Repair or replace a commercial roof?
Three questions decide it: how much of the roof is damaged, whether the insulation underneath is wet, and how much life the membrane has left. A roof with a few problem details and dry insulation is a repair. A roof with widespread wet insulation, a failing deck or two layers already on it is a replacement. In between sits restoration with a coating.
Replacement, installed
$4 to $16 per sq ft
Tear-off adds $1 to $5 per sq ft.
Signs it is time to replace
- More than about a quarter of the roof needs work. Roofers commonly use 25 percent as the point where repairs stop making sense; it is a rule of thumb, not a code.
- Moisture surveys show wet insulation across large areas.
- The deck is rusting through, sagging or soft underfoot.
- The roof is at or past its expected life and leaks keep appearing in new places.
- There are already two roof coverings; the IBC does not allow a third to be laid over them.
- You need better insulation or a reflective roof for energy rules or tenants.
Repair, restore or replace: typical costs
| Job | Typical price |
|---|---|
| Repair Targeted fixes, per visit | $300 to $1,100 |
| Restore with acrylic coating Over a sound, dry roof | $0.65 to $1.75 per sq ft |
| Restore with silicone coating Over a sound, dry roof | $1.50 to $2.50 per sq ft |
| Replace with TPO Installed | $4 to $14 per sq ft |
| Replace with EPDM Installed | $4 to $13 per sq ft |
| Tear-off and disposal When the old roof must come off | $1 to $5 per sq ft |
Typical US prices from published national roofing cost guides, January 2026 editions, read November 2026. Installed, in US dollars, before any local tax. A guide, not a quote.
What the building code says about recovering
The International Building Code, Chapter 15 sets the rules most US jurisdictions adopt for reroofing. In short, a new roof covering cannot be laid over an existing one where the existing roof or roof covering is water-soaked or has deteriorated so that it is not an adequate base, or where there are already two or more applications of roof covering. In those cases the old roof comes off down to the deck.
Your city or county decides which edition applies and may add its own rules, so the permit office has the final word. Most jurisdictions require a permit for reroofing a commercial building.
What to ask for before deciding
A moisture survey
Cores or an infrared scan show how much insulation is wet. It is the single biggest factor in the decision.
The number of existing layers
A core through the roof shows whether a recover is even allowed.
A deck check
Rust, rot or deflection in the deck has to be fixed before any new roof goes on.
Repair and replace prices side by side
Ask the roofer to price both, so you can compare against the years each buys you.
Energy code needs
Replacing a roof usually triggers current insulation requirements under your local energy code; recovers and repairs often do not.
Warranty terms
What a new roof warranty covers (materials only, or labor and materials) and for how long.
Not sure whether to repair or replace? Have a commercial roofer who covers your area assess it.
Ask for a free quoteHow the decision usually gets made
Inspection and cores
A full walk, photos and core samples to see the layers and moisture.
Options priced
Repair, restoration and replacement, each with a price and expected life.
Cost per year
Divide each price by the years it buys. A cheap repair on a dying roof is often the dearest option.
Plan the work
Timing around tenants, weather and budget years, with permits where required.
Questions people ask
When should a commercial roof be replaced rather than repaired?
When damage is widespread (roofers often use 25 percent of the area as a guide), the insulation is wet across large areas, the deck is failing, or the roof is at the end of its life and leaking in new places each season.
Is it cheaper to recover a roof than replace it?
Usually, because there is no tear-off ($1 to $5 per sq ft saved). But the code allows it only over a dry, sound roof with fewer than two existing coverings.
Can a roof coating replace a new roof?
A coating can add years to a sound roof and is often far cheaper than replacement. It is not a fix for wet insulation, a failing deck or a roof that is already worn out.
How long does a commercial roof replacement take?
Small roofs can be done in days; large roofs over occupied buildings are worked in sections over weeks, with each section made watertight at the end of every day.
Does a new roof need a permit?
In most US jurisdictions, yes. Repairs below a set size are often exempt. Check with the building department.
Where our information comes from
Get a repair or replace assessment
The building ZIP, where to reach you, then a few taps about the roof. About a minute.
This is a free matching service, not a commercial roofer. We look for one who works in your area and tell you their name before anything is shared. Nobody contacts you until you say yes.
Thanks, your enquiry is in.
- We look for a commercial roofer who covers your building and does this kind of work, then email or call to tell you who it is.
- Your details reach that firm only if you say yes.
- They inspect the roof and give you a written price. No marketing from us, ever.