if they are to stay outside year round, then you will need loads of hay to stuff the hutch with, a few snugglesafe heatpads, thermal and waterproof hutch covers. Ideally moving the hutch into a shed or garage. If that isn’t possible, then positioning the hutch in the most sheltered part of your garden. Also have a thermometer on the hutch so you can monitor the temperatures.
My two live in my shed. They have a 6ft hutch in the shed.
I keep mine warm by stuffing the hutch completely full with hay. They also have four snugglesafe heatpads within the hutch. I put two under two hides and then the other two pads elsewhere in the hutch. That way they can choose whether to be in a hide with or without a heatpad.
The hutch itself then has a thermal hutch cover, then two blankets, then the waterproof hutch cover (it’s obviously not needed to keep them dry given it is in a shed but it offers another layer to keep warmth within), then an old duvet thrown over all of it. They do have a two storey hutch but the ramp is removed and only use the top half of the hutch for mid winter night times. They have the downstairs part of the hutch and the shed floor as their main living space for most of the year and then use it as play space during the winter. They get shut in the top half of the hutch at night during the coldest parts of the winter as it is easier to keep just one level warm enough.
These measures have worked very well, the shed itself staying 5-10 degrees warmer than outside temperatures so within the hutch is at least 12 degrees. I did have to bring them indoors last winter though. I knew it was going to get down to -8 outside so brought them indoors. When checking the hutch the next morning, it and was down to just 2 degrees in the hutch so I’m glad they were indoors!
