correct) 160 gallons, there is plenty of area that needs to be covered with these backgrounds.

I've just sealed + stained the entire inside of the enclosure, and I'll be caulking all of the cracks tonight. My next step will be permanently installing the XPS boards that I've been building over the last week, then spraying foam in, and then grouting. My main concern right now is that the XPS board that I'm using is fairly shiny and smooth. I'm worried that the grout won't even stick to the boards that I've made, leaving bare spots or very thin areas. I'm curious if anyone knows of some methods to make the grout stick to the boards more effectively? My only idea thus far has been to use a low grit power sander to roughen up the surface of the boards, but I don't know if that will be enough. Any help or ideas are welcome!!!

P.S. It's still a work in progress, not everything in the pictures will make sense - just to give a glimpse of the vision: the ramp looking thing that Kepler is chilling on will form a boulder that encloses 1 gigantic hide that is separated in the middle to form 2 hides (there are horizontal blue lines on the right side that show where the 2nd level will be) - the lil guy has his own duplex in his mansion. The ledge will be sealed off, it's not a tunnel, and there's much more coming for the rest of the tank. Feel free to point out any oversights or dangers that you might find!!!! Thank you in advance!

 

[ChileanTaco]

I've just sealed + stained the entire inside of the enclosure, and I'll be caulking all of the cracks tonight. My next step will be permanently installing the XPS boards that I've been building over the last week, then spraying foam in, and then grouting. My main concern right now is that the XPS board that I'm using is fairly shiny and smooth. I'm worried that the grout won't even stick to the boards that I've made, leaving bare spots or very thin areas. I'm curious if anyone knows of some methods to make the grout stick to the boards more effectively? My only idea thus far has been to use a low grit power sander to roughen up the surface of the boards, but I don't know if that will be enough. Any help or ideas are welcome!!!

I have never used XPS boards. (Materials are a bit different here.)
But I can say: Everything sticks very well to styrofoam from packaging (used the styrofoam a fridge was packed in) and this is quite smooth, too!
What might help: Not putting the grout directly on the boards, but first the foam. I applied the construction foam everywhere, at least a thin layer.
A sander might also help (I don't own one so can't compare, but I didn't saw it necessary to use sanding paper).

Everything looks well-made in my opinion and the dragon can use it to his liking. I see no dangers here.

 

[BeardieFromTheNorth]

What might help: Not putting the grout directly on the boards, but first the foam. I applied the construction foam everywhere, at least a thin layer.

I hadn't thought about that. I'll have to test it out to see if the foam expands to a depth greater than the XPS board that I've been using to create the rocks on the walls. I guess I can always just carve out the excess material if there's too much.

Thanks for the tips!

 

[xp29]

Kepler's mansion has been in progress for several weeks now - the back wall of the enclosure will all be filled with custom backgrounds. Since the tank is (assuming my math is correct) 160 gallons, there is plenty of area that needs to be covered with these backgrounds.

I've just sealed + stained the entire inside of the enclosure, and I'll be caulking all of the cracks tonight. My next step will be permanently installing the XPS boards that I've been building over the last week, then spraying foam in, and then grouting. My main concern right now is that the XPS board that I'm using is fairly shiny and smooth. I'm worried that the grout won't even stick to the boards that I've made, leaving bare spots or very thin areas. I'm curious if anyone knows of some methods to make the grout stick to the boards more effectively? My only idea thus far has been to use a low grit power sander to roughen up the surface of the boards, but I don't know if that will be enough. Any help or ideas are welcome!!!

P.S. It's still a work in progress, not everything in the pictures will make sense - just to give a glimpse of the vision: the ramp looking thing that Kepler is chilling on will form a boulder that encloses 1 gigantic hide that is separated in the middle to form 2 hides (there are horizontal blue lines on the right side that show where the 2nd level will be) - the lil guy has his own duplex in his mansion. The ledge will be sealed off, it's not a tunnel, and there's much more coming for the rest of the tank. Feel free to point out any oversights or dangers that you might find!!!! Thank you in advance!

That's coming along pretty nicely
I can't wait to see the finished product
I'm afraid I'm not much help with the grout, the one time I tried using it ended with a huge mess and I don't even want to talk about trying to add the color in the grout

 

[ChileanTaco]

I guess I can always just carve out the excess material if there's too much.

