Roof terrace issues - help!

JBPhysio

I own my ground floor flat ( leaseholder) and I also own 50% of freehold with owner flat upstairs. 
He has a roof terrace over my back bedroom ( it was established late 1980 when the building was converted into 2 flats) and it is demised on his lease, so there is no dispute as to who owns it. However. In 2015 it leaked very badly and he had it repaired ( it was covered in roof felt, but not reinforced to make it a structurally sound roof for human traffic/use). I am about to do a side return extension for my flat and the sider return extension will adjoin the roof terrace. So of course, his roof terrace will now be over my new kitchen/diner. We don;t know the exact structure until we pull my ceiling down, but who is responsible for making sure the roof terrace ( which is essentially the same as a floor in the rest of his flat) is sound proofed, insulated/thermoregualted) etc to prevent damp/moisture/sound. He is extremely possessive over the roof terrace ( does not want it touched, affected,changed etc - mostly because if it is rebuilt he will need to get planning permission for it (Wandsworth council). As it is demised there is not a lot I can do about the fact it exists but I want to make sure that there are no issues with it when I do my build especially if I want to sell the property in the future. 
Thanks for your help. 

anselld

Presumably your extension would need permission from "the Freeholder", ie both of you jointly.  Which would imply that you need to reach an agreement with upstairs.  The starting point for negotiation would presumably be your extension so your responsibility to ensure the roof is built to whatever standard is required.

Will he be extending the roof terrace over the new extension?  

diggingdude

If he extends his terrace he should be contributing to the cost 

eddddy

It's potentially a complex situation...

But in simple terms, you probably have to negotiate with your neighbour to reach an agreement. If you really can't reach an agreement, you'd have to go to tribunal/court to let them decide what is 'reasonable'.

You will probably need to get the leases (and lease plan) updated to reflect the new maintenance responsibilities, to avoid problems when you sell.

For example...

• Does the lease say you are each responsible for 50% of the maintenance and repair costs of the original building?
• If so, who is responsible for maintenance and repair of the new extension and newly created roof terrace?
• As your flat will be bigger with the extension, is 50% each still fair? Or should it become 55% / 45%?

There may be quite a few issues with the lease that need to be addressed, to avoid problems in the future.

greatcrested

How are repairs to the structure of the building apportioned in the leases? Just because the existing terrace is 'his' does not mean he is soley responsible for repairs. Cost may be shared. I can't see your leases!

Same would be true of any new extension/terrace.

Since you cannot extend without his consent as joint freeholder, you will need to negotiate and agree with him on

* your extension,

* his new terrace and access,

* construction costs and standards of construction (eg if he is to have terrace access, the extension roof must be suitable as a terrace, not just as a roo

* your respective maintenance liablilties

* shared costs of amending both leases

* etc

I suggest a solicitor experienced in leasehold matters as well as your surveyor/architect.

theoretica

As a starting point I would suggest building the extension with a sloping roof not suitable for access.  If he wants something accessible he will have an incentive to pay/take responsibility.

greatcrested

theoretica said:

As a starting point I would suggest building the extension with a sloping roof not suitable for access.  If he wants something accessible he will have an incentive to pay/take responsibility.

That's fine, provided he agrees. As joint freeholder, he could simply refuse to agree the extension.....

JBPhysio

Thank you for all your comments. 
As I am leaseholder ( and joint freeholder) I need a license to alter which we are in process of negotiating, using a surveyor and in which we are resolving these issues. I as leaseholder have to submit all my plans etc to the freeholders ( me and him), for approval - freeholder can;t be unreasonably obstructive ( in theory....). He won;t be extending his terrace and my planning permission states that the roof I am building in the side return which will have skylights in cannot be used for anything other than a roof. His roof terrace already exists but my concern is that is is not structurally sound as in built for walking on. 
The lease states that we have an informal agreement to split 50% of external repairs - for example, outside painting, main roof, gutters, but when a roof area is demised to a lessee then I thought it is treated as an outdoor room so you become responsible for the roof as you would internally be responsible for your floor above another lessee. 
It's a very valid point about in my interest to make sure the roof is soundproof watertight and safe so that will be written in the license to alter and tbh if it costs me a bit more to do that it's to my benefit esp if i sell at some point. . If anyone can recommend a solicitor experienced in this kind of thing re : leases and share of freehold I would appreciate it. Thank you

JBPhysio

Noted - that i need to add who is responsible for maintenance of my new roof. There won;t be access to my roof from his flat or roof terrace as it is enclosed by railings and will stay enclosed
He has a loft extension  so his flat is already much bigger than mine. 

greatcrested

JBPhysio said:

...
As I am leaseholder ( and joint freeholder) I need a license to alter which we are in process of negotiating, using a surveyor and in which we are resolving these issues. I as leaseholder have to submit all my plans etc to the freeholders ( me and him), for approval - freeholder can;t be unreasonably obstructive ( in theory....).

I'm not an expert here but would have thought that extending the extant of the demised area of your lease would require suitable compensation to be paid to the freeholder. The value of your lease is increasing and the freeholder will be entitled to benefit from this surely?

He won;t be extending his terrace and my planning permission states that the roof I am building in the side return which will have skylights in cannot be used for anything other than a roof. His roof terrace already exists but my concern is that is is not structurally sound as in built for walking on.

So the existing roof issue is entirely separate from the extension issue.

The lease states that we have an informal agreement to split 50% of external repairs

This seems very unusual - indeed unlikely. However, please quote the relevant wording in full.

- for example, outside painting, main roof, gutters, but when a roof area is demised to a lessee then I thought it is treated as an outdoor room so you become responsible for the roof as you would internally be responsible for your floor above another lessee. 

Impossible to be sure without seeing the precise wording in the lease, however I would anticipate that the existing roof (his terrace floor) would be 50% shared cost.

Search for local solicitor with relevant area of expertise here.