Beginning in 1734, Ambrose landscaped the surrounding parkland and built to his own designs several Palladian follies, which still exist.

[4] Ambrose was an enthusiast for the Gothic Revival and planned to demolish the hall; commissioning Augustus Pugin (famous for his work on the Houses of Parliament) to design a replacement.

On their return, the ever-increasing cost of running and maintaining the building, their own failing finances and crippling inheritance taxes, and threats to the house's parkland from the urban sprawl of Loughborough and the construction of the M1 motorway which would cut directly through the park, all contributed to the decision to demolish Garendon.

[8][9] The new Garendon Hall planned by Ambrose Phillipps (1707–1737) was to be built in the Palladian style, eleven bays wide with a central portico topped with a triangular pediment.

The architectural historian Mark Girouard, in his study The Victorian Country House, reproduces an illustration of Pugin's plan, entitled "Merry England Revived".

[10] The attempt to mix Gothic and Palladian styles was stylistically unsuccessful, and Nikolaus Pevsner, in his 1960 Leicestershire and Rutland volume of the Buildings of England series, described the hall as looking “really rather horrible”.

[4] Elizabeth Williamson, in her 2003 revision of the same volume, was no more complimentary; "Pugin's huge mansard roof with Franco-Flemish dormers hideously upset the whole composition".

[12] Historic England suggest it is "perhaps the earliest example of an English building inspired directly from an Ancient Roman source.

[18] Remnants of the Palladian House also have Grade II listings and include the wrought-iron screens and gates,[19] a gateway and its associated railings,[20] and an entrance arch.

[21] The estate boundary wall is also listed Grade II,[22] as are various agricultural buildings including a barn,[23] outbuildings,[24] and a dovecote.