We had 4.1m lean to shed spanning the width of a courtyard garden with sloping roof constructed against an 8' brick wall in September this year. The roof was covered in heavy duty roofing felt.
We agreed both verbally with the builder and in the working drawings supplied by us prior to construction that the shed roof should be chased in with lead flashing.
Unfortunately three months later water was pouring in the back wall and through a joint in the plywood roof. The builder was called back after recent heavy rain. He informed us that he didn't chase it in as there was no brick joint suitable. He had applied a cement fillet over the lead flashing which apparently broke down with -2 frost. He stated that he was not responsible for the weather. He also stated that at no point did he he say the lead flashing would be chased would be chased in.
To rectify this he suggested that the top layer of bricks be removed and lead flashing applied to the top of the wall and overlap down the sloping side of the roof. It was also covered a further 1m over the top of the wall which forms the external wall of a garage/parking area.
We are concerned that he has now laid it over the wall in 2.4 and 2.7 m lengths. British lead stipulate 1.5 maximum with fixing points and advised us that the lead will eventually crack or split due to thermal movement. He assures us that it is overlapping and not stuck down to allow for movement.
Can anyone advise us as to what we should do next? Can we seek professional advice? We are senior citizens and used Checkatrade to find a carpenter/builder in the first place. He has 40 year’s experience in carpentry and joinery and has worked as a building inspector. Any advice gratefully received. Apologies for long post.