EPDM Roofing in Bethesda, MD: Which Energy Code Reads Your Roof?
A condo tower, an apartment block and a corner office building in Bethesda do not fall under the same energy rulebook as a house. Montgomery County changed one roof clause in that rulebook, and a rubber roof sheet comes in black and in white.
Two questions first
Follow your building down the page
What the county printed
One line in Executive Regulation 13-24 moves a zone
The Department of Permitting Services says the 2021 energy code applies to residential applications and four-story townhouses, while "ASHRAE 90.1 - 2022 has been adopted with amendments and replaces the IECC for commercial construction." Its code page titles that standard as the one for "Buildings Except Low-Rise Residential Buildings." A high-rise condo is on the commercial side of that line.
Section 5.5.3.1.4. Roof Solar Reflectance and Thermal Emittance. Delete and replace "Zones 0 through 3" with "Zones 0 through 4". Delete Option "c".
Montgomery County Executive Regulation 13-24, energy amendments to ASHRAE 90.1-2022; effective December 10, 2024; checked 2026-10-11.
The comparison is worth knowing. The model energy code's own roof reflectance table names only Climate Zones 0 through 3. The county's edit goes one zone further, which is why generic advice that "reflectance is a hot-climate rule" does not settle a Bethesda question.
Why EPDM raises it
Same rubber, two sheet colours, one question for the plan reviewer
What the sheet is
EPDM is listed in the building code to ASTM D4637. Trade guidance says sheet membranes come in black and white and many other colours, so the word EPDM on a proposal does not tell anyone how reflective the roof will be.
What the paperwork needs
The Cool Roof Rating Council keeps a public directory of measured values and says it leaves the meaning of "cool" to the code bodies. A listing is a number; whether the number satisfies the county is the county's call.
Same regulation, other roof lines
Snow load and the taller neighbour
The same regulation says design ground snow loads in Montgomery County "must not be less than 30 pounds per square foot," and that all roof areas must be designed for roof snow loads. Where a higher roof or structure is proposed, the applicant has to serve notice on the adjoining owner that "the existing lower roof must be evaluated," not less than 10 days before work starts. In a downtown block where a flat roof sits beside a taller building, that sentence is worth reading. Whether it reaches a membrane replacement with no new height is a question the text does not answer.
Open questions for the county
What to ask the Department of Permitting Services
| Question | Why it is open |
|---|---|
| Does Section 5.5.3.1.4 apply to replacing the membrane on an existing building? | The regulation prints the change but not the scope of the clause. |
| What was Option "c," and what remains? | The county struck it without describing it. |
| How is the rated value to be shown on the plans? | The Cool Roof Rating Council leaves the definition of "cool" to the code body. |
| Does a re-cover over the old sheet count as the same project? | The building code treats a replacement down to the deck differently from a recover. |
The county number is MC 311, 240-777-0311. The commercial side of the Department of Permitting Services handles these energy questions, not the Wheaton house counter.
What happens next
Three steps before a roof sheet is chosen
1. Get the text
Open the Executive Regulation 13-24 PDF and the ASHRAE 90.1-2022 clause it edits.
2. Ask the office
Send the four questions above to the commercial staff and keep the reply.
3. Then the colour
Ask for the product's rated value from its CRRC listing before the sheet is specified.
FAQ
Rubber roofs on Bethesda apartment and office buildings
Is black EPDM allowed on a Bethesda condo roof?
The county printed a change to a reflectance clause but not the clause itself, so only the commercial staff can say how it reads for your roof. Ask them before the sheet is ordered.
Does the county rule apply in Kensington or Chevy Chase?
The regulation is a county one. Those towns have their own approval order, covered on the Bethesda page, so ask the town as well.
Does a white sheet automatically comply?
No. The measured value on the product listing is what a reviewer reads, and the county decides what counts.
Is my four-story townhouse group covered?
The county page says the 2021 energy code applies to four-story townhouses, so this commercial standard is not the one described here.
Does replacing all layers differ from a re-cover?
The building code defines roof replacement as removal of all layers down to the deck and sets limits on recovers, including a water-soaked base. Whether the energy clause cares is one of the questions above.
What if wet insulation is found under the sheet?
The roofing association advises core cuts before re-covering over existing insulation, to learn whether it can dry. A sample from the roof is better evidence than a guess.
Where do I read the county's text myself?
The county's commercial building codes page links Executive Regulation 13-24, and the energy amendments are in that PDF.
Nearby
Other pages beside this one
The Bethesda page holds the permit table and approval order. Membranes are compared on the flat roof page. A different city rule on the same sheet colour question is on EPDM in Rockville, and a Virginia contrast is EPDM in Reston.
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
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