i would never ever,put my house on the line ,but i have a relatively small mortgage and a good percentage of equity in my house as i built it myself.it would probably only add £100 quid a month on the repayments and to me a 500 is as good as money in the bank . as saphbe said people do it to put a new kitchen or build a sunroom on to their house and whats the ressle value of a second hand kitchen or sunroom maybe ten percent after years i reckon.im not rushing out to do it [sorry paul,i do love it though] as the economy isnt stable enoug at the minute.
cheers james