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How Much Does a Commercial TPO Roof Cost?

TPO is the most common roof on flat commercial buildings, and its price depends heavily on what's underneath it. Here's what goes into the cost, typical 2026 price ranges, and how to compare bids for a building in St. Charles County.

Typical TPO Price Ranges in 2026

Every building is different, but published 2026 cost guides give a useful starting point. These are national averages; local prices vary with labor, material costs, and the building itself.

  • TPO membrane and installation, by thickness: roughly $3.00 to $4.50 per square foot for 45-mil, $4.00 to $6.50 for 60-mil, and $5.50 to $8.50 for 80-mil.
  • Tear-off of the existing roof: commonly adds about $1 to $2 per square foot for removal and disposal.
  • Complete tear-off projects with new insulation to modern energy code: commonly in the range of about $9 to $14 per square foot all-in.

Recovers, where TPO goes over an existing roof that's still dry, tend to land toward the lower end because there's little removal and less new insulation.

The honest answer: The only way to get a real number is to look at the roof. The same 20,000 square foot warehouse can be a straightforward recover or a full tear-off with wet insulation and deck repairs, and those are very different prices.

What Drives the Cost

Tear-off or recover

Removing the old roof adds labor, disposal and time. If the building has only one roof and it's mostly dry, a recover avoids most of that. If there are already two roofs, or the insulation is wet, tear-off is required.

Insulation

Missouri follows energy codes that require meaningful roof insulation on full replacements. Insulation is often one of the largest line items, and tapered insulation to fix ponding adds more.

Membrane thickness

60-mil TPO is the most common choice for commercial buildings. 45-mil is cheaper but thinner; 80-mil costs more and adds durability.

Roof details

Every rooftop unit, pipe, drain, skylight and wall needs custom flashing. A roof with lots of equipment and penetrations costs more per square foot than an open warehouse roof.

Size and access

Larger roofs usually cost less per square foot because crews and equipment work more efficiently. Small roofs, tall buildings, and tight sites cost more.

Deck repairs

Rusted metal decking or rotted wood found during tear-off has to be replaced. Good bids explain how deck repairs will be priced.

How to Compare TPO Bids

  • Is it a tear-off or a recover, and how many existing roofs are there?
  • What insulation type and thickness is included? Is there a cover board?
  • What membrane thickness?
  • Is new edge metal and coping included?
  • How are rooftop units, curbs and drains detailed?
  • How are unexpected deck repairs priced?
  • What warranty is offered, and from whom: contractor, manufacturer, or both?

Could You Spend Less?

If your roof isn't wet throughout, you may not need a new roof at all. Repairs or a restoration coating can often add years for a fraction of the cost. See our guide to coating vs. replacement, or ask for a free assessment and we'll tell you which makes sense.

Common Questions

What is the average cost of a TPO roof per square foot?

Published 2026 national cost guides commonly put the TPO membrane and installation alone at roughly $3 to $8.50 per square foot depending on thickness, and complete tear-off projects with new insulation at roughly $9 to $14 per square foot. Your building's size, condition and details decide where it lands.

Is 60-mil TPO worth it over 45-mil?

For most commercial buildings, 60-mil is the common choice. It's thicker, handles foot traffic and weathering better, and costs moderately more. Thicker 80-mil membranes are used where extra durability is worth the higher price.

Why do commercial roofing bids vary so much?

Bids often differ in what they include: insulation thickness, cover board, tear-off versus recover, flashing details, edge metal, and warranty. Make sure each bid covers the same scope before comparing prices.

Is a coating cheaper than a new TPO roof?

Usually much cheaper, often a fraction of replacement cost, but only if the existing roof is a good candidate. If the insulation is wet throughout, a coating isn't a good investment.

Want an exact price for your roof?

Serving commercial buildings in St. Charles, St. Peters, O'Fallon, Lake St. Louis, Weldon Spring, Dardenne Prairie, Wentzville, Defiance, Foristell and New Melle.

Call (636) 206-7785