44.— (1) Subject to subsection (2), a building owner may carry out works to a party structure for the purpose of—

(a) compliance with any statutory provision or any notice or order under such a provision, or

(b) carrying out development which is exempted development or development for which planning permission has been obtained or compliance with any condition attached to such permission, or

(c) preservation of the party structure or of any building or unbuilt-on land of which it forms a part, or

(d) carrying out any other works which—

(i) will not cause substantial damage or inconvenience to the adjoining owner, or

(ii) if they may or will cause such damage or inconvenience, it is nevertheless reasonable to carry them out.

(2) Subject to subsection (3), in exercising any right under subsection (1) the building owner shall—

(a) make good all damage caused to the adjoining owner as a consequence of the works, or reimburse the adjoining owner the reasonable costs and expenses of such making good, and

(b) pay to the adjoining owner—

(i) the reasonable costs of obtaining professional advice with regard to the likely consequences of the works, and

(ii) reasonable compensation for any inconvenience caused by the works.

(3) The building owner may—

(a) claim from the adjoining owner as a contribution to, or deduct from any reimbursement of, the cost and expenses of making good such damage under subsection (2)(a), or

(b) deduct from compensation under subsection (2)(b)(ii),

such sum as will take into account the proportionate use or enjoyment of the party structure which the adjoining owner makes or, it is reasonable to assume, is likely to make.

(4) If—

(a) a building owner fails within a reasonable time to—

(i) make good damage under subsection (2)(a), the adjoining owner may apply to the court for an order requiring the damage to be made good and on such application the court may make such order as it thinks fit, or

(ii) reimburse costs and expenses under subsection (2)(a) or to pay reasonable costs or compensation under subsection (2)(b), the adjoining owner may recover such costs, expenses or compensation as a simple contract debt in a court of competent jurisdiction.

(b) an adjoining owner fails to meet a claim to a contribution under subsection (3)(a), the building owner may recover such contribution as a simple contract debt in a court of competent jurisdiction.