Capital gains exemption limited where additional residential property is owned, purchased or constructed, affecting rollover relief eligibility. The proviso to section 54F is substituted to disapply the capital gains exemption where the assessee owns more than one residential house other than the new asset, or purchases such a house within one year of transfer, or constructs such a house within three years of transfer, and where income from the additional residential house is chargeable under the head 'Income from house property.'