Yes, any will involving a house has to go to probate.
The will directs the executors what to do with the estate. Probate is the procedure whereby the law gives effect to the various property transactions required to enable the executors to carry out the transactions required to give effect to he will. In other words a will isn't a title deed. Probate enables the executors to grant a title. If there was no will then there would be no executors and no ability to say what was to happen to the property.