I’m buying a new build property and the builder has insisted I exchange within 28 days. Is this possible?

In principle yes. This is a tight time frame but if the builder provides a full pack of papers on day one and the searches which have to be carried out arrive back in time, this is a workable timescale. Most builders allow a degree of flexibility if the transaction is well progressed and there are perhaps just a few outstanding matters to be dealt with.  Exchange will normally take place with a completion date “On notice”.  This means the builder once exchange will provide us with ten days notice to get your transaction to complete.