· by Michael Blair, Nashville's Contractor
Renovation budgets are exceeded so consistently that a contingency is part of the budget rather than an admission of poor planning. In Nashville’s older housing stock, discoveries are the expectation.
How much to hold
Ten to fifteen percent on newer construction, and fifteen to twenty on anything built before roughly 1970 where the systems are original or unknown.
Hold it separately rather than mentally, or it gets spent on upgrades before the surprises appear.
What triggers it here
Knob and tube or aluminum wiring found in a wall. Galvanized supply piping. Drain lines that do not meet current code once altered. Rot at a wall base or under a bathroom.
Then: a wall that turns out to be structural, and asbestos or lead in a house of the right vintage.
- Ten to fifteen percent on newer homes
- Fifteen to twenty percent pre-1970
- Old wiring found once walls are open
- Galvanized or failed supply piping
- Rot at wall bases and under bathrooms
- A non-structural wall that turns out to be structural
Reduce the unknowns first
Exploratory opening before finalizing the budget is cheap relative to what it reveals. Opening a small area of wall and looking in the crawl space answers several questions for very little.
A contract that names per-unit prices for likely discoveries — per sheet of sheathing, per foot of pipe — converts a surprise into an arithmetic problem.
Spending it deliberately
Contingency is for discoveries, not upgrades. Spending it in week two on better tile means the rot found in week five has no budget behind it.
If the project finishes without needing it, that is the good outcome rather than a wasted allocation.