
Europe · Window Manufacturer
FROVIN Vinduer & Døre — Window Cleaning Guide
🇩🇰 Denmark · Last reviewed by Justin Orloff
Quick Facts
founded
1975
hq
Nykøbing Mors, Denmark
primaryMaterials
Certified pine heartwood, Wood/Aluminium
glazingPartner
In-house
marketTier
Premium - heritage and new-build residential
Brand at a Glance
- Founded: 1975
- HQ: Nykøbing Mors, Denmark
- Market position: One of Denmark's largest coupled window and door manufacturers
- Frame materials: Certified pine heartwood, Wood/Aluminium
- Key ranges: Coupled Windows (A-Window, AU-Window, AL-Window), Thermo Windows (2-pane and 3-pane), Terrace Doors, Folding Doors
- Glazing options: Single outer pane + inner low-energy thermal pane (coupled system); 2-layer and 3-layer low-energy glass; warm-edge spacer profiles; argon gas fill; acoustic glass; safety glass
- Best U-value: Uw 0.82 W/(m2K) on the AU-Window - among the best coupled window results in Europe
- Warranty: 10-year guarantee on products manufactured in Nykøbing Mors
- Parent company: Inwido Group (since 2006)
- Official care documentation: frovin.dk/teknisk-info/vedligeholdelse/
Product Range
- A-Window (Coupled)
- AU-Window (Coupled)
- AL-Window (Coupled)
- Thermo Windows (2-pane and 3-pane)
- Terrace and Folding Doors
Why This System
Two product families - coupled windows and thermo windows - each with different cleaning requirements for the glass. The coupled window system has an outer single pane and an inner low-energy thermal pane, plus an air gap between the two frames that needs periodic cleaning. Wood/aluminium thermo windows have aluminium exteriors (no repainting needed) and timber interiors (maintenance required) - different care for each surface. Coupled windows use traditional putty glazing on the outer frame - abrasive tools and harsh chemicals degrade the putty seal. The 10-year warranty requires maintaining timber surface treatment before it deteriorates - not after. South- and west-facing frames need the most attention.
Step 1 of 2: Manufacturer Recommendations
Official Care Guidance
Source: FROVIN OFFICIAL MAINTENANCE AND CLEANING DOCUMENTATION
Glass
- Clean with lukewarm water mixed with a mild detergent and a cloth, brush, or squeegee.
- Wipe edges and bottom surfaces with a dry cloth after cleaning to prevent water pooling.
- Window stickers and adhesive labels on new glass dissolve easily in water. Use white spirit or ceramic cleaner for any remaining adhesive residue.
- Initial cleaning after construction or renovation should always use abundant water to flush dust and debris.
Wood Frames
- All surfaces must be dry and free from dirt and dust before any surface treatment begins.
- Maintain painted wood surfaces with alkyd or acrylic-based products from recognised manufacturers.
- Hardwood thresholds and sills must be maintained with hardwood oil containing fungicide, designed for external use.
- South- and west-facing frames deteriorate faster - inspect and treat these first when signs of surface wear appear.
- Do not paint over the weatherstripping or moving hinge and latch components.
- Do not paint over the warranty label.
- Do not close operable frames until surface treatment has fully dried.
Wood/Aluminium Frames
- Clean aluminium exterior surfaces with a soft cloth and mild soapy water.
- The aluminium exterior does not require repainting, unlike the timber interior.
- Do not use solvents or abrasive products on the aluminium surface.
- The timber interior surface follows the same care rules as pure timber frames.
Hardware
- Oil and adjust hinges and locking points according to FROVIN's instructional guidance.
- Video guides for lubrication and adjustment of coupled windows are available on the FROVIN maintenance page.
- Contact FROVIN directly or your installer for hardware replacement and specialist adjustment.
Putty Joints (Coupled Windows)
- Putty on the outer frame of coupled windows is durable and typically only requires attention 7-10 years after installation.
- Do not use abrasive tools or solvents on putty joints.
- Damaged putty should be assessed by your installer or a qualified glazier.
Step 2 of 2: The Orloffs Protocol
The Orloffs Protocol
This is how I clean FROVIN Vinduer & Døre windows. The tools and technique below come from 25 years of daily professional work on the glass. Every step has been tested on real installations and adapted specifically for FROVIN Vinduer & Døre systems.
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 FROVIN Vinduer & Døre 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 composite 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 Frovin composite 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 Frovin 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 Frovin frames, apply the appropriate product for each surface: pH-neutral for aluminium and glass, solvent-free for uPVC, barely damp cloth for timber. Never cross-contaminate products between surfaces.
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
- Know your FROVIN product before you start - coupled or thermo, timber or wood/aluminium. The frame care differs.
- Never saturate timber frames. A damp cloth, not a wet one, is the rule on all FROVIN wood surfaces.
- Putty joints on coupled windows must not be scraped or abraded - standard squeegee technique with gentle pressure is safe.
- South- and west-facing FROVIN frames deteriorate fastest. Inspect the paint finish there every spring.
- The outer pane of a coupled window is only half of what needs cleaning. Open the frames and clean both surfaces.
What NOT To Do
- No abrasive tools, scouring pads, or steel wool on glass, frames, or putty joints.
- No solvents on timber or aluminium frame surfaces.
- Do not saturate timber frames with water during cleaning - use a damp cloth, not a wet one.
- Do not paint over weatherstripping, seal strips, or moving hinge and latch components.
- Do not paint over the warranty label.
- Do not close operable frames until any surface treatment has fully dried.
- No scraping putty joints with sharp tools or razor blades.
- No high-pressure water on windows, frames, joints, or hardware.
- Do not clean glass in direct sunlight - the soap solution dries before you can remove it.
- Do not ignore surface deterioration on south- and west-facing frames - treat before wood is exposed to weather.
Bundle Kits and Tool Recommendations
Bundle Kit
Cleaning Frequency
Glass and frames: 2x per year minimum (Inside and out. Coastal and urban environments with salt air, traffic pollution, or industrial dust: quarterly.). South- and west-facing frames: Inspect every spring (These faces deteriorate fastest - treat before wood is exposed to weather.). Timber frame surface treatment: Every 7-10 years typically (Repaint when wear is visible on lower parts of exposed faces. For most locations this applies to FROVIN putty-glazed coupled windows.). Hardwood thresholds and sills: 1x per year (Treat with hardwood oil with fungicide.). Hardware lubrication and adjustment: 1x per year (FROVIN video guides available at frovin.dk/teknisk-info/vedligeholdelse/.). Gasket and seal inspection: 1x per year (Or after a severe winter season.)
Frequently Asked Questions
Field Notes
“Glass and frames: minimum twice per year inside and out. Coastal and urban environments: quarterly cleaning recommended. South- and west-facing timber faces: inspect every spring - treat before cracks reach the wood. Putty-glazed coupled window outer frames: surface treatment typically only needs attention 7-10 years after installation. Hardware: oil and adjust once per year via FROVIN video guides.”
Justin Orloff
What's next for you?
The Skill
New to window cleaning?
Start with the core techniques before tackling premium systems.
Start Learning →The Standard
Upskill your team
Covers every system, product type, and tricky scenario.
View The Standard →Manufacturer
Partner with Orloffs
Are you FROVIN Vinduer & Døre or a similar manufacturer? Let's create official cleaning guidance together.
Get in Touch →

