Montgomery County · MD

Home Additions in Olney

An addition is the one project where zoning can stop you before design starts. We are a licensed contractor in Maryland (MHIC #111971) — we pull the permits through the Montgomery County Department of Permitting Services, coordinate the licensed trades, and hand you a written line-item scope before demolition starts.

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Permits & inspections in Montgomery County

The paperwork is the part most contractors gloss over.

An addition starts with zoning, not construction: setbacks, lot coverage and height limits get reviewed before a building permit is issued, and in some neighborhoods there is a stormwater or historic review on top. Then come the footing and foundation inspections, which have to pass before backfill. This is the longest-lead permit of any project we do, and it is why we start the paperwork while the design is still being drawn.

Your Olney permit goes through the Montgomery County Department of Permitting Services. We pull it under our license and we hold the inspection schedule — you do not chase inspectors and you do not sign the application.

Local to Olney

Olney sits at the edge of Montgomery County's water and sewer envelope, and properties beyond it are on well and septic. If your project adds a bedroom — a basement bedroom or an addition — septic capacity can govern whether it is permittable at all, since systems are sized by bedroom count. Parcels bordering the county's Agricultural Reserve also carry their own zoning constraints on what can be built.

What we find in Olney homes

The house decides half the scope.

Olney is mostly later-20th-century subdivision housing on generous lots, and most of those neighborhoods have an HOA with architectural review for exterior work.

What's included
  • Zoning, setback and lot-coverage review before design is finalized
  • Footings placed below the regional frost line
  • Footing and foundation inspections passed before backfill
  • Roofline, siding and HVAC tied into the existing house so it does not read as an add-on
Planning range — Montgomery County
$180 – $340 / sq ft

A planning range, not a quote. Your written line-item price comes after a free on-site walkthrough. HVAC, electrical and plumbing are performed by licensed trade partners.

2083220833BrookevilleSandy SpringAshtonRockville

Free Olney walkthrough

A written, line-item scope for your home additions project. No design fee, no obligation.

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Also in Olney

One contractor for the rest of the house

Our Olney crews cover Brookeville, Sandy Spring, Ashton, Rockville and every ZIP in the area — 20832, 20833.

Olney home additions questions

Straight answers

Do you handle home additions in Olney, MD?

Yes. United Developers is a licensed contractor in Maryland (MHIC #111971) and works throughout Olney and Montgomery County, including 20832, 20833 and nearby Brookeville, Sandy Spring, Ashton.

Who pulls the permit for a Olney home additions project?

We do, under our license, through the Montgomery County Department of Permitting Services. An addition starts with zoning, not construction: setbacks, lot coverage and height limits get reviewed before a building permit is issued, and in some neighborhoods there is a stormwater or historic review on top. Then come the footing and foundation inspections, which have to pass before backfill. This is the longest-lead permit of any project we do, and it is why we start the paperwork while the design is still being drawn.

Is there anything specific to Olney I should know?

Olney sits at the edge of Montgomery County's water and sewer envelope, and properties beyond it are on well and septic. If your project adds a bedroom — a basement bedroom or an addition — septic capacity can govern whether it is permittable at all, since systems are sized by bedroom count. Parcels bordering the county's Agricultural Reserve also carry their own zoning constraints on what can be built.

What does home additions cost in Olney?

Most Olney projects land in the $180 – $340 / sq ft range. That is a planning range for Montgomery County, not a quote — your written price comes after a free on-site walkthrough.

Is the Olney walkthrough and estimate free?

Yes. The walkthrough and the written scope are free and yours to keep whether or not you hire us. There is no design fee and no consultation invoice.

How long does an addition actually take?

The build is rarely the long part — permitting and zoning review are. Expect the approval phase to run in parallel with final design, and expect us to give you a schedule that names the permit milestone rather than hiding it. We will tell you at the walkthrough if your lot has a setback or coverage problem, because that changes the whole conversation.

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