That is what I did, especially if it looked too round and puffed up. I then just cut it straight.
Applying the grout was then quite easy. I had not much tools available (just moved internationally shortly before so not a situation like "I have this and that in my workshop") and just applied it with a cheap spatula and a plastic knife and everything went fine. Was even quite fun to make it

 

[BeardieFromTheNorth]

That's coming along pretty nicely
I can't wait to see the finished product
I'm afraid I'm not much help with the grout, the one time I tried using it ended with a huge mess and I don't even want to talk about trying to add the color in the grout

Thanks! I'm excited to see how it turns out too. I will definitely post pictures of the progress as I go. Still lots of work to be done!

I heard that the grout is the challenging part - I guess I'll see how it goes. I can always restart if I really have to.

 

[BeardieFromTheNorth]

That is what I did, especially if it looked too round and puffed up. I then just cut it straight.
Applying the grout was then quite easy. I had not much tools available (just moved internationally shortly before so not a situation like "I have this and that in my workshop") and just applied it with a cheap spatula and a plastic knife and everything went fine. Was even quite fun to make it

Well, I'll do my best and hopefully it comes out alright. I'm starting the spray foam tonight, so I'll find out how much of a catastrophe this will be!

 

[ChileanTaco]

I heard that the grout is the challenging part - I guess I'll see how it goes. I can always restart if I really have to.

The nice thing is, I think, really that with this method, quite natural looking shapes form, so normally even if it looks not exactly as planned, it will look natural and will be useful for your dragon. Especially with the foam and grout, this is not a "precise by the millimeter" thing but more like "I slap it on and it will look like some stone found somewhere in a desert"

Overall, I found the grout really not complicated, but it might differ regarding the exact type.
(For comparison, a few times I did something with concrete, like flower pots and other garden things - I once had one that was really nice to work with, a lot similar to clay, and then the second time one that was so bad we throw it away and called it for fun "Crumblerite".)

 

[Ninette007]

Kepler's mansion has been in progress for several weeks now - the back wall of the enclosure will all be filled with custom backgrounds. Since the tank is (assuming my math is correct) 160 gallons, there is plenty of area that needs to be covered with these backgrounds.

I've just sealed + stained the entire inside of the enclosure, and I'll be caulking all of the cracks tonight. My next step will be permanently installing the XPS boards that I've been building over the last week, then spraying foam in, and then grouting. My main concern right now is that the XPS board that I'm using is fairly shiny and smooth. I'm worried that the grout won't even stick to the boards that I've made, leaving bare spots or very thin areas. I'm curious if anyone knows of some methods to make the grout stick to the boards more effectively? My only idea thus far has been to use a low grit power sander to roughen up the surface of the boards, but I don't know if that will be enough. Any help or ideas are welcome!!!

P.S. It's still a work in progress, not everything in the pictures will make sense - just to give a glimpse of the vision: the ramp looking thing that Kepler is chilling on will form a boulder that encloses 1 gigantic hide that is separated in the middle to form 2 hides (there are horizontal blue lines on the right side that show where the 2nd level will be) - the lil guy has his own duplex in his mansion. The ledge will be sealed off, it's not a tunnel, and there's much more coming for the rest of the tank. Feel free to point out any oversights or dangers that you might find!!!! Thank you in advance!

Hey! I am in a similar position. I made the box out of white chipboard, and than mounted plasterboard over the inside. The xps will stick to it without a problem.

 

[MollyM]

Well, I'll do my best and hopefully it comes out alright. I'm starting the spray foam tonight, so I'll find out how much of a catastrophe this will be!

I agree with @ChileanTaco , I did the same and had no problem! Can’t wait to see your finished product !!

 

[BeardieFromTheNorth]

Thanks to everyone who replied on this thread! Apparently, I did a lot of work on Kepler's mansion over the last 10 days. Here are a few newer pictures of my progress!

For anyone in the future wondering about my original inquiry, grout does stick to XPS insulation board, but you will have to do several thin coats before you get the desired thickness. What worked for me was using a low grit sander to rough the boards up before grouting. A steel brush also worked and gave more of a texture, but demanded more work to get the grout in the cracks.

Anyways - I completed my first layer of grout this afternoon! It's still drying, but I'll put photos up when the grouting process is finished. But here are the pictures leading up to the grout after carving all of the expanding foam and installing the backgrounds. I think it's coming along pretty nicely, but let me know what you guys think!

 

[ChileanTaco]

Looks very nice!

And yes, it requires multiple layers.