Blocking of front balcony

Q: Sir,

I had booked a flat No. 1012 (area 1060 sq.ft) in “Impression 58” apartment located at Raj Nagar Extension, NH-58. The 95% of the payment have also been made (with around 80% loan from HDFC Bank). As per the lay out plan shown to me and builder buyer agreement, apart from the other accommodations, the flat has three balconies (one each with bedrooms and drawing room).
2. I opted for this specific flat and incurred the additional expenses in the form of PLC @ 50/- sq. ft. amounting to Rs. 53000/-, because of the spacious front open balcony leading to well ventilated front bedroom and keeping in view the resale/rental value in future.
3. On 10.4.2011, when I went to see the progress of my flat I was shocked to see that 90% of my front balcony (attached with the front bedroom) has been covered with the front elevation (without my knowledge and consent). As a result my balcony has been transformed into a box, spoiling the entire ventilation of the flat. Not