Hi we have noticed new cracks in our property. When we purchased the house 3 years ago there were a few cracks and we were told the house had been underpinned 30 years ago when a side extension was put on.  We knew that there was always a risk. The people before had definately done some poor DIY on the property but maybe stupidly we decided to purchase. Anyway we have noticed a few more cracks recently and measured a pre existing hairline crack which has lengthened by about an inch. Part of the work done on the house was replacement of windows and doors and there has definately been brickwork moved i presume for different sizes. Above the kitchen door now the lintel is shorter than the frame and there definately seems to be bowing in the frame with the bricks about also showing cracking in between. Could the ahort lintel be to blame for some of this cracking? Ive added a photo in my gallery