Building
noun
A thing you build is a building. There aren't too many other things you build, at least not to this extent.
たてもの
The reading is a bit weird. It's kun'yomi readings across the board, meaning your knowledge of 建てる hopefully can come into play here. A building is something you build, so how do you say "to build"? It's 建てる (たてる). Since it's a thing you build, it's a たてもの. This reading is a bit confusing, but hopefully after a while you'll get it if you get it wrong too many times! Maybe if you think about the building you're in and call it a 建物 a few times it'll sink in better?
すてきなデザインの建物ですね。
This is very nicely designed building, isn't it?
建てられてからまだ一年しかたってないのに、あの建物はもうずい分よごれているね。
It's only been a year since it was built, but this building is pretty dirty already, isn't it?
「あなたとその建物を一緒に見に行きたいと思うのですが、いつがご都合よろしいですか？」「ええっと、あなたのご都合に合わせますよ。」
"I’d like to go see the building with you so when would be convenient for you?" "Well, I’ll adjust my schedule accordingly."