EPDM roofing in Manassas, VA: a flat roof that carries a patio, a unit or a railing
The City of Manassas wrote rules for what may stand on a downtown roof, and it wrote them without naming a roof covering. EPDM is one of the sheet membranes a flat roof can take, so the useful question is what the new membrane must work around: the things on top of it.
prints about the roof top
to the roofer
The City's own words
Which things on a downtown flat roof does the guideline book mention?
Read October 15, 2026, from an Internet Archive copy of the City's Historic District Design Guidelines (adopted April 19, 2022), because the City's site blocks automated readers. Page numbers are the printed ones.
| On the roof | What the guidelines print | Roof covering named? |
|---|---|---|
| A rooftop patio | Outdoor dining is "typically found on patios and sidewalks, and rooftops" (p. 166). On a rooftop, minimize visual impact on the streetscape, leave historic features in place and keep views of the patio from street level to a minimum (p. 168). | No |
| The railing | Metal, in a colour compatible with the building; the general patio rule says black (p. 168). | No |
| Tables and chairs | Heavy enough "to not become a public hazard in the event of a strong wind"; polyresin sets are prohibited (p. 168). | No |
| Rooftop enclosure | Patio areas are not to be permanently enclosed or look like a building addition (p. 168). | No |
| HVAC and other equipment | Place mechanical and exterior HVAC equipment "in unobtrusive locations" or screen it (p. 167). | No |
| EPDM by name | The text says membrane and built-up, never a product. We searched the whole PDF for EPDM and found no match. | Ask staff |
A design guideline is not a permit rule
The chapter that holds these lines says some of its elements "do not come directly under architectural review" and that site paving and landscaping are reviewed through the development review process. So a patio plan can sit in a different queue from a re-roof. The guidelines do not say which queue a rooftop patio uses; Planning and Development at 703-257-8278 answers that, and our Manassas page lists the permit desks.
Our reading, not the City's: a metal railing has to be fixed to something, and tables heavy enough to stay put add load. Where posts, units and furniture touch a membrane roof is a roofer's question, so it belongs in the scope before the sheet is chosen.
Does this page describe your building
Is a flat downtown roof what most Manassas homes sit under?
Census Bureau estimates for the city, ACS 2024 5-year (2020 to 2024), occupied homes only. The Census counts units in a building, not roof shape.
- Owner-occupied houses and townhouses9,151 of 10,151 owner homes
That is 5,729 detached and 3,422 attached. The City's roof-shape survey says nearly half of residential buildings have gable roofs with a steep pitch, so for most of these owners a flat-roof page is not the one to read.
- Buildings of 5 to 19 units2,144 occupied units
Owners hold 566 of them and renters 1,578. A renter here does not choose the roof; the owner or the association does, and the unit count says nothing about whether the roof is flat.
- Buildings of 20 or more units1,000 occupied units
Owners hold 225 and renters 775. With the group above, buildings of 5 or more units hold 3,144 occupied homes, 22.1 percent of the city, and 74.8 percent of them are rented.
- Downtown commercial buildingsThe City's own style guide, p. 34
The guide describes the Main Street type as masonry buildings with flat roofs with or without parapets and no setback, and the Industrial type as rectangular masonry buildings. It names two reused ones: the Candy Factory, now the ARTfactory, and the train depot, which houses Historic Manassas, Inc., the Visitor Center and the Railroad Heritage Gallery. It prints nothing about their roofs.
Before a membrane is chosen
What should the roof plan list besides the roof?
- Every unit, curb and pipe, and who owns itA tenant's equipment and the building's are different jobs to move or flash around.
- The patio footprint and where each railing post landsDrawn on the roof plan, so the membrane work and the railing work meet on paper.
- Where the drains and scuppers areWater from rooftop equipment can pond; our flat roof guide covers how.
- The building's designation on the City's listThe TPO page for Manassas reads the membrane and parapet lines of the same guidelines.
Questions
Questions about EPDM, rooftop patios and equipment in Manassas
Do the Manassas guidelines name EPDM?
No. The PDF says membrane and built-up and names no product. EPDM is one of the single-ply sheet types the building code lists; our flat roof guide compares them.
Can a patio go on a Manassas flat roof?
The guidelines have a rooftop dining item with conditions on views, railings and enclosure. They do not grant permission for any address, so ask Planning and Development about yours.
Do rooftop units change an EPDM job?
They change the scope: each unit and curb is something the sheet must be flashed around or the unit moved. The guidelines only say where equipment should sit or be screened.
Why would a railing matter to a roofer?
Our reading: a post has to be anchored, and an anchor on a membrane roof is a spot to detail on purpose. The guidelines say nothing about anchoring.
Does the depot or the Candy Factory appear in the roof rules?
Both are named in the style guide as reused buildings, with no roof detail. We make no claim about what covers either one.
I rent in a five-unit building. Is this my decision?
Usually the owner or association chooses the roof. Ask who that is and whether your building is inside a local historic district.
Does a patio change what the roof needs underneath?
It adds foot traffic, furniture weight and railing anchors. Whether the structure carries them is a question for the building owner and a structural professional, not something this page can answer.
More flat-roof reading: the materials overview and neighboring EPDM pages for Centreville and Woodbridge.
Official pages used
Checked October 15, 2026: the City's Historic District Design Guidelines PDF (archived copy read; printed page numbers) and Census Reporter tables B25032 and B25127.
Talk through the next step
Talk through your roof with King's Roofing
Share the address, what you are seeing on the roof and the decision you need to make. We will tell you what to expect before anything is scheduled.
9220 Topaz St, Fairfax, VA 22031
Mon to Fri 7 AM to 8:30 PM, Sat 7 AM to 8 PM, closed Sunday