
Asia-Pacific ยท Glass Manufacturer
Nippon Electric Glass โ Window Cleaning Guide
๐ฏ๐ต Japan ยท Last reviewed by Justin Orloff
Quick Facts
founded
1944
hq
Otsu, Japan
primaryMaterials
Specialty and technical glass - fire-resistant, borosilicate, functional glass
glazingPartner
Supplied to window system manufacturers for specialty applications
marketTier
Specialist Commercial
Brand at a Glance
- Country: Japan
- Founded: 1944
- Speciality: Technical and specialty glass - fire-resistant, borosilicate, specialty architectural
- Architectural products: Fire-resistant glass, specialty glazing panels
- Market: Commercial, institutional, and industrial - Japan and international
- Website: neg.co.jp
Product Range
- Pyroswiss / fire-resistant glass
- NEG Functional Glass
- Architectural specialty panels
Why This System
Fire-resistant glass is the primary Nippon Electric Glass product encountered in professional window cleaning. This glass is engineered to resist fire for a rated period - typically 30, 60, or 90 minutes. Its surface is standard glass from a cleaning perspective, but the framing and intumescent seals around the glass must not be disturbed. Wired fire-resistant glass - the older product with an embedded wire mesh - has a textured surface and joints at the wire-glass boundary that collect grime. These areas require particular attention in cleaning.
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 Nippon Electric Glass 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 Nippon Electric Glass 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 glass 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 Nippon Electric Glass glass 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 Nippon Electric Glass 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 glass from Nippon Electric Glass: use pH-neutral solution only on all coated surfaces. Any coating damage -- Low-E, self-cleaning, solar control -- is permanent and the unit must be replaced.
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
- In Japanese commercial buildings, fire-rated glass in stairwells and corridors is often the dirtiest glass on site - it is frequently overlooked in regular cleaning schedules. Budget extra time for these panels on first cleans
What NOT To Do
- Do not disturb intumescent seals around fire-rated glass - this is a fire safety issue, not a cleaning issue
- Do not use abrasive pads on fire-rated glass surfaces
- Do not use alkaline or acidic cleaners on fire-rated glass framings - the seals around this glass are often silicone or intumescent compounds that are sensitive to chemistry
- Do not pressure wash into fire-rated glass frame joints
Bundle Kits and Tool Recommendations
Bundle Kit
Cleaning Frequency
Clean every 4โ8 weeks depending on environment.
Frequently Asked Questions
Field Notes
โFire-rated glass is a life safety product. If a client asks about the condition of fire-rated glass panels - including seal integrity or frame condition - direct them to a qualified fire safety surveyor, not a window cleaner. Wired fire-resistant glass is increasingly replaced with clear fire-rated glass in renovation projects. The older wired product will be encountered in Japanese commercial buildings from the 1960s through 1990s.โ
Justin Orloff
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