Assign a plan location and photo ID to every penetration
A reroof survey needs a penetration register: a record that connects every pipe, vent, skylight, equipment curb and other roof opening to a marked plan. Start with a unique ID, the roof zone and a dated overview photograph. Add close views that show the flashing and enough surrounding roof to identify the feature later. A folder of unnumbered close-ups leaves the estimator unable to connect a repair allowance to a location.
Use the Roofing Calculator for the separate covering takeoff after confirming roof planes and pitches. Its area result cannot reveal an unrecorded pipe or decide which curb needs alteration. Keep the register beside that worksheet so a complete field-covering quantity does not conceal missing detail work.
Plan safe access before collecting measurements. HSE’s fragile-surface guidance warns that even short maintenance tasks need precautions and prioritizes avoiding exposure where possible. Rooflights and suspect surfaces require a competent access assessment. An aerial photograph can support the register, but it does not establish the condition of hidden supports or make a roof safe to walk on.
Confirm which services remain, move or come out
A penetration’s service status determines the work attached to it. Mark each item as retained, relocated, removed or unresolved, and identify the person authorized to confirm that decision. A capped pipe, silent fan or disconnected-looking cable is not reliable evidence that the service has been abandoned. Check building records and refer the item to the responsible trade.
For a proposed removal, ask for the agreed isolation, removal boundary and roof or deck reinstatement detail. Distinguish removing the visible pipe above the membrane from closing the opening and dealing with equipment below. Gas, combustion, electrical and other active services require the appropriately qualified people; the survey is not permission to disconnect them.
Give unresolved items an owner and a due date before tender clarification or ordering. Otherwise, one contractor may price retention while another assumes removal. The resulting quotes describe different jobs even if both use the same measured roof area. Keep provisional quantities visible until the service decision is approved.
Measure curbs against the proposed finished roof level
A curb is the raised support or enclosure around equipment or an opening. Its exposed height depends on the roof surface beside it. Record the existing roof level, the proposed build-up and the intended flashing termination. Measure on the sides affected by falls or tapered insulation, rather than assuming one reading describes the entire perimeter.
In its 2002 skylight article, NRCA’s Professional Roofing explains that added insulation in a re-cover can reduce available flashing height. The article discusses an 8-inch base flashing height for its low-slope skylight context. Treat that as a documented example, not a universal minimum for every roof or curb. Have the designer verify the selected assembly, equipment instructions and applicable requirements.
Check the height subtraction before pricing a curb extension
Suppose a hypothetical curb termination is 12 inches above the existing roof and the proposed surface rises 3 inches at that location. Available exposure becomes 12 − 3 = 9 inches, or 228.6 mm. This calculation establishes geometry only. It does not approve a flashing detail, prove clearance beneath equipment or account for a different level on the uphill side.
Describe the flashing layers and their condition
Flashing joins a roof covering to a penetration while directing water around the opening. Record the visible membrane, boot or formed flashing, its termination and any counterflashing that protects the upper edge. Include splits, detached edges, corrosion, temporary patches and evidence of water entry. State which layers were visible and which remain concealed.
PNNL’s Building America guide calls for inspecting penetration flashings during reroofing and integrating them with the roof’s water-control layer. Its illustrated examples include pipes, a roof drain, a skylight curb and a solar support. The examples explain continuity across the assembly; they do not make one detail suitable for every membrane, metal panel or shingle system.
Attach the proposed manufacturer detail number and revision when available. If a material cannot be identified, flag compatibility for confirmation before specifying adhesive, sealant or a new flashing. Photographing an old patch is useful evidence of condition, but copying its shape into the new work can repeat an unverified repair.
Record drainage routes and working clearances
The space around a penetration affects how the new roofing can be installed and maintained. Mark nearby drains, valleys, roof edges, walls and other curbs on the plan. Measure congested gaps and show the direction of roof falls. A close photograph should reveal whether the visible detail can be reached without moving adjacent equipment.
PNNL’s roof-penetration guide explains that water-control materials must shed water through appropriate overlaps or sealed continuity. Use the survey to identify locations where drainage and the proposed detail need review. A photograph of staining or debris can prompt investigation, but it cannot prove the cause of a leak or the capacity of a drainage system.
Separate roofing access from equipment-service clearance. Ask the equipment supplier or services designer to confirm required access and operating space. Where insulation, walkways or curb extensions would change that space, record the conflict for resolution. Do not invent a single clearance dimension for vents, flues, fans and skylights.
Separate measured runs from purchased detail materials
A flashing takeoff starts with measured geometry, then applies the approved detail and product coverage. For a rectangular curb, perimeter P = 2 × (length + width), using one length unit throughout. Three hypothetical 4 ft by 6 ft curbs have 20 ft of perimeter each and 60 ft combined. That is a measured run, not a ready-made roll order.
Corners, laps, vertical height, horizontal returns and usable sheet width affect the material requirement. Keep those inputs with the specific detail. Do not multiply the 60 ft by a guessed universal waste percentage and assume every boot, termination and counterflashing has been included. Count proprietary pieces individually where the approved system requires them.
| Survey item | Measured or confirmed basis | Separate pricing item |
|---|---|---|
| Retained pipe | Diameter, location and approved boot detail | Boot, preparation and termination |
| Rectangular curb | Each side, levels and detail revision | Flashing, corners and counterflashing |
| Confirmed removal | Service sign-off and reinstatement boundary | Isolation, removal and roof repair |
| Unresolved feature | Named decision owner and deadline | Explicit provisional scope |
Reconcile the Roofing Calculator result with this detail schedule. The tool uses plane dimensions, pitch, chosen covering allowance and actual product coverage; its listed accessory fields do not include curb flashing. Price removal, service attendance, curb changes, disposal and access separately so their absence cannot be mistaken for a saving.
Issue the register with decisions and unresolved work
Before issuing a reroof survey, check that each plan ID appears in the photographs, measurements and scope. Give the roofing contractor a usable decision record instead of asking them to infer the intention from old patches. Record the designer’s accepted detail and the trade responsible for each associated service task.
- Match plan IDs to dated overview and detail photographs.
- Confirm retained, removed and unresolved service status.
- Show proposed roof levels beside each affected curb.
- List approved details, measured runs and individually counted parts.
- Keep service work, access and provisional items visible in the quote.
Enter verified roof planes and product coverage in the Roofing Calculator, then retain the penetration register as a separate attachment to the order. Revise both records when a service moves or the roof build-up changes. A covering quantity and a resolved detail schedule answer different parts of the reroof scope.
