structural changes to a leasehold

hi,

I've read other posts and you mention

s.19(2) of LTA 1927:

"In all leases whether made before or after the commencement of this Act containing a covenant condition or agreement against the making of improvements without a licence or consent, such covenant condition or agreement shall be deemed, notwithstanding any express provision to the contrary, to be subject to a proviso that such licence or consent is not to be unreasonably withheld."

in my lease all it says is "not to alter the leasehold property externally or cut or maim any structural part thereof or erect any further building or addition upon the leasehold property or make any external projection from the property or carry out any act which constitutes material development...." it doesn't mention any allowance with permission.

does this also fall within the act, that I can do structural improvements with permission that should not be reasonably withheld, or does the act only come in force when the lease states that improvements are allowed with permission?

also, the changes I would like to make are structural but internal ones. do you think that It could be argued that the wording of the lease refers to external structural changes only as internal issues are not dealt with in this paragraph, they are dealt with on the next one and there seems to be no further prohibition on making changes?

many thanks,

steve