It's the society wedding of the year, so Pippa Middleton is loosening the purse strings for her wedding to her hedge fund manager fiancé James Matthews this Saturday (20 May).

The 33-year-old nearly-royal may not experience life in a palace like her sister, the Duchess of Cambridge, but that doesn't means She has to miss out on her wedding day.

Middleton – who will reportedly wear a custom made gown by Giles Deacon for her big day – is creating a regal setting for her nuptials with a glass palace.

The author and her super-rich groom – 41-year-old Matthews – have splashed out on the conservatory which she is having installed in her family's home in Bucklebury, Berkshire.

The huge glass building is reportedly being shipped in from Belgium and will presumably be used for the reception following the ceremony at St Mark's Church near the Middleton residence.

It is being installed by Peppers Marquees – which has a royal link by holding the only warrant for supplying marquees to the Prince of Wales.

Pippa Middleton
Pippa Middleton is set to say 'I do' as she weds James Matthews on May 20 Reuters

Over the past week, Middleton has been spotted around South Kensington and in and out of skin clinic Santi London.

Pippa Middleton and James Matthews
Pippa Middleton and James Matthews leave after attending the morning Christmas Day service at St Mark's Church in Englefield on 25 December 2016 Andrew Matthews

Today, (16 May), several women were seen arriving at her £17m mansion, which she shares with Matthews, with one carrying what looked like a bridal gown.

Sources have also claimed that workmen have been busy since the weekend putting up the glass palace on a camouflaged stage in a field at the rear of Michael and Carole Middleton's home.

It is expected to take six days to finish building and is so large that it can be seen from both the main road and public footpath running alongside the estate.

More than 300 guests are set to attend the reception – including Prince Harry's girlfriend Meghan Markle – despite only 150 people going along to the day ceremony on a ''no ring, no bring'' policy. This means that guests can only bring plus ones if they are married or engaged.

According to Kensington Palace, Prince George, three, will be a page boy at the wedding, while Princess Charlotte, two, will be bridesmaid.