My neighbours tall conifers are overgrown and are now coming in way of my building work

I think you would be within the right to cut them right back on your side.

There is little that you can do. You can cut any overgrowth on your side of the boundary but you must inform your neighbour before commencing work. There is a process of getting a local council to review if the trees are an evergreen hedge and if they are a nuisance. This costs about £300-400 and is something you would have to pay upfront and is non refundable. They will assess the impact of a hedge above 2 metres, so anything above 2 metres might be termed a nuisance or it may not. Basically you can do little as your neighbours garden is theirs and not yours.

Conifers are an awful nuisance. They are a fire hazard, especially in this hot weather, as they are dry as tinder in the middle. If there is a bit of glass in there ............

I know because some boys set fire to 3 Council ones at the end of my garden, set my garden on fire. It was an awful shock. The Fire Brigade were a bit slow coming, and a good neighbour came round with a hose pipe, but the pressure from a kitchen tap wasnt strong enough to penetrate inside to the top of each tree. The Firemen brought another hose from their lorry, which sent the water up 50 feet. I had asked for these trees to be cut down as they were not my property. So the Council got the Bill for the Fire Brigade, and the cost of Tree removal.

The shock of it made me ill. Your neighbour may not know this happens, and be worried about the £400 cost for each tree. I think you need help.
I would advise to go to your Citizens Advice Bureau. There may some other way of dealing with these trees,
and your neighbour. Do you have an Estate Manager ?

The problem is people want a cheap evergreen screen from their neighbours. Conifers are not the most elegant solution and get out of hand quickly and cause a lot of neighbour disputes and as Diane has just said are a potential fire hazard something I never thought of! You have to balance neighbours privacy and letting a screen get to silly proportions. An offer of a trim and prune is probably the way to go - so bite the bullet and speak to the neighbour pleasantly and tell them the problem and offer a solution. I know it is difficult if you do not know your neighbour but reassure them that the screen will not be affected and at little cost to them.

The fire danger will still be there. Go to Citizens Advice Bureau - worry about this can make you ill.

It is quite possible to reduce the height of tall conifers without harming them. Your neighbour might be more amenable to this than to removing them altogether.