Shaded north walls and tree cover in Ann Arbor grow mildew and green algae on siding, decks and walks. Washing clears that, along with the chalk on old aluminum siding. It is also the first step of any exterior paint or stain job. Pressure is kept low on wood and old paint, and the surface is left to dry before coating.
Ann Arbor is a city of big trees, and the shade they give has a cost. Siding on the north side of a house turns green with algae. Roof runoff leaves dark streaks. Brick steps and concrete walks grow a slick film, and decks go gray. Older aluminum siding also sheds a white chalk as its factory finish breaks down. Washing removes all of this. People book it as a yearly clean-up, before selling a house, or as the first stage of a paint or stain job.
More pressure is not better. A strong jet held close will gouge cedar, raise the grain on deck boards, force water behind lap siding and blow old mortar out of brick joints. On houses we mostly use a cleaning solution, time for it to work and a low-pressure rinse, often called soft washing. Concrete drives and walks can take more force. Windows, outdoor outlets and light fixtures are protected, plants are rinsed with clean water before and after, and we avoid aiming up under the siding laps.
On a house built before 1978, washing flaking paint can spread chips that may contain lead, so loose paint there is dealt with by hand over ground sheets instead. If painting follows the wash, the surface needs dry weather before primer goes on. Wood takes longer than vinyl or metal. Washing is done in the warmer part of the year, since water left in joints should not freeze. We look at the surfaces, tell you what washing will and will not remove, and give a written quote.
Power washing in Ann Arbor: common questions
Is pressure washing safe for old wood siding?
With low pressure and a wide spray, yes. High pressure is not. It cuts into soft wood and drives water behind the boards. On old clapboard and shingle we rely on cleaner and a gentle rinse.
What is the green film on the north side of my house?
Algae, usually with some mildew. It grows where the wall is shaded and slow to dry. A cleaning solution kills it and a rinse takes it off. Trimming branches back from the wall slows its return.
How soon after washing can my house be painted?
When the surface is fully dry. Vinyl and aluminum dry within a day in good weather. Bare or weathered wood can need two or three dry days, and longer after heavy rain.
How it works
- Free estimate: Call, text or book online. We walk the job and measure.
- Written quote: Prep, paint and price in writing.
- Prep & protect: We cover floors and furniture, repair and prime surfaces.
- Paint & walk-through: Two coats, clean lines, full clean-up and a final walk-through.