(905) 761 5252
(416) 751 2511

1948 - 2015.  Serving Toronto homes for the past 67 years.

Magnetic Inserts

Inside storm windows - magnetic inserts - are used where existing windows can not be replaced, when the external look has to remain unchanged, or as seasonal protection. They also double as good sound barriers. Magnetic inserts are a low-tech solution, simple to install and maintain, and presents significant savings compared to full window replacements. 

Several systems are available in the marketplace. We found that most systems that are suitable for large openings and commercial applications are unattractive for residential use.

For residential use - we recommend the basic application, where a clear sheet of acrylic or polycarbonate (Plexiglas and Lexan are known brands) are mounted on the window frame, inside the house. This creates an additional barrier to prevent draft and employs an insulating air space, similar to a more expensive double glazed thermal glass unit.

The only visible part is a 5/8" white or brown strip (other colours can be used but are not offered by us) around the perimeter of the window. All other systems present a bulky, much wider and unsightly frame which does not blend well with most inside decor. Should you wish, you could add wood trim around the glazing, painted to match existing trim.  


  • Easy to install, remove and store
  • Easy to clean and maintain
  • Does not harm the house' exterior
  • Blends with existing window frames
  • Low cost - highly efficient solution

We offer two supply options:

For local home owners we can make and install the windows. Please call or email us with relevant information or use the contact form.

If you live elsewhere, or wish to DIY, we offer the mounting kits. All you need to do is measure, source the clear sheets locally, assemble and install. If you can manage a roll of scotch tape, you can sure do it yourself.

A basic mounting kit includes:

  • 1 coil of 100' steel strip
  • 2 coils of 50' flexible magnetic strips
  • 2 coils of 100' double sided adhesive tape
  • 1 coil of 200' trim tape - white or brown

This kit is sufficient to make about seven average sized windows.

Installation is simple:

  1.  Define whether installation is overlap (surface mount) or recessed (against blind stop) - see sketch.
  2. Overlap mount - applicable only if the casing (or lack thereof) are flat, and there are no corner boxes. If so, measure the opening and add 1 1/4" to width and height. If window sill protrudes, add only 5/8" for the height, so insert's bottom will rest on the sill.
  3. Blind stop mount - most common - where elaborate woodwork or protruding sill are on the way: install 3/4" x 3/4" clear pine stops around the inside frame. Measure the opening in three places for width and height, and deduct 1/8" of the smallest measurement. If you are very handy you can go for a smaller allowance, or follow the exact frame size, if off-square. 
  4. Material - any acrylic (Plexiglas or similar) or polycarbonate (Lexan or similar) can be used.
  5. Thickness - for most applications 1/8" will do. For larger windows (over 15 sqft), patio doors or where noise is an issue use 3/16" or 1/4".
  6. Source the clear sheets - home improvement stores carry them, but prices are high and selection is low. Check locally to find a distributor for acrylic or plastic suppliers.
  7. If possible, get the specialized supplier to cut it to size. Much depends on the neatness and precision of the cut material. An off-square cut or chipped edge does not add to the looks of your home.
  8. Apply the double sided mounting tape on the stops or on the frame, as applicable.
  9. Mount the steel strips on the tape, no need to miter.
  10. Apply the double sided mounting tape on the insert perimeter, and apply the magnetic strip on it.
  11. On the reverse side of the insert, apply the trim tape, to finish it up and conceal the magnetic tape.
  12. Install the insert in place.
  13. Exceptions - if the sill is in the way you may just rest the bottom of the insert on the sill. We can supply a foam tape to seal the sill.
  14. If you require a different colour than the offered white or brown trim try your local arts and crafts store for an adhesive tape 5/8" or wider, at the desired colour. Alternatively mount thin pre-painted wood trim around.
  15. Round top windows - the mounting kit will yield to 10" radius. If smaller than that you'll need to cut it to short pieces and trim it accordingly. 


Acrylic and polycarbonate materials scratch easily - to keep them clean and clear use a slightly damp soft cloth - no detergents. For stubborn stains use a small amount of rubbing alcohol.

Noise reduction - use 3/16" or 1/4" sheets to block noise. The inserts block the mid to high frequency, so most noises will be filtered.

Storage - protect well against scratches and store upright.

Inserts are fixed - to ventilate the room you will require to temporarily remove them.

Brown trim tape mounted on clear sheet

Steel tape mounted on wood stops (or window frame) with white trim tape

Assembled unit with brown trim tape

Inserts simulation

Installation modes

Typical overlap installation - providing no protruding window sill and casing, leave sufficient room (5/8") for mounting the steel tape. Bottom is protected with foam to ensure continuous sealing. 

Typical overlap installation - with protruding window sill: steel tape mounted on top and sides, and insert's bottom rests on sill. Optional foam tape can be installed on the insert's bottom, but is needed only in extreme cases.

Typical recessed (blind stop) installation - insert is mounted against wood stops. This looks the best, and once stops are painted they are hardly noticeable even if the insert is removed. Bottom stop can be omitted for a cleaner look.


All products are custom made

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