Tear-off, recover, and what decides it
Commercial Roof Replacement in Dallas, TX
Nobody can price this from the parking lot. What is already stacked on your deck, and how much of it is holding water, sets the entire scope.
Everything above the roof starts with the deck. Concrete, steel and wood each change how a new assembly gets attached.
The core cutter answers the first question
A core comes out as a stack. Reading it top to bottom tells us how many roofs are already up there, what insulation is under each one, how thick that insulation is, whether it is holding water, and what the deck is made of. That stack is the whole basis of the scope, and no amount of walking the roof substitutes for it.
Deck type changes the work more than anything else. Steel decks rust from the top down where a leak has been running, and rusted flutes have to be cut out and replaced before anything goes over them. Concrete decks hold moisture and often need a vapor retarder considered. Wood plank moves and needs plates sized for it. Gypsum and cementitious wood fiber decks turn up under older commercial buildings, and neither takes an ordinary roofing screw, so attachment moves to anchors made for that deck with pullout values proven on site before the assembly is specified.
We pull cores in more than one place. A single core in a dry corner of a hundred thousand square foot roof describes that corner. Cores in each quadrant, plus cores in every area that has leaked, describe the roof.
Tear-off or recover
A recover leaves the existing roof in place and installs a new assembly over it. It is faster, it produces almost no landfill volume, and it is the right call on a specific and fairly narrow set of roofs: one existing roof covering, dry insulation, a substrate flat enough to build on, and a structure with room for the added weight.
It gets ruled out for concrete reasons. Building codes generally stop you at two roof coverings, so a roof already carrying a recover has to come off. Wet insulation is disqualifying no matter how small the percentage sounds, because moisture sealed under a new membrane keeps degrading the board and corroding the deck out of sight. A badly uneven surface, deteriorated deck, or an attachment that cannot be verified all point the same direction.
When cores show moisture in a meaningful share of the field, the arithmetic stops being close. A recover priced honestly against that roof already carries the cost of cutting out and replacing the wet board, and it still leaves a deck nobody has inspected sitting under two roof coverings.
Deck repair, drainage, and insulation
Once the old roof is off, the deck gets inspected in daylight with nothing on it. Corroded flutes, deflected panels, failed welds at the bearing, and holes from removed equipment all get addressed then. That is the only moment in the roof life when the deck is visible, and skipping it means building a new roof on a known defect.
Drainage gets corrected before any membrane goes down. If the roof ponded before, it will pond after, unless something changes the slope. Tapered insulation, crickets built between drains and behind curbs, sump receivers set at the drains, and additional drains or overflow scuppers where the field cannot get water anywhere are the tools. Standing water two days after rain shortens the life of every membrane made, and most manufacturer terms exclude water that sits past the drainage window they specify.
Insulation is where the energy code lands. Current requirements for a low-slope replacement in this climate zone are well above what most existing buildings have, and getting there usually means two layers of board with staggered joints rather than one thick layer. Staggering matters: a single-layer install leaves a continuous thermal path at every board joint across the entire roof.
Sequencing around a building that stays open
The schedule is built backward from your operation. Dock doors that run at six in the morning, tenant hours, kitchen exhaust that cannot shut down, a data room that cannot be exposed, and rooftop units serving occupied space all set constraints before the first square foot is scheduled.
We open only what the crew can close that day. Each section is sized against the forecast and the crew count, and the roof is watertight before anyone comes off it, every night, including nights when the radar looks clear. Interior protection goes under any area being worked over sensitive space.
Perimeters and corners get enhanced attachment. Wind uplift is not uniform across a roof: the corners see the highest pressures, the perimeter zone next, and the field the least. Fastener density steps up accordingly. Roofs that peel in a North Texas spring storm almost always start at a corner where the pattern was run at field spacing.
What you hold at closeout
A drawn record of the finished roof. It names each layer in the order it was installed, gives the board thickness and the fastening density used in the field, the perimeter and the corners, and locates the drains, overflow scuppers, curbs, pipes and hatches on a scaled plan. Tie-in details are drawn where the roof meets a wall, an expansion joint or an adjacent level. Someone opening that roof five years from now starts from a drawing rather than from exploratory cuts.
The paperwork issued for the assembly that went on your building, turned over complete instead of reduced to a cover sheet. Read the conditions attached to it, because they are the part that governs: inspection at a stated frequency by a qualified party, drainage kept open, damage repaired promptly and by approved methods, and notice filed within a set number of days when something fails. Alterations by another trade, including a rooftop unit set without proper flashing, are typically excluded.
A written inspection calendar keyed to those conditions rather than to a generic annual reminder. In this climate that generally means two scheduled visits per year placed on either side of the storm and heat seasons, with extra visits added after severe weather. The calendar arrives with the deficiency reporting format we use going forward, so findings are recorded the same way from the first visit on and the file stays comparable year to year.
Steel deck
Rust starts under old leaks and works down the flute. Corroded panels get cut out and replaced while the deck is open and visible.
Concrete deck
Holds construction and infiltrated moisture. Attachment shifts toward adhesive or specialized anchors, and a vapor retarder gets evaluated.
Gypsum and plank decks
Common on older Dallas stock and unreliable for fastener pullout. Adhered assemblies usually make more sense than mechanical attachment.
Tapered insulation
Crickets between drains and behind curbs, sump receivers at the drains, and enough fall that the field is dry two days after rain.
Attachment and uplift
Field, perimeter and corner zones each get their own fastener density. The corners are where a failure starts.
Phasing and dry-in
Sections sized to the weather window and the crew, with the roof closed watertight before the crew leaves the site each day.
Common questions
How many roofs can be stacked on one building?
Building codes generally allow two roof coverings before a full tear-off is required, and there are exceptions that force removal sooner, including saturated insulation and a deteriorated deck. A core tells us how many are already there. If your roof is carrying two, the next one is a tear-off regardless of the condition of the top layer.
How much wet insulation makes a recover a bad idea?
Any confirmed saturation in the area to be recovered is a problem, and most specifications treat a small single-digit percentage of the field as the practical ceiling once wet areas are cut out and replaced. Beyond that you are replacing so much board that the labor savings of a recover disappear and you are gambling on the parts you did not core.
Can you replace the roof while we keep operating?
That is the normal case. Work is sectioned so no area sits open, deliveries and hoisting are staged around dock and tenant traffic, and dust and odor sensitive areas are identified before the schedule is set. Rooftop units serving occupied space are coordinated so nothing critical goes down during business hours without you knowing in advance.
Do we have to add insulation to meet current code?
A full replacement generally triggers current energy code for the roof assembly, and current requirements are meaningfully higher than what most existing buildings in this area have. That usually means additional board thickness, which in turn affects flashing heights, curb heights, door thresholds, and edge metal. Those adjustments belong in the scope from the start, not as change orders.
How long does a commercial roof replacement take?
Crew size, square footage, deck repairs, and weather set the duration, and in North Texas spring the weather is the variable that moves most. A useful way to think about it is that the schedule is built in daily watertight increments, so a rain day costs a day rather than reopening finished work.