Les facteurs d’efficacité:
- Valeur R
c’est la valeur isolante; le plus haut – le mieux c’est
- Couche Low-e
une couche microscopique qui reflète les rayons infrarouges de l’extérieur (été) et de l’intérieur (hiver); il faut évaluer que ce type de protection diminue aussi le gain solaire. C’est le coefficient du gain solaire en chaleur = CGSC, mesuré en %. Pour régions froides 0.55 et <0.4 pour les régions chaudes
- Valeur d’étancheté de la fenêtre
Le moins – le mieux (moins que 0.3 picube/picarré de fenêtre/minute.
- Distance entre les vitres
standard: 1/2″, mieux: 3/4 »; best: 1″
les espaceurs sont souvent en aluminium; il y a des versions moins conducteurs à la chaleur: inox, mousse, plastique
- Cadres des fenêtres
bois et vinyle sont bon; meilleur: fibre de verre remplit de mousse isolante
- Efficient Windows Collaborative
- Windows & Daylighting
- Window & Door Manufacturers Association
- American Architectural Manufacturers Association
Insulating curtains that cut heat losses through windows by 50% by paradigm (instructables)
« Kume » in the language of the Mapuche people of Chile means « good. » The thermographic photograph shown above speaks for itself. It was taken early one winter morning and clearly shows that the window fitted with a Kume curtain is much cooler than the one fitted with a conventional decorative curtain – and is actually even cooler than the masonry wall.
The benefits offered by Kume curtains are as follows:
- They lower heat losses through windows by 50 to 70%, and improve comfort by eliminating cold spots and drafts in rooms. In the first test homes fitted with Kume curtains, heating fuel consumption dropped by 25%.
- They are inexpensive. The cost of the materials that are needed to make a Kume curtain typically ranges from US$ 1 to 1.5 per square foot.
- They are easy to make. Putting together a Kume curtain does not require great manual skills or much time.
Step 1: What is a Kume curtain?
- A front panel which acts as the first layer of insulation and seals the perimeter of the window opening when the curtain is closed.
- A moisture barrier which prevents indoor humidity from reaching the window and condensing on the cold glass and window frame.
3 & 4) Wooden battens which maintain the fabric stretched out and thereby ensure that the curtain fits tightly against both sides of the window opening. The battens also create air pockets which further reduce heat losses hrough the curtain.
5) A back panel which acts as the final layer of insulation and helps seal the perimeter of the window opening when the curtain is closed.
A Kume curtain can be used on any window whose frame is recessed by at least 1.5″ with respect to interior surface of a wall. This is because the curtain works best if it is able to tightly seal the complete perimeter (that is, the top, bottom and sides) of the window opening.
When raised, the curtain forms a tight roll whose diameter varies depending on the length of the curtain and the thickness of the material used. For example, a curtain that is 5 ft long and made of two layers of fleece will produce a roll with a diameter of approximately 5″.
For a window opening of width « W » and height « H“, you will need the following components:
- Front panel
Width = W + 0.75″, height = H + 0.75″
Material = Polar fleece or another thick and flexible fabric. If the Kume curtain is used as a primary curtain, the front panel can be made with a fabric that best suits the decor of the room. Wash the fabric before making the panels.
- Moisture barrier
Width = W – 0.75″, height = H
Material = Transparent polyethylene with a thickness of approx. 4 mils (0.004″). Black polyethylene sheet will make your curtain totally opaque.
- Upper batten
0.5″ x 1″ x Length = W – 0.75″
Material = Pine or hardwood
- Lower battens
0.5″ x 0.75″ x Length = W – 0.75″
Material = Pine or hardwood
Number = The spacing between the battens should not exceed 20″.
- Back panel
Width = W + 0.75″, height = H + 0.75″
Material = Ideally polar fleece or another thick and flexible fabric
- Fasteners (not shown); for the back panel we recommend using staples, while for the front panel, which is visible from the room, we recommend using thumb tacks or upholstery tacks. If you are concerned with having these fasteners rust and stain the fabric, you should use stainless steel staples and rust resistant tacks.
- The front and back panels are a bit bigger than the window opening. This is because these pannels need to completely plug the window opening when the curtain is closed.
- The fabric chosen for the front and back panels should ideally be moderately thick, tightly woven to restrict the passage of air, and flexible so that it can accommodate itself tightly against the sides and bottom of the window opening.
The making of
- Trace the position of the battens on the plastic sheet.
Make sure that:
The top edge of the upper batten is aligned with the top edge of the plastic sheet;
The bottom edge of the lower batten is aligned with the bottom edge of the plastic sheet; and
The remaining battens are evenly distributed over the height of the plastic sheet.
- Slip the battens under the plastic sheet
and use the marks traced on the plastic sheet to align them properly.
Since the length of the battens is equal to the width of the plastic sheet, the ends of the battens should also align with the sides of the plastic sheet.
- Lay the front panel over the plastic sheet.
The front panel is slightly longer and wider than the plastic sheet, so when in place:
A) The top of the front panel should be aligned with the top batten;
B) The bottom of the front panel should extend by ~0.75″ below the lower batten and base of the plastic sheet; and
C) Each side of the front panel should extend by ~3/8″ past the ends of the battens and sides of the plastic sheet.
- Use tacks to fasten the front panel and the plastic sheet to the battens.
Place a tack within 0.5″ of the ends of each batten.
Use enough thumb tacks between both ends of the battens to properly fix the fabric and plastic to the battens.
On the upper batten, the spacing between the thumb tacks should be between 4″ to 8″.
On the lower battens, the spacing between the thumb tacks can be increased to double the spacing used on the upper batten.
- Flip the curtain over.
- Place the back panel over the partially assembled curtain so that it rests directly on the battensThe back panel has the same dimension as the front panel, so when in place:
A) The top of the back panel should be aligned with the top batten;
B) The bottom of the back panel should extend by ~0.75″ below the last batten and base of the plastic sheet;
C) Each side of the back panel should extend by ~3/8″ beyond the ends of the battens and sides of the plastic sheet.
- Use staples to fasten the back panel to the battens.
Place a staple within 3/8″ of the ends of each batten. This will ensure that the material maintains its full width and touches the sides of the window opening.
Use enough staples between both ends of the battens to properly fix the fabric to the battens.
Refer to the web page www.kumeproject.com for instructions on how to mount the curtain and create the tie to hold the curtain in the rolled position. Other options for assembling the curtain are also described on this page. This web page provides the curtain assembly instructions in French, Spanish and Italian.
You can add conductive mesh to the curtain to make it a shield for EMF!