Hi thanks for your question. My name's XXXXX XXXXX I'm going to assist you with it this evening.
If he made the agreement either in his home or via a "distance contract" (e.g. over the phone, by mail order, television etc.) than he is entitled to a statutory 7 day cooling off period. However, an agreement to start the work within this period can be deemed a waiver of his cooling off rights.
Under both the Distance Selling Regulations (DSR) and the Cancellation of Contracts made in a Consumer's Home or Place of Work etc. Regulations (CCHR), in order to be an effective waiver, the cooling off period rights must be clearly set out in writing and, in respect of the latter, the consumer must have signed his agreement for the work to start within the statutory cooling off period.
If he was not advised of his rights and (in respect of an agreement made in his home) he did not expressly agree in writing that the work should start before the statutory cooling off period then the agreement is unenforceable. If he was appropriately advised, what are his rights?
Well, he should still be perfectly able to cancel without financial consquences if the work has not yet started. Under the DSR if you agree for the work to start before the end of the cooling off period, you still have the right to cancel up until the the point at which the service starts. If the contract was made in his home, under regulation 9(2) of the CCHR, the contractor can only claim for "goods or services that were supplied before the cancellation". If the contract hasn't commenced yet, this would presumably be nothing. Things would be different if any of the goods were bespoke (but I very much doubt this would be the case with an alarm system).
You must serve the notice of cancellation in writing and send it to the party referred to in the cancellation notice. Email is fine and any letter is deemed to be sent on the date of posting.
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