North America ยท Window Manufacturer
Inline Fiberglass โ Window Cleaning Guide
๐จ๐ฆ Canada ยท Last reviewed by Justin Orloff
Quick Facts
founded
1994
hq
Ontario, Canada
primaryMaterials
Pultruded fibreglass profiles, triple and quad glazing
glazingPartner
In-house glazing; Passive House-certified units available
marketTier
Premium to High Performance
Brand at a Glance
- Founded: 1994
- HQ: Ontario, Canada
- Market position: Premium fibreglass windows for Passive House and high-performance residential
- Primary material: Pultruded fibreglass
- Thermal coefficient: Fibreglass expands at the same rate as glass - minimal seal stress through temperature cycling
- Climate context: Ontario - freeze-thaw cycling, extreme cold, hot humid summers
- Certifications: ENERGY STAR, Passive House PHI certification, CSA
- Website: inlinefiberglass.com
Product Range
- Pultruded Fibreglass Casement Windows
- Fibreglass Awning Windows
- Fibreglass Fixed Windows
- Fibreglass Doors
Why This System
Pultruded fibreglass has a thermal expansion coefficient almost identical to float glass - approximately 9 x 10-6 per degree Celsius for both materials. This means the frame and the glass unit expand and contract together, dramatically reducing stress on the edge seal through freeze-thaw cycling. Because fibreglass and glass move together, the perimeter seal on Inline windows is under less cumulative fatigue than the same seal on a uPVC or aluminium window in the same climate. However, the seal still needs inspection - it is not immune to failure. Fibreglass profiles are paintable and often left in factory colours - white, grey, bronze, and black are common. The factory finish on fibreglass is applied differently from powder-coat on aluminium and responds differently to cleaners. Passive House windows are extremely airtight. The frame-to-wall interface is carefully detailed with membranes and tapes that are part of the building airtightness layer. Window cleaning should never involve pressure washing or water application at the frame perimeter - protecting the airtightness membrane is a professional obligation on these buildings.
Step 1 of 2: Manufacturer Recommendations
Official Care Guidance
Step 2 of 2: The Orloffs Protocol
The Orloffs Protocol
Since 1999 I've cleaned hundreds, if not thousands, of different window brands and systems. The physics of clean glass don't change from one brand to the next. Follow the steps below and you'll clean your Inline Fiberglass windows to a professional standard โ guaranteed.
Pro Tools
My daily tool list. This is what I carry to every job.
Follow these steps in order. Each one builds on the last. This is the same sequence I use on every Inline Fiberglass installation.
- 1
Preparation -- before any water touches the glass
Fill the bucket with at least 10 litres of water. Add soap for cleaning power -- enough to cut through environmental deposits, not so much you are fighting foam.
Before touching the glass, brush down the surface to remove loose dust, spiderwebs, and debris. Any grit left on the glass during the wash phase risks scratching during agitation.
Check the fibreglass frame condition before you start. Confirm which cleaning product is safe for that surface before opening any bottle.
Cover anything below the windows that cannot be moved.
- 2
Agitation -- apply and work the solution
Dip the microfiber T-bar completely into the soap water, both sides. Remove excess water with your hand so it does not drip. Apply the solution across the entire glass surface with overlapping passes.
The goal is to fully dissolve and release every deposit from the glass surface. Anything not released during agitation gets transported across the glass by the squeegee as a smear.
For stubborn spots -- insect marks, salt residue, environmental deposits -- re-apply soap water and allow it to soak for a full minute before agitating again. Use more soap water, not more pressure.
For panels above arm reach: attach the T-bar to an extension pole. Work in sections -- top first, then middle, then bottom -- keeping each section wet until you squeegee it.
Rinse the T-bar cover regularly during the job. A dirty applicator causes microscopic scratches that accumulate over time.
