Unless you’re going to remove them every spring, you will also need devices that can survive the summer in an attic, and that typically means heat of 140°F. So keep that in mind as well.
CaoGadgets Kumo Wireless Tags Should be able to handle it. You can get integration either through their IFTTT channel or there’s community – created code. These are really well engineered devices, but they won’t integrate directly. You’ll need their $40 bridge and each sensor is about $30.
The other thing that’s good about these is they have fantastic range, much better than zigbee or zwave Which can be helpful because it can be tough to get signal out of an attic due to installation, water pipes, and other issues.
The Aeotec and Fibaro multisensors can handle the cold, but may not be able to handle the heat. So again, depends whether you’re willing to remove them every spring