Is this a "new" way to use the word Demise?

I have worked in the construction industry in the UK and in Australia and have increasingly heard the term "demise" being used to mean "within the boundary of" in both countries. For example:

We are seeking construction drawings for the structure within the demise of the room/building/project/site

OR

those services do not belong to the demise of the room/building/project/site

Definitions I've found of demise don't really fit this usage, which seems to be more closely related to the word "demesne".

While I try not to be a prescriptivist, I do find it slightly jarring because I've never associated this word with this meaning. Any thoughts on the origin of this usage?

Solution 1:

Demise in this context is commercial real estate legal jargon for a lease or an area that is leased. Like lease, it appears that demise is also used as a verb and a participle adjective.

Here’s some wording from The fundamentals of commercial leasing:

The first issue to be determined in any lease is what is being demised. The demise is the area of the building or facility designated for the exclusive use of the tenant... Licensed areas may also be included in the lease alongside the demised areas... While “demising” the whole or part of a property gives the tenant exclusive possession, landlords usually reserve the right to enter the premises for various purposes...
_{Source: The Free Library — The fundamentals of commercial leasing.}

The British National Corpus returns results for the demise from Drafting business leases by Kim Lewison (1985-1994). (Click to expand examples and see items 43 to 66. Also see BNC results for demised.)

Here are a few excerpts showing usage:

45: If the draftsman wishes to create a lease for a period that can not be made certain at the time of the demise the only way is to express it as being granted for a fixed term subject to a power to break at the expiry of the period.

50: It is, however, established that the demise of one floor of a building extends at least as far as the underside of the joists supporting the floor above it... The ordinary expectation is that the tenant will be entitled to occupy all that space between the floor of his demise and the underside of the floor above... So the demise of a flat or a particular floor of a building will include a roof space accessible only from that flat where there is no reservation to the landlord... However, a demise of a “suite of rooms” on the top floor of a building will not include the common roof...

54: Where the demise includes the whole of a building (or the top floor) the draftsman may therefore wish to consider whether the airspace above the building should be excluded from the demise.

61: The draftsman should therefore consider whether the landlord should have the right to enter the demise for other purposes...

I’m not so sure your examples are being used in the way that you think they are — that is, to mean “within the boundary of” and unrelated to property leasing; I can easily imagine these to fall in line with the definitions of lease or an area that is leased:

We are seeking construction drawings for the structure within the demise of the site. —> We are seeking construction drawings for the structure within the leased area of the site.

Those services do not belong to the demise of the building. —> Those utilities are not included in the lease [or leased area] of the building.

Solution 2:

OED has:

1. a. Law. Conveyance or transfer of an estate by will or lease.

   1509–10 Act 1 Hen. VIII c. 18 §2 All Dymyses, Leses, releses..made..by her or to her.

2. Transference or devolution of sovereignty, as by the death or deposition of the sovereign; usually in demise of the crown.

3. Transferred to the death or decease which occasions the demise of an estate, etc.; hence, popularly, = Decease, death.

While the found use of demise seems to be closer to "demesne" than sense 1 here, it's possible that sense 1 has been extended to the demised property itself in a somewhat similar way to the word now meaning "death" via sense 3.

The OED entry was last updated in 2019 and doesn't seem to have caught up with this jargon: it may be a very recent coinage.