19010 · Montgomery County, extending into Delaware County

Residential Exterior Cleaning in Bryn Mawr, PA

Lower Merion, with parts in Haverford and Radnor · Montgomery County, extending into Delaware County · Gutter cleaning, roof cleaning, house washing, solar panel cleaning, patio washing, and pool deck cleaning.

Bryn Mawr has the heaviest concentration of large stone houses in our service area, and stone is the material that punishes the wrong cleaning method hardest. Wissahickon schist laid with lime mortar, stucco applied over masonry, and slate roofing are the three surfaces we see most, and all three are damaged by the high-pressure approach most homeowners picture when they hear power washing.

The other defining feature is the tree cover. The specimen trees around the older estates and near the college create deep, persistent shade, and shaded stone stays wet. That is why algae here shows up as a broad dark cast across a whole elevation rather than as streaking.

Everything we do in Bryn Mawr is low pressure by default. We identify the wall assembly first and set the method to it.

Housing Stock

What we work on in Bryn Mawr

Large stone Colonials and Tudors from the 1900s through the 1930s, stucco-over-masonry, some Victorian frame, and postwar infill on smaller lots. Slate is common on the older roofs; asphalt on the newer. Flagstone and bluestone terraces are close to standard on the larger properties.

Bryn Mawr College campusBryn Mawr station on SEPTA's Paoli/Thorndale LineLancaster Avenue business districtBryn Mawr Hospital area

Local conditions that drive the work here

Schist and lime mortar

The local building stone is Wissahickon schist, historically set in lime mortar. Lime mortar is soft by design so the stone moves rather than cracks, and it will wash out of the joint under a pressure wand. Repointing a full elevation runs into serious money.

Deep specimen-tree shade

Mature beech, oak, and maple around the older properties block direct sun on entire elevations for most of the day. Those walls hold moisture, and the growth is uniform rather than streaked.

Slate roofs at end of a long life

Many Bryn Mawr slate roofs are original. They will last decades more if biological growth is kept off and nobody walks on them. Both of those are achievable; only one of them is achievable with a ladder and a harness.

Stucco over masonry

Older stucco applied over stone or brick behaves differently from modern EIFS. It is more forgiving chemically but no more tolerant of pressure. Staining that has migrated into the finish coat lightens rather than disappears, and we say so before quoting.

Our services in Bryn Mawr, PA

House Washing in Bryn Mawr, PA

The core Bryn Mawr service. Stone with lime mortar and stucco over masonry both get a soft wash with extended dwell time, because the growth on a permanently shaded elevation is thicker than it looks from the driveway.

How our house washing works

Roof Cleaning in Bryn Mawr, PA

Slate first, asphalt second, and both cleaned with no pressure at all. On slate the goal is removing moss from the seams before it lifts a tile. On asphalt it is killing the Gloeocapsa magma causing the black streaking.

How our roof cleaning works

Gutter Cleaning in Bryn Mawr, PA

Half-round copper and older built-in box gutters show up on the larger Bryn Mawr houses, and both need a gentler touch than a standard K-style aluminum run. We inspect by drone first so we know what we are dealing with before anyone reaches the roof edge.

How our gutter cleaning works

Patio & Walkway Washing in Bryn Mawr, PA

Flagstone and bluestone terraces are standard on the larger properties and are softer than concrete. Chemical pre-treatment does the work; the pressure is dialed back so the stone does not fret at the surface.

How our patio & walkway washing works

Pool Deck Cleaning in Bryn Mawr, PA

Shaded pool surrounds grow biological film quickly and get slick. We clean the deck, coping, and steps, and check the wet surface for traction before we leave.

How our pool deck cleaning works

Solar Panel Cleaning in Bryn Mawr, PA

Arrays here are usually tree-shaded, which means a heavy pollen and tannin load. Deionized water only, and no ladder against the array frame or foot traffic on the slate below it.

How our solar panel cleaning works

Bryn Mawr questions

Will washing hurt the mortar on my stone house?

Pressure washing would. Lime mortar is deliberately soft and a pressure wand will erode the joint. We soft wash stone at roughly garden-hose pressure and let the cleaning solution do the work, which leaves the mortar intact.

My whole north side is dark. Will it come back to the original color?

Usually most of the way. Live biological growth clears completely. Staining that has migrated into an older stucco finish coat lightens substantially but may not disappear entirely, and we will tell you which one you have before you commit.

Do you serve the Lower Merion and Delaware County sides of 19010?

Both. Bryn Mawr's 19010 spans Lower Merion in Montgomery County plus parts of Haverford and Radnor townships in Delaware County, and we cover all of it.

Get a quote for your Bryn Mawr home

Send the address and what you are seeing. We come back within 24 hours.