UK citizens 3 months in New Zealand then flying to UK via Beijing (5 night stopover)

My husband and I will be spending January to March (3 months) in New Zealand. We will be flying back to the UK via Beijing, and have booked our flights to allow a 5 night stopover. We have independently booked a hotel in Beijing. Please can you advise if we need a visa, what sort or visa we would require, and when and where we could arrange this? Our flights with Air New Zealand have been booked to land in Beijing 29th March, and depart to London on 3rd April. Thank you.