Borg

George Borg appeals from an adverse judgment in his action against respondent Transamerica Insurance Company for breach of a duty to defend under the terms of a comprehensive general liability policy. The action arises out of Transamerica’s denial of Borg’s tender of the defense of a third party lawsuit, alleging damages on account of a structural encroachment from real property belonging to Borg over adjoining real property belonging to the third party. Borg contends the trial court erred in determining that Transamerica had no duty to defend the lawsuit because the encroachment was created prior to the effective date of Transamerica’s insurance policy. We agree with Borg, and therefore reverse the judgment.

Factual and Procedural Background

Borg purchased residential real property in Redwood City in 1971. Included in the purchase were three structures that encroached from the property onto an adjoining vacant lot: a redwood deck extending six to eight feet out from the house, overhanging a hillside and resting on concrete piers; three wooden planter boxes terraced down the hillside; and a concrete pad for a garage. In 1986, Borg performed work on both the deck and the…