Top-Rated Pressure Washing & Exterior Cleaning in Foster City, CA
Foster City's lagoon-front homes sit right at the water, and that extra ambient humidity is ideal for algae on shaded siding and waterside hardscape.
Peninsula Exterior Care is a 5-star rated, fully insured professional exterior cleaning company based in Atherton, serving Foster City and the surrounding Peninsula. We hold a 5.0 rating across 26 Google reviews, we are insured, and we match the cleaning method to each surface rather than running one pressure setting across an entire property.
Peninsula Exterior Care provides pressure washing, house washing and soft washing, roof cleaning, window cleaning, gutter cleaning, solar panel cleaning, and driveway and concrete cleaning throughout Foster City. We are based in Atherton and match the method to the surface rather than running one setting across an entire property.
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Exterior cleaning services in Foster City
Every surface outside a home wants a different method. Here is how we approach each one, and what it usually involves on a Foster City property.
Pressure Washing in Foster City
Not everything outside a house should be pressure washed, and knowing where the line falls is most of the job. In Foster City we use genuine pressure on driveways, walkways, patios and other hard flatwork, and switch to low-pressure soft washing the moment we move onto siding, stucco, painted wood or a roof. Same visit, two different methods.
House Washing & Soft Washing in Foster City
Most of what makes a Foster City house look tired is organic: algae, mildew and mould growing where shade and moisture sit longest, usually north-facing walls and anything under tree cover. Soft washing removes it properly because the solution kills the growth rather than knocking the top layer off, which is why results last a year or more instead of returning within weeks.
Roof Cleaning & Organic Growth Removal in Foster City
Roof cleaning in Foster City is about organic growth, not dirt. Dark streaking on asphalt shingle is typically algae feeding on the limestone filler in the shingle, and moss establishes in valleys and along shingle edges where debris holds moisture. We use low-pressure soft washing with a roof-safe solution. Pressure is never appropriate on a roof: it strips the protective granules off asphalt shingle and cracks tile, and it is usually what voids a manufacturer warranty.
Window Cleaning in Foster City
Exterior window cleaning here deals with more than dust. Spring pollen bonds into a film, coastal and bay air leaves its own deposits, and hard water from irrigation builds mineral spotting season after season. We clean glass, frames, sills, tracks and screens, and we will tell you honestly when long-term etching will improve substantially rather than disappear.
Gutter Cleaning in Foster City
Roof and gutter cleaning go together on most Foster City homes, because the debris in the gutter came off the roof and the algae streaking on the siding is often runoff from the roof above. Doing both in one visit costs less than two mobilisations and gets a better result than either on its own.
Solar Panel Cleaning in Foster City
Solar panel cleaning matters in Foster City because of how long the dry season runs. From roughly May to October there is little rain to rinse anything off, so dust, pollen and airborne particulate accumulate uninterrupted for months. We use soft brushes and filtered water — nothing abrasive, and nothing that leaves mineral spotting on the glass as it dries.
Driveway Cleaning in Foster City
Concrete and pavers are not the same job. Concrete takes real pressure; pavers have joint sand holding the surface together and lose it under too much force, which loosens the surface and opens the gaps to weeds. Paver driveways in Foster City get controlled pressure and, where it is worth doing, fresh joint sand afterward.
Concrete & Sidewalk Cleaning in Foster City
The white chalky bloom that appears on Foster City concrete is efflorescence — mineral salts moving through the slab — and it is worth being straight about: it can be reduced but it recurs, because the cause is moisture inside the concrete rather than on it. Organic staining, by contrast, comes off properly and stays off for a season or more.
Patio & Deck Cleaning in Foster City
Patio and deck cleaning in Foster City covers wood, composite, paver and concrete, and each needs a different setting. Wood splinters and loses stain under pressure, composite has a textured surface that holds mildew and a manufacturer pressure ceiling, and pavers lose joint sand. Getting this wrong turns a cleaning job into a refinishing job.
Commercial Exterior Cleaning in Foster City
For Foster City commercial property, a recurring schedule usually costs less per visit than letting buildup accumulate for a year and then reversing it. Monthly or quarterly walkway and entry cleaning keeps a property consistently presentable, and we can quote by building or as a property-wide scope for HOAs and multi-unit sites.
What we commonly see on Foster City properties
Built on filled land around a lagoon system, Foster City has consistently higher ambient moisture than inland Peninsula cities. Waterside elevations and shaded siding grow algae faster, and homes here often run on a more frequent cleaning cycle as a result.
Common exterior cleaning problems in Foster City
The common exterior problems on Foster City properties fall into two groups: organic growth, and staining. Organic growth is alive and needs killing rather than blasting. Staining — oil, rust, tyre marks, mineral deposits — needs the right pre-treatment for the specific stain rather than more pressure. Not every property has all of these — but most have two or three.
- Algae, mould and mildew on siding. Usually worst on north-facing elevations and anywhere under tree cover, where surfaces stay damp longest.
- Roof streaking, moss and lichen. Dark streaks on asphalt shingle are typically algae; moss and lichen establish in valleys and along shingle edges where debris holds water.
- Black staining on shaded concrete. Organic film on walkways and driveway edges. It is also slippery when wet, which makes shaded flatwork a safety issue as well as an appearance one.
- Tree-related buildup. Sap, leaf litter, seed pods and needles feeding growth on roofs, in gutters and across hardscape.
- Oil and tyre staining on driveways. Oil soaks into porous concrete rather than sitting on it, so it needs a degreaser and dwell time, not just pressure.
- Spider webs, nesting and entry grime. Eaves, porch ceilings, light fixtures and entryways — the details people see from two feet away.
