Painting looks like the most straightforward trade and produces a disproportionate number of disappointed homeowners, almost always for the same reason.
Preparation is the job
The visible part of painting is applying paint. The part that determines how long it lasts is everything before that.
Washing to remove dirt, chalking and — in Western Washington — the algae and mildew that grow on shaded elevations. Scraping and sanding failed paint back to sound material. Addressing rot rather than painting over it. Filling and caulking. Priming bare substrate and any stained areas.
A quote that allocates most of its labour to preparation is describing a job that will last. One that goes straight to application is describing one that will not.
The dry window
Exterior paint needs a dry substrate and dry conditions during application and curing. In Western Washington that compresses the season considerably.
The important point is that the surface must be genuinely dry, not merely dry on the surface after recent rain. Timber that has been wet holds moisture below the surface, and painting over it traps that moisture — which then pushes the paint off from behind.
This is why the same crew can produce a ten-year finish in July and a three-year finish in October.
Temperature matters too. Most products have minimum application temperatures, and cool Washington mornings in the shoulder seasons can fall below them even when the afternoon is fine.
Western Washington: mildew and moisture
North-facing elevations and anything shaded by trees grow mildew and algae. Painting over it means it continues growing under the new coating.
Proper cleaning and treatment before painting is essential rather than optional here, and it is the step most often abbreviated.
Moisture from behind is the other failure mode. Paint peeling in sheets rather than flaking usually indicates water reaching the substrate from behind — a flashing failure, a leak, or trapped moisture. Repainting without finding that source repeats the failure.
Eastern Washington: UV
Different problem. Intense sustained sun degrades finishes far faster than anything moisture does in Seattle, particularly on south and west elevations.
Expect to repaint more often than a Western Washington homeowner, and consider that colour choice affects longevity — darker colours absorb more energy and generally degrade faster on sun-exposed elevations.
Interior painting
Less weather-dependent, which makes winter a sensible time for it. Contractors are less busy, and it is work that does not compete for the dry window.
Ventilation matters, particularly in a sealed-up Washington winter house. Moisture and fumes need somewhere to go.
Address the cause before painting over stains. A recurring ceiling stain painted over will recur, because the water is still arriving.
Older homes and lead
A genuine consideration in Washington’s substantial pre-war housing stock. Homes built before lead paint was prohibited may contain it, and disturbing it through sanding or scraping creates a real hazard.
There are specific requirements around renovation work disturbing lead paint in older homes. A contractor working on pre-1978 housing should know them and be certified appropriately.
If your house is old enough for this to be a question, raise it rather than assuming.
Judging a quote
Ask what preparation is included, specifically. How much scraping and sanding. Whether washing is included. What happens if rot is found. What is being primed and why. How many coats.
Two quotes with the same number of coats can describe entirely different jobs.