If the steel frame provides a suitable surface parallel to the glass and at least 6mm distant from the existing glass, you can attach the ClearComfort tape and membrane to the steel frame in the normal way.

If the steel frame is not positioned suitably for direct attachment of the ClearComfort tape and membrane, proceed with one or more supplementary frames.

Method 1: Attach a fixed supplementary frame

Steel frames window insulation

Fix a supplementary frame to the window reveal, using a length of square or rectangular rigid material such as timber or aluminium. 20 x 20mm is a good minimum size to work with.

Use a length of square or rectangular rigid material such as timber, steel or aluminium (eg. 30x20mm or 15x15mm) to make a second frame within the window reveal. Attach the timber/steel/aluminium to the window reveal using glue and small screws or nails. Attach the tape and membrane to the new frame as for a standard window.

Method 2: Attach a movable supplementary frame

Moveable supplementary frame

Moveable supplementary frame

For each window opening, you can fabricate a pair of identical frames (similar to empty picture frames) that will perch side-by-side against your existing window frames. You can then attach the tape and membrane to these fabricated frames and you will achieve a sealed air gap between your ClearComfort-faced ‘picture frames’ and the existing window. To open the window, simply remove the first ‘picture frame’ and stack it in front of the second ‘picture frame’, allowing access to the sliding glass window, until you want to close and seal up your window again.

Pair of identical moveable supplementary frames

Pair of identical moveable supplementary frames

Each frame is lightweight and easily made from off-the-shelf components available at hardware stores – we’ve made some using plain 40 x 20mm softwood, which can be painted or left natural, and some using aluminium flyscreen framing, which comes ready-coated in different colours as well as plain aluminium.

Single fixed or moveable frame in place

Single fixed or moveable frame in place

There are added benefits to using these frames:

  • you will block drafts that blow through ill fitting windows, and
  • will be insulating the highly heat conductive aluminium frame around the glass.