Two routes, not one
People often search for this as a retrospective warrant, but that is not the name in the Act. The Building (Scotland) Act 2003 gives two routes.
A late application, while the work is under way. Section 15 lets you apply for a warrant late, at any time before a completion certificate has been accepted. The section 15 text is headed late applications.
A late completion certificate, once the work is finished. If the work is complete, section 17 lets the person responsible, usually the owner, submit a completion certificate without a warrant ever having been granted. The Scottish Government’s procedural handbook covers it.
The work is judged by today’s rules
The work has to meet the building regulations in force at the time of the late submission, not the rules in force when it was built. The council can ask for parts of the work to be opened up so it can inspect them. There is no time limit on a late completion certificate, but the longer the gap, the less likely it is that work will comply.
What it costs
City of Edinburgh Council and West Lothian Council both charge more for the late routes. A late warrant is 200% of the normal fee, and a completion certificate with no warrant is 300%. See the cost page for the bands and a worked example. These are on top of any design work and any corrective building work.
West Lothian Council also offers a paid letter of comfort, which it limits to work completed before 1 May 2005, expired warrants and exempt work. It says the letter is not a replacement for a warrant. Work finished before 1 May 2005 follows a different route, and the City of Edinburgh Council publishes separate fees for it.
What the law says about starting without one
Carrying out work that needs a warrant without one is an offence under section 8 of the Act. The people it can apply to are the person doing the work, the person it is done for, and the owner. The Act includes limited defences in some circumstances. They do not cover everyone named above, so take advice rather than assuming one applies.
A council can also serve a building warrant enforcement notice under section 27. It can require a warrant, a completion certificate or changes to bring the work into line. The notice must allow at least 28 days after it takes effect, and an appeal goes to the sheriff within 21 days under section 47. Failing to comply is itself an offence, and the council can do the work itself and recover the cost.
Selling a property
City of Edinburgh Council says that having no warrant may affect your ability to sell. If you are buying or selling a home with significant work done, your solicitor is the right first call.