Short answer: interior window cleaning is the inside face of the glass, plus the sills and the tracks underneath it. It is booked separately from a standard clean because a Bellevue house with a view wall is not a room with a window in it - the glass is a job of its own. The single thing that decides whether you will be happy with the result is which side of the glass the problem is actually on, and on the Eastside it is very often not the inside. That is the first thing we work out, and we would rather tell you before we start than after.

Work out which side the haze is on before you book anything

An interior clean touches one of the surfaces you are looking through. A modern insulated window has four - the outside face, the two faces sealed inside the unit, and the inside face. So a window can be spotless on our side and still look milky, and the homeowner reasonably reads that as a bad clean.

You can settle it in about ten seconds, before anyone comes out:

Draw a short line on the inside glass with a fingertip. If the mark you can see moves with your finger, the film is on the inside and an interior clean will remove it.
If the haze sits still while your finger moves over it, it is on the outside face or sealed between the panes. Interior cleaning will not touch it, no matter how well it is done.
Check whether it changes with the weather. A film that appears on cold mornings and burns off by afternoon is condensation, not dirt. Which side it forms on tells you two very different stories - see the next two sections.

Do this on the two or three windows that bother you most. It takes a minute and it is the difference between booking the right work and paying for the wrong one.

Fog between the panes cannot be cleaned - and it is common in Bellevue's older housing

A double-glazed window is a sealed unit: two panes held apart by a spacer bar, with a desiccant inside the spacer to absorb the small amount of moisture trapped at manufacture. When that seal fails, outside air cycles in and out with every temperature swing, the desiccant eventually saturates, and moisture starts condensing in the cavity where no cloth can reach.

The tells are consistent:

The haze does not move when you wipe either face.
It comes and goes with sun and temperature rather than with cleaning.
Over time it leaves a permanent tide mark or a faint crazed pattern low on the pane, where minerals from repeated condensation have etched the inner surface.
It is usually worse on one or two panes, not the whole house at once - seals fail individually.

This is a glazing repair, not a cleaning problem. The sealed unit gets replaced, usually into the existing sash and frame. We will point it out, photograph it if that helps you get a quote, and take it off your cleaning scope so you are not paying us to fail at it.

Why the Eastside sees a lot of it: much of Bellevue's detached housing went up from the late seventies through the nineties, so a great many homes here are still on their original sealed units. Large fixed panes on south and west elevations take the hardest thermal cycling - hot afternoon sun, cold clear night, repeated for decades - and that cycling is what eventually works a seal loose. The big view window is both the one you care about most and the one most likely to go first.

Condensation on the inside face is a humidity problem, and cleaning it does not fix it

The other winter complaint is the opposite: water actually running down the room side of the glass. That is not dirt and it is not a failed seal. It is warm, moist indoor air meeting the coldest surface in the room. Clean it and it returns the next cold morning.

It matters because of where the water goes rather than how it looks. It pools along the sill, wicks into the joint between the sill and the frame, and sits in the bottom corners of the reveal - which is exactly where mildew starts on painted trim and where a wrapped MDF sill begins to swell. By the time it is visible as black speckling in the corners, the water has been arriving for months.

What actually reduces it is air and ventilation, not cleaning:

Bathroom and kitchen extract fans that are genuinely run and genuinely vented outdoors rather than into a roof space.
Air movement across the glass - a sofa or a tall headboard pushed against a window wall creates a cold, still pocket that condenses first.
Drying laundry anywhere other than a closed room with a cold window in it.
A dehumidifier in the worst room through the wet months.

We will clean the mildew that is already on the sills and sash corners, and tell you plainly which windows are going to keep doing it. There is more on managing damp through a Pacific Northwest winter in our guide to rainy-season cleaning, mud and mildew.

The tracks and the weep holes are the real work

On a slider or a casement, the glass is the quick part. The track is where the time goes, and it is the part most quotes quietly leave out.

What collects in an Eastside window track is specific: fir and cedar needles, bud casings and catkins in spring, the heavy conifer pollen wash that follows, moss and lichen fragments off shaded siding, and the fine grit that blows in whenever the window is open. Add rain and it stops being loose debris and becomes a paste that sets into the corners.

Underneath that sit the weep holes - the small slots at the outer bottom of the track whose only job is to let water drain back outside. When they silt up, the track holds water instead of shedding it. On a wind-driven Bellevue rain the level rises past the inner lip and the overflow goes into the room side: onto the sill, into the joint, and eventually into the frame. A blocked weep hole is one of the few genuinely damaging things a cleaner can find and fix in a few seconds.

The order matters and it is the thing amateurs get backwards:

Dry first. Stiff brush along the track, then a vacuum crevice tool, until the loose material is out.
Then damp. Detergent and a cloth wrapped over a thin tool for the corners and the channel behind the rollers.
Then clear the weeps and check that poured water actually drains.

Spraying a dirty track first simply makes mud and pushes it into the corners where it hardens. A track that looks worse a week after cleaning was almost always cleaned wet-first.

Film, coatings, and why a razor blade is not our default tool

Interior glass is not always plain glass, and the assumption that it is causes permanent damage.

