I will try to summarise. We have moved in to a property with a rear and side extension that have built over the access to drains. The side extension was done in the 90s when I don't think the water authority owned drains on private land. We have managed to pull up laminate flooring in our utility room and get access to that drain.
The rear extension done in 2016 built over another drain access point, but this is concreted over and definitely not accessible. There is a "rodding point" at the back of the house though.
We have had a drain company come to do a survey and they said drain access was OK as long as we keep the drain accessible from the utility room. The condition of drains is also OK, but they are coming back to cut away roots that have grown in to the drains.
My question is whether we should contact Seven Trent Water and try and get a retrospective build over agreement from them. A previous set of buyers to us pulled out of buying this property because of the issue with drains and I am just thinking of if we ever come to sell I don't want this issue to cause problems. But I don't know how complicated it would be to get this sorted. Anyone have experience?