Perimeter seal and door bottoms
Weatherseal, Threshold and Sweep Replacement in Charlotte, NC
If you can see daylight around a closed door, describe where.
Call the crew (984) 398-5248The least costly failing component in the building, and the one nobody reports
Nobody submits a work order because a door sweep is worn. The door still opens, still closes, still locks. So it stays worn for years while conditioned air leaves through a gap the width of a pencil across the bottom of an entrance that gets used eight hundred times a day.
Charlotte makes this worse than it looks on paper. Long humid summers mean an exterior door with a failed perimeter is pulling moist air into a conditioned lobby all day, and the visible consequences turn up somewhere else entirely — condensation at the ceiling diffuser near the entrance, a carpet edge that stays damp, an entry mat that never quite dries. Those get reported as HVAC problems and investigated as HVAC problems.
The four places an exterior opening leaks
Seal is a perimeter, and a perimeter is only as good as its worst section. Replacing three sides of it is a common and expensive way to achieve nothing measurable.
Head and jamb weatherstripping
Adhesive-backed, kerf-mounted or applied stop gasketing depending on what the frame accepts. The failure is almost always hardening rather than tearing — a compression seal that has gone rigid stops sealing long before it looks damaged, which is why visual inspection under-reports this by a wide margin.
Door bottoms and sweeps
Surface-mounted sweeps, mortised door bottoms and automatic drop seals. High-cycle entrances destroy these on a predictable schedule, and a sweep dragging on a threshold also adds opening force, which is where this turns into an ADA question on interior openings.
Thresholds and saddles
Worn, loose, or corroded thresholds, and the sealant bed underneath that has usually failed first. A threshold that has come loose at the fasteners is a trip hazard before it is an air leak, which changes its priority considerably.
Meeting stiles and astragals on pairs
Pairs leak in the middle and nearly everybody replaces the perimeter without touching it. Overlapping astragals, meeting stile gasketing and, on rated pairs, the coordinator that has to let them close in the right order.
What drives a weatherseal figure
| Variable | Why it matters | How it is settled |
|---|---|---|
| Whether the frame takes a kerf profile | A kerfed frame accepts a proper compression seal. A frame without one needs applied gasketing, which is a different product and a different life expectancy. | Confirmed on survey. Two minutes to check, and it changes the whole specification. |
| Threshold condition and what is under it | Replacing the seal above a failed threshold is temporary. Lifting a threshold can find a sealant bed, a corroded substrate or a slab that has moved. | Inspected before quoting, because this is where surprises live. |
| Rated or smoke-rated assembly | Labelled openings need listed gasketing and, where smoke is in scope, an intumescent or smoke seal rather than a weather seal. The two are not interchangeable and are frequently substituted for each other. | Label located and recorded first. |
| Pairs versus single leaves | A pair has a meeting stile, usually an astragal and often a coordinator, none of which exist on a single door. | Counted on survey. Pairs are routinely mis-counted as two singles. |
| Opening cycles | Product selection follows traffic. A heavy-duty sweep on a low-use door is money spent, and a light one on a main entrance is a repeat visit. | Estimated from use, and corrected at the next visit if it turns out wrong. |
Product cost on this work is minor. Access, threshold condition and whether the assembly is labelled account for nearly all the variation.
How the work runs
Walk the exterior openings
Interior lights off where the building allows it. Daylight gets photographed and located per opening rather than described generally.
Check the frame profile
Kerf or no kerf, stop condition, and what the existing gasketing was. Determines the product before anything is ordered.
Locate labels
Any labelled opening moves to listed products. This gets settled before quoting, not after delivery.
Lift the threshold
On any opening where the threshold is in scope, or where there is evidence of water. What is underneath decides whether this is a seal job or a repair.
Specify per opening
Buildings rarely need one product across the site. Main entrances, service doors and stair discharge doors take different profiles.
Fit and set
Perimeter first, door bottom second, threshold bedded in sealant where applicable. Fasteners into substrate rather than into old holes.
Re-check closing and latching
New seal changes both. Closer valves and latch engagement get verified before we leave, because a properly sealed door that no longer latches is a worse outcome than the leak.
Why this work is handled the way it is
The whole perimeter or none of it
Replacing the sweep and leaving hardened jamb seal produces an opening that measures almost exactly as leaky as it did before. If only part of the perimeter is in budget, we will say which part is actually leaking rather than which part is easiest.
Seal type follows the assembly, not the catalogue
Smoke seal, weather seal and sound seal look similar in a supplier listing and do different jobs. On a labelled opening the wrong one is a finding at the next inspection.
Thresholds get lifted, not looked at
The substrate under a threshold is where water damage hides. Quoting one without lifting it is guessing at the part of the job most likely to grow.
Opening force gets re-checked afterwards
New perimeter gasketing adds resistance. On interior openings that can push a door past the ADA 2010 Standards section 404.2.9 limit of 5 pounds of force, so the closer usually needs a look after the seal goes on.
We measure the gap before claiming there was one
Daylight from inside a dark room is a reasonable field test and it is what we use. ASTM E283 air leakage testing is a laboratory method for assemblies, and quoting it as though we performed it on your door would be a misrepresentation.
This work gets bundled into a round
Seal is consumable. It is far better handled as a recurring line on a maintenance visit than as an isolated project every six years, which is how most buildings currently do it.