Roller Doors
Roller doors are usually constructed of corrugated steel. They evolved from cover window and door coverings. Other materials can be used (e.g.; transparent corrugated fibreglass) where strong impact resistance is not required. Corrugations give the door strength against impacts. A typical single car garage roller door will have a preloaded spring inside the rolling mechanism. The spring reduces the effort required to open the door. Larger roller doors in commercial premises are not sprung and use a manual pulley and chain system or a geared motor to raise and lower (roll up and roll down) the door. Roller doors cannot be effectively insulated.
In the UK (and other parts of the EU), 'insulated' roller garage doors are available, using an aluminium lathe which is then foam filled, which not only adds thermal but acoustic insulation.
In terms of thermal insulation, the roller door has a typical U value of 4.9 to 5.2. A sheet steel garage door has a typical U value of 6.1 to 6.4. For 'real' thermally insulated garage doors, you would strongly consider the insulation values of a foam filled sectional garage door, which has a typical U value of 2.7 to 1.3.
Read more about this topic: Garage Door
Famous quotes containing the words roller and/or doors:
“And thus Snow White became the prince’s bride.
The wicked queen was invited to the wedding feast
and when she arrived there were
red-hot iron shoes,
in the manner of red-hot roller skates,
clamped upon her feet.”
—Anne Sexton (1928–1974)
“He took the props down used for propping open,
And set them up again for propping shut,
The widespread double doors two stories high.
The advantage-disadvantage of these doors
Was that tramp taking sanctuary there
Must leave them unlocked to betray his presence.”
—Robert Frost (1874–1963)