Roman Blind Wizard fold calculator for perfect Roman blinds

Roman Blind Wizard

F.A.Q. - Frequently Asked Questions

This page lists questions that've been frequently asked, and their answers. If you have any questions regarding Roman Blind Wiazard, or blind-making, please check this page to see if your question is listed, as it can often be quicker than emailing for help.

How much fabric will I need?

Roman Blind Wizard calculates the exact cut width and drop of fabric, lining and interlining required for your blind, and displays this on the Workroom Instructions. You may wish to allow additional fabric for pattern placement, pattern matching across multiple blinds, and joining or railroading fabric for wide blinds.

What hem allowance does Roman Blind Wizard give?

The side and bottom hem allowances, top turning allowance, rod pocket size etc., are all defined in your Parameters. When you first register with Roman Blind Wizard, you will be assigned a set of default parameters. You can change any or all of these parameters to suit your own preferred method of working.c

What is the Workroom Instruction Sheet?

The Workroom Instruction Sheet is produced after you click “calculate”, and contains all the instructions you need to make the Roman blind. It is displayed on the screen, from where you can print it and save it to a directory of your choice. It will also be automatically sent to the email address set up for your account.

How do I know how many credits I have left?

Just go to “Your Account” to see how many credits you have left, or check the display at the beginning of the calculator screen.

Why won’t Roman Blind Wizard Calculate?

Roman Blind Wizard tries very hard to prevent you from entering data which would not result in a valid Workroom Instruction. It does this so that you won’t waste any credits on blind specifications which are not valid. But because there are so many variables which make up the workroom instruction, any combination of these could be causing an error condition. If Roman Blind Wizard is preventing you from performing a calculation, you should carefully check the following entries:

Finished blind drop – may be too small to accommodate the folds or cascades you require

Headrail allowance – may be too large

Number of folds – may be too many to fit into your blind

Cascade increment – may be too large to fit into your blind

Additional depth on bottom fold – may be too large

What if I enter an incorrect value in the calculator screen?

Roman Blind Wizard will try to guide you to enter logical values, but if you enter an incorrect value, or if you want to change a value, you can go back to that field to enter a different value. Just remember to always TAB through all the fields again before hitting "calculate" so that the Wizard can pick up and use all the new values.

What are rod pocket spacings?

Rod pocket spacings are the distance, in centimetres or inches, between each horizontal rod in the Roman blind. Their position and spacing are important because this is what dictates how big the folds of your blind will be, and how they will be arranged when the blind is stacked up. Roman Blind Wizard produces rod pocket spacings which are measured from the stitch line of one pocket to the stitch line of the next, and so on. In this way, the measurements are correct whether you use rod pocket tape or make your pockets in the lining, and for any depth of pocket.

Why do I need a weight bar?

The Weightbar is inserted into the lower hem of the blind to ensure that the blind hangs well and lowers fully when the cords are released.

What is the Window reference?

This is just a name that you can give to the window for which you are making the blind. For example “My lounge front window” or “Mrs Jones kitchen window”. In larger workrooms the window reference can be the job number or customer order number. Your workroom instruction document will be emailed to you with this reference.

What is the Finished Blind Width?

This is the measurement, in centimetres or inches, of the finished blind from side to side.

Why will I have to join fabric widths?

If the finished width of the blind is wider than a standard width of fabric, you will have to join two or more widths of fabric together. You should always have a full width of fabric at the centre of the blind, and any partial widths at the outside. If the window is very wide, you could consider making more than one blind to dress it.

What is meant by “Railroading” fabric?

It is sometimes appropriate to “railroad” the fabric, or turn it sideways. This makes sense if the required width of the blind is wider than a width of fabric, and the required drop of a blind is less than a width of fabric. Railroading eliminates the need for joining seams, which can look unsightly. It is only possible, however, if the fabric looks right “sideways”!

What is the Finished Blind Drop?

This is the measurement, in centimetres or inches, of the finished blind from top to bottom.

What is the Headrail Allowance?

This is the amount of space occupied by the headrail system of the blind, and depends upon your chosen headrail system. The fabric cannot be folded up beyond this point, and Roman Blind Wizard allows for this when calculating the fold sizes. As a guide, for sidewinder systems allow 5 to 5.5 cm and for wooden batten and screw eyes allow 5 – 6 cm. If in doubt, measure the profile of your chosen headrail system and add to this the diameter of your cord guide rings, or depth of rod pocket tape, or distance from the eyelets to the fold of your rod pocket.

What is the additional depth on bottom fold?

You may wish the final fold of the blind to extend a little further than all the other folds, (either cascading or standard) perhaps to fully display a decorative border or trim at the bottom of the blind. Some people like to make the last fold a little longer on standard fold blinds in order to protect the other folds from sun damage. Roman Blind Wizard will take this amount into account when calculating the fold sizes. This value is zero if you do not want the bottom fold to extend.

What is the required number of fold sections?

Roman Blind Wizard will calculate the ideal number of fold sections for your blind. You must choose an odd number of fold sections, and this number should be fairly close to the ideal number calculated by the Wizard. You might want fewer fold sections (and therefore bigger folds) on a large blind or with a large fabric design. You could decide on more fold sections (and therefore smaller folds) on a narrow blind with a delicate fabric design. You can re-enter different values here to view the effect on the stacked-up depth, before hitting “calculate”.

What is the Cascade Increment?

A cascading blind is arranged so that when the blind is fully folded up, each fold finishes a little lower than the one in front, giving a cascading effect. This is also sometimes called a waterfall effect. Standard folds all finish at the same level when the blind is fully folded. Cascading blinds look attractive but take up more space even when fully folded up. If you want your blind folds to cascade then you can specify the cascade increment (the difference, in centimetres or inches, between each fold). This will normally be between 1 and 5 centimetres, depending on your design preference and the proportions of the blind. If you want standard folds then enter zero in this field. You can re-enter different values here to view the effect on the folded depth, before hitting “calculate”.

What is the total depth of this blind when fully folded up?

Roman Blind Wizard will calculate how much space this blind will take up when it is fully folded up (or stacked up). This may be important if you need to know how much of the window will be obscured by the fully open blind, or if you have to make your blind fit into a certain space. You can re-enter the headrail allowance, required number of fold sections, cascade increment and additional depth on bottom fold to view the effect on the stacked-up depth, before hitting “calculate”.

What is the number of cord drops required?

Roman Blind Wizard will calculate the exact number of cord drops for this blind width based on normal spacing criteria (approximately 35 cm between each cord). You must enter the nearest whole number – go up if this is a particularly long or heavy blind. Only go down if this is a fairly small, lightweight blind. There must be at least two cord drops.

What are the Headrail Instructions?

There are many different types of headrail available, and you may enter any details about the required headrail system, for example left or right hand operation, batten, cord lock or sidewinder, cleat, acorn, chain colour etc. You should also specify the safety device here; chain break or wall tension device, the installation height and chain length. You can leave this field blank.

What are the Special Instructions?

You may specify any additional instructions for the blind, such as borders, trims, fabric orientation and pattern placement which will be required by the workroom to complete the blind. You can leave this field blank.

What is the safety advice regarding Roman Blinds?

Window blind cords and chains can pose a risk for babies, children and vulnerable people who could injure or even strangle themselves on the hanging cords and chains. There is now a Safety Standard in force, BS EN13120, which sets out the requirements for corded window products. You must ensure that all blinds you make comply with this standard. For further information, visit: