At least in the US it is always better to get a fixed rate loan (meaning fixed for the life of the loan, typically 30 years).

This means your mortgage payment can never go up no matter how high rates climb in the market.

But if rates go down, you can always refinance to a lower rate and ratchet your payments down and lock them there.

It's as close to a free lunch as thing come. Your housing payment can never go up but can only go down.