PVC roofing in Leesburg: when the roof has more to handle than rain
PVC is the welded membrane that makers describe as resistant to oils and grease. It is not our first suggestion for a plain porch roof. This page is about the Leesburg buildings where it fits, and the ones where it does not.
Match what hits the roof to the membrane
| What reaches the roof | What we do about it |
|---|---|
| Grease or oils from a kitchen exhaust fan | Read the maker's chemical statement for the exact sheet. Makers describe PVC as resistant, not immune, and the answer depends on what the fan discharges. |
| Old asphalt flashing or rubberized sealant at a wall | Keep it from touching the sheet. Contact can leach the plasticizer out of flexible PVC, so we separate it with metal or remove it. |
| A dozen pipes, a hatch and a skylight on one roof | Look at factory-fabricated sections and matching boots, which move seam welding off the roof. |
| Nothing but weather, on a small roof | Use something simpler. TPO or EPDM usually meets the need, and PVC would be more than the roof asks for. |
| A pitched visible roof on a house | Wrong family. See metal or shingles. |
Condos, rows and shops: the Leesburg building mix
About 4,200 of the town's roughly 17,000 housing units sit in buildings with five or more units, and another 4,994 are attached townhouse-type homes. Those are the buildings most likely to have one roof over several owners, a board that has to approve the work, and plenty of penetrations. Potomac Crossing alone mixes 385 townhomes with 536 houses, and Exeter adds 430 townhouses beside its single-family homes.
On the commercial side, the Leesburg Premium Outlets sit at 241 Fort Evans Road NE, a road that Battlefield Parkway crosses. If a tenant's kitchen vents onto a roof, that is when the membrane conversation starts. Most of our work is on houses, so PVC is a smaller part of what we do.
Five things to ask any PVC maker or installer
- How thick is the sheet, and how thick is the PVC film above the reinforcing scrim?
- Is the sheet adhered, mechanically fastened or induction welded, and why that choice for this deck?
- What does the chemical resistance statement say about our exhaust?
- What touches the sheet, from old roofing to insulation, and does the maker allow it?
- What is the guarantee, who issues it, and does it come through an applicator the maker approves? Get the terms in writing.
A good answer names documents, not adjectives. We would rather hand a board the maker's own sheets than a sales page, and on any roof we take the same precaution before welding: weathered or dirty membrane is cleaned first.
Two typical Leesburg PVC projects
A one-story retail strip with a tenant kitchen
The roof is about 4,000 square feet. Staining spreads downwind of one exhaust fan, the curb flashing has cracked and two drains hold water. We would test the insulation for moisture, strip the wet areas, add tapered insulation to move water to the drains and weld a PVC sheet with the maker's boot at the fan curb. The owner gets the maker's chemical statement for the sheet and a written reminder to keep grease from building up under the fan.
An eight-unit garden condo building
The low-slope roof is about 3,600 square feet with a dozen pipes, two hatches and old rubberized flashing at the parapet. The board wants one guarantee for the building. We would remove the old flashing or isolate it with metal, order prefabricated pipe boots, and lay the sheet in welded runs. The board receives a written scope, photos of each stage, and a walk-through at the end. Residents get notice of the days we expect noise.
Offices and approvals for a larger roof
Loudoun County issues the building permits inside the Town, and the Town issues zoning permits. The state exemption that covers many house re-roofs names house groups. For bigger multi-family or commercial roofs, the clear exemption is 100 square feet or less of covering, so we expect to ask for a permit and we confirm with Loudoun before we start. No roof-specific Leesburg rule is published that we could find.
Associations have their own approvals, which both the Town and the county tell owners to obtain. Our commercial roof maintenance checklist and guide to choosing a flat roofing company help a board prepare its questions.
Frequently Asked Questions
What should a shop owner ask before any membrane goes under a tenant's kitchen fan?
Ask for the maker's chemical resistance statement for that exact sheet and describe what the fan discharges. One PVC maker states its membrane is inherently resistant to oils and grease, another lists enhanced chemical resistance, and one TPO maker states resistance to restaurant exhaust emissions. Resistance depends on the product and the exposure, so get the statement in writing and keep the fan's grease containment clean.
Can new PVC touch the old rubberized flashing along a parapet?
Not directly. One maker warns that rubberized asphalt can pull plasticizers out of flexible PVC, which leaves the sheet brittle and prone to cracking. The usual cure is to separate the two with metal or a compatible sealant, or to remove the old flashing. Whether PVC can touch polystyrene insulation or old bitumen varies by maker, so we check that before we order.
What is a prefabricated PVC roof, and does it help a roof with many pipes?
Some makers fabricate custom sections in a factory, with the seams already welded, and ship them to the roof. That cuts down on field welding and can come with matching boots for pipes and curbs. It helps most where a roof has many penetrations, though sections must still be welded to each other on site. It is one option, not a requirement for PVC.
Our condo board wants to know who checks the roof when it is done. What do we tell them?
If a building permit applies, Loudoun County does the inspections. If a manufacturer guarantee is part of the deal, the maker may also inspect before issuing it. On our side, we walk the finished roof with the board, photograph the welds, flashings and drains, and give the board the maker's instructions for the sheet. We would not describe any inspection as a promise of how long the roof lasts.
For a condo roof in Leesburg, is the Town or Loudoun County in charge of permits?
Loudoun County's Department of Building and Development issues all building permits for properties inside the Town. The Town of Leesburg issues zoning permits and reviews historic district work. The state exemption that covers many house re-roofs names house groups, so for a larger multi-family or commercial roof we expect to ask Loudoun for a permit, and we confirm that before we start.
Condo and shop roof questions from the Loudoun side
We answer PVC questions from boards and owners in the Town and from Ashburn and Lansdowne, which are outside it in unincorporated Loudoun. Route 7 and the Leesburg Bypass are the roads to plan material deliveries around. Property managers can send a roof plan or a few photos first. See the service area page.
Managing a building with a tricky roof?
Send the address, a rough roof size, a note on anything that vents onto it and photos of the parapet. We will tell you whether PVC fits. Call (571) 453-6515.
Book a Phone Consultation