So, here's the plan for Waffles' enclosure. Above our stairs to the upper floor of the house, there's a platform. That's where we're going to build Wafles' home. It will be a sort of L shape, since the hallway is attached to the platform. I'm not sure how to explain the dimensions. It'll be about 35 square feet, give or take a few inches. But, since we have the verticle space, it will be 2 layers, each at least 3 feet high.
The lower level will be his cool, humid area. It will have a digable substrate, a hide, and a small water dish. And, of course, a ramp to the upper level. The upper level is a little more interesting. This will be hot, but still relatively humid. There will be another hide, a basking rock (or something equivalent), and his very own in-ground pool.
We're going to get a koi pond connecter and set it into the floor/ceiling. Obviously in a way we can still get it out! We're thinking of stick on "tiles" for the upper substrate. All together it will be around 70 square feet.
The framework will be wood, and the outer sides will be plexiglass. We're also going to figure out a way to mount the lights on the top of the enclosure. Luckily it will be near the only outlet in the hall. I'd especially appreciate some advice for the building process! I need to know what I should make it out of, what I should seal it with, things like that.

With the in-ground pool I would use something that you can remove.
It will take a lot of work to keep it clean as monitors are messy animals.
Being able to remove it for a good cleaning will make your life a lot easier.
Go with 3/4 inch plywood sealed with either polycrylic (many coats) or a safe epoxy such was Epoxy by the Leading Epoxy Manufacture | WEST SYSTEM Epoxy (single coat)

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Mike

The easiest way to keep the pool clean is with a filter system...too much work involved in constantly changing the water otherwise....My exterior "Fluval" filter works perfectly well, I change the carbon etc. around once per month...very easy!

You can also put a pvc drain in it, that would allow you to change the water when you need to without removing the pool. You would just have to make sure you had access to the drain. If you go with the Min Wax polycrylic(satin finish) a 1 gallon can will cover 300 sq ft and you would only need 3-4 coats (I used 3 coats on my Chinese Water Dragon's enclosure and it's working great)

Thanks so much for the help! I'll likely use a filter for the "pool". What I have in mind for the pool seems like it would be easy to romove and clean daily, but then again I've never had to carry it full of water, lol, just saw it at the store

Consider the drain aspect as well that Steve suggested. It would allow a quick water change if you had issues with the filtering system.

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Mike

Just keep in mind that water weighs 8.35 pounds per gallon.
In quantity it gets really heavy, really fast!

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Merlin,
What's Life Without A Little Magic!

My present filter has been working for over 6 years, 24/7, not one single problem..... ( Fingers crossed, now I`ve said that!) When you get the pool, I`ll be happy to advise how I`ve fitted the aquarium heater, and the pipes for the filter, just let me know....

Thanks all! It'll be a few months before we start building, but I still want to be prepared early

can you really get filters good enough to get the poo out? I would have thought it would get clogged up? how much does the filter cost and how much to replace the carbon every month?