- 3
Detail the frame edge before squeegeeing
Use your 100% cotton towelling rag, finger pressed into the fabric, to work into every junction and remove pooled soap water before the squeegee pass.
This prevents drips running down onto already-cleaned areas during squeegeeing and keeps soap water out of drainage channels.
On Inline Fiberglass fibreglass frames, pay particular attention to the bottom edge where glass meets the frame sill -- water pooled here runs into drainage openings and leaves residue over time.
- 4
The squeegee
Tilt the squeegee at a slight angle so soap water spills from one side of the channel only -- not both. If the rubber is jumping or squeaking, either the rubber is not lubricated enough or the glass surface has warmed.
Cutting in: start with the rubber blade making first contact on a dry edge of the glass.
Side to side: horizontal passes across the panel. Works well on wide sections. Top to bottom: vertical passes down the panel. Works well on tall narrow sections.
The J tune: one smooth unbroken motion top to bottom, wrist rotating at each end to reverse without lifting the rubber. The most efficient method on larger panels -- but it requires training before applying it to premium glass.
Wipe the rubber dry after every pass. Overlap each stroke by 2-3 cm.
- 5
Final edge detailing
After squeegeeing, there is always a residual line of water along the bottom edge and at the panel sides. Take a dry cotton rag, fold to a clean corner, and detail these edges in one smooth pass.
On Inline Fiberglass frames, the bottom edge where glass meets the sill requires the most careful attention. Water left here runs into drainage and leaves residue that affects the next clean.
Rotate the rag to a clean section after every pass. If the rag picks up grit at any point, replace it immediately.
- 6
Frame wipe and hardware check
On Inline Fiberglass fibreglass frames: pH-neutral cleaner, soft cloth only. Fibreglass is scratch-resistant but coatings are not -- never use abrasive materials.
Check that all drainage openings are clear and unobstructed. Water must be able to flow freely -- a blocked channel leads to accumulation that affects seal performance over time.
Operate every opening window through its full range. Stiff handles or resistance at locking points indicate hardware that needs lubrication. Flag it to the owner rather than forcing it.
Pro Tips
- Ask the client or site manager whether the windows are Passive House certified before your first visit - it changes the protocol significantly, particularly around frame-perimeter water application
- On quad-glazed units, the glass is exceptionally heavy. Use a squeegee handle with a locking channel retention system - a blade that pulls out mid-stroke on heavy glass leaves a dragged smear that is hard to correct
- Fibreglass frames clean up with less effort than aluminium frames in hard-water areas - fibreglass does not bond with calcium deposits the way anodised aluminium does. A simple pH-neutral wipe is usually sufficient
What NOT To Do
- Do not use razor blades on glass without confirming no inner-face Low-E or solar control coatings are present - Passive House glazing almost always has multi-layer coatings
- Do not use solvent-based cleaners on painted fibreglass frames
- Do not pressure-wash the frame perimeter - Passive House airtightness membranes at the frame-to-wall junction must not be disturbed
- Do not use abrasive pads on fibreglass frame surfaces - the factory finish coat is not indestructible
- Do not apply water at the frame-to-wall junction on Passive House installations
Bundle Kits and Tool Recommendations
Bundle Kit
Cleaning Frequency
Clean every 4โ8 weeks depending on environment.
Frequently Asked Questions
Field Notes
โPassive House buildings are often occupied by clients with high awareness of building performance. They notice problems. A cleaning visit that disturbs the airtightness membrane at the frame perimeter is a significant issue - more so than on a standard residential window. Fibreglass frames do not yellow with age the way early uPVC did. However, in high-UV positions, the factory paint or pigment coat can fade unevenly. Document any uneven fading at the first spring visit. The narrow frame profiles on Inline fibreglass windows mean the sill is also narrow. Less drainage capacity than a wider uPVC sill. Spring melt and heavy rain can exceed the sill capacity if drainage slots are blocked - always clear sill drainage before the spring wet season.โ
Justin Orloff
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