These entries cover the preparations for work beginning. As the house was being almost completely pulled down (the last entry for August 1st probably refers to walls at basement level, all that remained of the old house) and rebuilt there was a lot to do. Soane's diary reveals that on 29th June he was 'at home all day about 4th Lecture and plan of Mr. Tyndale's House'. He was also 'Ab: plans of Mr. Tyndale....' on the 30th and 'at home all day about plans of next House' on the 2nd & 3rd July. Eliza Soane left for Chertsey as work began and on 4th July she sent Soane a note ‘I thought on you all day – for this day you begin your house’: this does not seem to have been a joint project! On the 5th July Soane was 'At Mr. Tyndale's & Mr. Pullen about party wall' - an agreement would not be reached until the beginning of August.
After the house was vacated the next stage was to auction the materials making up the existing house on the site, which Soane intended to demolish. By this date Soane’s plans for the re-building must have been fairly well advanced and he was talking to contractors: his diary records a meeting with his stonemason: Settled stonework of new House with Mr. Grundy.
The auction was conducted by Messrs. Creaton & Son, on the premises, and a copy of the catalogue survives in the Soane Archive (XVI.J.9). The materials are advertised as those of a substantial brick dwelling house, with stone string and cornice and all lots purchased are to be immediately taken down and cleared away by the purchasers. The Conditions of Sale state that this must be at the buyers expense and within the following stated times: The Tiling and other covering, skylights, sashes and frames, and internal Fittings, 4 days; and the boarded and timber floors 7 days; respectively from the Day of sale.....The several purchasers are to be answerable for all Damage..... in taking away their Lots from the Premises they are to be compelled to cut off the Ends of all Timbers laying into Party or External Walls on which their Lots may happen to abutt... All Lots that remain uncleared.. shall be resold....No persons suffered to pull down before Six o'clock in the Morning, nor after Six in the Evening'. In effect, those who bid at the auction were responsible for the demolition of the existing house on the site. The list of materials to be disposed of covers everything except the furniture and reveals many fascinating details about the previous house on the site, which dated back to 1753 and had five gables. The 'Amount of sale' came to £454.18.3, which, less commission meant a profit for Soane of £420.15.9. It appears from the auctioneers account that only one lot, 111, the last one in the sale, which was The whole of the plates, bond timber &c. in the walls, may have been unsold.
The start of demolition is also recorded in Soane’s diary for 17th July: 'Began pulling down Mr. Tyn:s late house' [e.g. former house]. Throughout the rest of July & August Soane's diary records that he continued to be busy preparing plans for the new house. Friendly relations continued throughout with Mr. Tyndale, with whom Soane visited Dulwich and dined on July 29th. On the day that demolition began Mrs. Soane retreated to Chertsey, returning for only a few short visits to London until the end of September when she went to Brighton for a week. Her Notebook for August 9th, a Sunday, records Mr. Soane fetched me from Chertsey after staying there 3 weeks & 5 days. Archive bills show that while the demolition was taking place Soane’s carpenters, Richard Martyr and Son, were busy on site, for example on 25 July Shoring up the End of the House & making good Weatherboarding &c. and on 8 August making moulds for Bricklayers & masons &c. They were also preparing timbers by treating them with tar oil. As well as the work carried out in July & August by Richard Martyr, Soane's favoured Smith, Thomas Russell, supplied various metalwork including Round rods and Ironwork for Truss Girders as well as Bolts, Nutts & plates 13 I[nches] long'.