I have 20 7-ft high photinias with a disease planted close to my house, which may be the cause of my foundation problems. Do I need to dig up the roots? The bark is very hard.
Certified GKH Gardening Expert
From what I understand, these shrubs have a fairly heavy, or extensive, root system so it is possible that they could be interfering with your foundation but only if they were planted within 5 ft. or less of your home. If they are diseased, it is likely from a fungus, which is common in these shrubs. While treatment is possible, I would recommend transplanting them elsewhere if your foundation is being affected by the roots.
I would first try treating the fungus issue so they are somewhat healthy prior to moving. You might also need to prune them back by about a third. These articles will help: https://www.gardeningknowhow.com/ornamental/shrubs/photinia/photinia-leaf-spot.htm