How we clean different exterior surfaces
The single biggest decision on any exterior job is how much force a surface can take. Here is how we match method to material.
| Surface | Method we use |
|---|---|
| Stucco | Porous and absorbent. Soft wash only — pressure can drive water behind the surface and open hairline cracking. |
| Vinyl siding | Low-pressure soft wash, worked top-down. Panels overlap, and water forced behind them does not drain or dry well. |
| Painted & wood siding | The gentlest setting we use. Pressure furs the grain and lifts paint unevenly. |
| Fiber cement | Tolerates more than wood but still gets a soft wash rather than pressure. |
| Asphalt shingle roof | Low-pressure soft wash. Pressure strips the protective granules and typically voids the manufacturer warranty. |
| Concrete & clay tile roof | Low pressure, deliberate foot placement on the structural high points of the tile profile. |
| Concrete flatwork | Genuine pressure with a rotary surface cleaner for an even finish, plus pre-treatment on organic growth. |
| Pavers | Controlled pressure to protect joint sand, with fresh sand afterward where it is worth doing. |
| Wood & composite decking | Low pressure with the grain. Composite has a manufacturer pressure ceiling worth respecting. |
| Glass, screens & solar | No pressure. Soft brushes and filtered water so the glass dries without mineral spotting. |
Read the full explanation: pressure washing vs soft washing →
Recent work across the Peninsula
Real photographs from our own jobs — full frames, before and after, nothing cropped to make the angles line up.
Why Foster City homeowners choose Peninsula Exterior Care
We work in Foster City regularly rather than passing through. That means we walk the property with you first, use the method each surface actually needs, and tell you honestly when something — old oil, long-set hard water etching, efflorescence — will improve rather than disappear.
Made appointment for 9AM, my clock chimed followed by the doorbell. I expected them to arrive only with a bucket, sponge and squeegee, instead they had state of the art equipment mounted in their vans. The final rinse went through a step to eliminate any water spots and leave the windows sparkling clean. Professional, polite and efficient. A terrific find recommend them to anyone that has similar projects.
Peninsula Exterior Care did an awesome job with our exterior windows. Habib was super professional and courteous. He explained what he was gonna do and was done in time. They have a water softener system and the windows clean out squeaky clean.
We don't always get our windows cleaned, but when we do it will be Peninsula Exterior Care :)
Exterior cleaning FAQs — Foster City
Do you remove algae, moss and mildew?
That is the majority of what we do. All three are living organic growth, which is why we soft wash with a solution and dwell time rather than relying on pressure. Killing it at the root is the difference between results that last a year and results that last a month.
How soon can you get out to Foster City?
Usually within a few days of booking. Autumn gutter season and spring are our busiest stretches, so book earlier in those windows if you need a specific week.
Do I need to be home during the work?
Not usually, as long as we have access to the areas being cleaned and an outdoor water spigot. Plenty of jobs happen while the homeowner is at work.
Is soft washing safe for my landscaping?
Yes. Plants near the work area are pre-wet before we start and rinsed thoroughly afterward, and anything particularly sensitive gets covered. Tell us about it when we walk the property.
How much does pressure washing cost in Foster City?
It depends on the property rather than the city — square footage, number of storeys, the surfaces involved, how long it has been since the last clean, and access. We do not price by city, and we do not quote a range sight-unseen. Send a few photos or book a walkthrough and you will get a real number, usually the same day.
Is pressure washing safe for stucco?
High pressure is not. Stucco is porous, and pressure can force water into and behind the surface and open up hairline cracking. Stucco gets a soft wash: low pressure plus a detergent that breaks down algae and mildew chemically, with dwell time doing the work.
Should vinyl siding be pressure washed or soft washed?
Soft washed. Vinyl panels overlap, and water driven behind them at pressure does not drain or dry, which is how you end up with mould inside a wall cavity you cannot see. Low pressure and the right solution clean it more thoroughly anyway, because they kill organic growth at the root.
Can pressure washing remove black stains from concrete?
Usually yes, when the black is organic growth — which on shaded Foster City flatwork it typically is. We pre-treat so the growth is killed rather than knocked back, then surface clean. Mineral efflorescence is different: it can be reduced but it recurs, because the cause is moisture inside the slab.
Can you remove oil stains from a driveway?
Partly, and how much depends on age. Fresh oil usually comes out well. Oil that has been soaking into porous concrete for years typically lightens substantially rather than disappearing completely. We will tell you what to realistically expect before starting, not after.
Areas we serve near Foster City
Why homeowners choose us
What makes Peninsula Exterior Care a top-rated exterior cleaning company in Foster City?
We hold a 5.0 rating across 26 Google reviews, we are a professional exterior cleaning company based in Atherton, and we are fully insured. Every quote is walked with you before work starts, and we match the cleaning method to each surface — soft washing for siding, stucco and roofs, controlled pressure only where a surface can safely take it.
Are you a professional and insured exterior cleaning company?
Yes. Peninsula Exterior Care is insured and we are happy to provide current documentation before work begins. We are an established local company serving the Peninsula, and we bring the same crew and the same standards to every property we work on.
How do I choose a reliable pressure washing company in Foster City?
Look for three things: verifiable reviews rather than claims, a company that explains which method it will use on each surface, and honesty about what will not fully come out. Old oil in concrete, long-set hard water etching and efflorescence all improve rather than disappear — any company promising complete removal is overpromising.
Do you serve Foster City regularly, or only occasionally?
We work in Foster City regularly. We are based in Atherton and cover the Peninsula, South Bay and San Francisco, so this is an area we are in rather than travel to occasionally.
Free quote for your Foster City property
Send a few details — or a couple of photos — and we'll come back with a price, usually the same day.


