Change allowed size of patios and decks

I was refused allowance of an enlarged patio in my backyard. The Architecture Board Rules call for patios or decks to be no more than 20% of the rear yard. I would like to see this increased to at least 35%. I cannot fit a table, yard swing and barbecue pit on my 20 % patio right now. I had intentions to remove the existing grass, add perennials and reduce the maintenance of the backyard, but this was rejected. The bylaws need to be changed.