With blackout lining, do you have the woven side facing the street, or the soft felty side? Also is there a reason for having such a large hem allowance for the lining? I was planning on a 1 inch hem folded over (2" total).
We're not sure what type of blackout lining you have. With a combined
blackout interlining we would have the felty interliner facing inside
the curtain towards the fabric. With a normal blackout lining we would
make with the rubbery side of the blackout lining facing inside the
curtain towards the fabric.
You can make the hems whatever size you like. We make them the size in the tutorials because over the years we have found these hem sizes to be best for making the curtain hang well and look more professional.
My lining fabric is 45inch width and curtain fabric is 60inch width.Do I add the extra required to the lining?
Your lining panel will need to be 10cm (4 inch) narrower than your fabric panel when you come to join them together in STEP 7.
When the dfference between the fabric and lining widths is small there is no problem trimming down.
As the width of your lining is significantly less than the fabric you are faced with the choice of trimming the fabric down in STEP 7 or having an extra drop of lining in each curtain panel and then trimming the lining down.
Reducing the fabric width will reduce your fullness ratio, The more widths you have in each curtain the bigger the difference between the fabric and lining will be.
You wont go wrong by adding an extra lining drop to each curtain, then you will keep all your fabric and not risk reducing the fullness ratio too much.