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The Hormann Rollmatic2 has different ordering size references to nearly every other aluminium roller garage door manufactured in the UK. The Rollmatic we refer to here is the original model with an external motor drive and 110mm side guides with a spring balance system to one side.
When you order the Hormann Rollmatic2 garage door the order references are the IN-BETWEEN GUIDE WIDTH and the GUIDE HEIGHT excluding the size of the aluminium hood enclosure, which is supplied as standard to fully enclose the curtain.
The ordering reference sizes are for the actual daylight opening width and height - NOT including the side guides and roll hood enclosure.
The guides are all 110mm wide each side whatever the door size and the headroom required for the roll and hood enclosure is 290mm on doors up to 2300mm high and 335mm on all doors over 2301mm high.
Example: Installing a Rollmatic on the inside face of a structural garage opening of 2280mm wide and 2150mm high will mean an ordering size of 2280mm and 2150mm assuming of course you have sufficient headroom and sideroom for the guides and hood. The overall width will be 2500mm and the overall height will be 2440mm.
The hood enclosure for a Rollmatic2 is either 290mm or 335mm when the door is over 2300mm high (because the roll is physically bigger) so again if you have a floor to underside of lintel height of 2250 and then an internal headroom behind the lintel of 300mm you can take the total of 2250 plus the 300 which equals 2550mm and then take off the 290mm and maybe say 10mm for installation tolerance and you have left 2250mm which is the ordering height.
All Rollmatic roller doors are made to measure so there is no extra charge for this and it makes sure you get the best fit and the best drive through width and height when the door is open.