Applied window film. Aftermarket solar, privacy and UV films go on the room side. Ammonia-based cleaners haze them, abrasive pads scratch them, and a scraper takes them off in a single pass. West-facing view glass in Bellevue is a common place to find it, and it is often old enough that the homeowner has forgotten it is there. If you do not know, tell us that - we will treat the glass as filmed, which is the safe assumption.
Tempered glass. Code puts tempered panes in and beside doors, in low glazing and in large panes - so exactly the ones a cleaner most wants to scrape. Tempered glass can carry fine fabricating debris fused to the surface from manufacture, and dragging a blade across it can leave permanent hairline scratches that are invisible until the low winter sun rakes across them. That is the main reason we do not scrape as a matter of course.
Low-emissivity coatings. On a modern sealed unit the low-E layer is on a face inside the cavity, so normal interior cleaning does not reach it. Worth knowing mainly as a reminder that a window is a layered assembly and not a sheet of glass.

What we actually use is unglamorous and hard to get wrong: a mild detergent solution, a strip washer to carry it, a squeegee to pull it, and a dry cloth for the edges. No ammonia by default, no abrasive pads, and paint or adhesive residue gets flagged rather than scraped unless you specifically want us to take the risk on a pane you have identified.

Why glass streaks, and how we avoid it

Streaking is nearly always process, not product. Four causes cover most of it:

Sun on the glass. Hot glass flashes the solution dry before the squeegee reaches it, and what is left is a dried film in the shape of your last stroke. A west-facing Bellevue view wall is a morning job for this reason alone; the east side of the house is an afternoon job.
Water that has stopped being clean. The last room of a large house looks worse than the first if the solution has been carrying the first room's soil around with it.
Residue from consumer sprays. Anything with silicone, wax or a shine additive leaves a film that reappears every time the pane warms up, and it gets thicker each time it is reapplied. The first proper clean of glass with that history takes two passes - one to strip, one to finish.
Paper towel on a large pane. It sheds lint, drags at the edges, and cannot hold a straight line across a wide sheet. Squeegee for the field, a dry cloth for the perimeter only.

Kitchen glass gets its own note: cooking aerosol lands on it as a genuinely greasy film, and a glass cleaner alone will smear it rather than lift it. It needs a degreasing pass first. If the kitchen is the room that is bothering you, a deep clean that includes the glass is usually better value than glass alone.

A quote is counted in panes, not windows - plus height and access

Four things move the number, and none of them is the room count:

Panes, not windows. One picture window is a single fast sheet. One window of the same size with true divided lites is a dozen small panes, each with four edges that have to be worked by hand and dried individually. It can take several times as long as the flat pane next to it. Grid style is the single biggest predictor of the hours.
Height. Two-storey entry glass, stairwell windows and high transoms need a pole or an indoor ladder set-up, and the stair geometry decides whether either is safely possible. A photo from the floor answers this faster than any description.
Access. A glass wall behind a sectional, a dining table or a wall of plants carries a moving-and-replacing cost that has nothing to do with the glass.
Tracks and sills in or out of scope. After pane count this is the largest swing in the estimate, and it is the item most often assumed rather than agreed.

On screens: interior cleaning does not require removing exterior screens, so we leave them in place unless you ask. Older aluminium frames bend when they are popped out and reseated, and a screen that no longer sits square is a worse outcome than a slightly dusty one. If you do want them out and washed, say so when you book and we will handle them as their own line rather than as an afterthought at the end of the visit.

How often, and what it pairs with

Interior glass in a shoe-free Bellevue household holds up well - twice a year is a sensible baseline for most of the house. The exceptions are the panes that get handled or cooked near: door glass, the slider to the deck, and anything within reach of a range. Those are worth folding into a recurring clean rather than waiting for the twice-yearly pass.

Three moments where it is worth doing properly rather than opportunistically:

After a remodel. Fine drywall and joint-compound dust is abrasive and slightly alkaline. Wiping it dry drags grit across the pane; it has to be flooded and floated off. That is part of post-construction cleaning for exactly this reason.
At a move-out. An empty house means nothing to move and every pane reachable, which makes it the cheapest time this work is ever done. It is included in the scope of a move-out clean.
Before listing or before guests. Clean glass changes how bright a room photographs more than almost anything else you can do to it in an afternoon.

A standard visit deliberately stops at mirrors and spot-cleaning marks on door glass. That is a scope decision, not an oversight - absorbing a view wall into a routine visit would either blow the time or shortchange the rest of the house.

Booking it in Bellevue so the number holds

We quote flat and upfront across Bellevue and the Eastside, which only works if the picture is accurate before the first visit. Tell us four things and the quote we give you is the one you pay:

Roughly how many panes, and whether any windows have grids or divided lites.
Anything above normal reach - stairwell, entry, transoms.
Whether you want tracks and sills included.
Whether any glass has applied film, or that you are not sure.

If you already know some panes are fogged between the layers, flag those too - we will leave them out of the count rather than charge you for glass that cannot improve. There is a short list of things worth doing before any cleaner arrives in how to prepare your home for a house cleaner, and if you are still working out the budget for the wider house, our house cleaning cost guide lays out what drives the price.