The cord on one side broke when the blind was being opened. It looks like it frayed and finally broke. The blind now stays open. How can this be fixed?

Gilbie, November 2017

Thanks to all for posting.

I've just had the same problem with the cord wearing right through the plastic piece on one of my Duo blinds (and I can see it happening on the other one too). I called Velux today who said they are now aware of this issue due to lots of reports of the problem. Apparently this was due to blinds being manufactured with the cords too tight and so they are now manufacturing them with a bit more 'give' to prevent the plastic being worn away. They don't have a fix for it so are sending me replacement blinds that should last this time. So anyone with this problem, it's worth speaking directly with Velux.

HannahT, February 2021

Two more comments:
a) The grey plastic bits at the end of the pull down bar. I found these damaged - meaning that cord had sawed its way thru the plastic. Best to complete that work, and bust the part in half. Then with a file smooth of both the bottom still attached bit, and then the bit which broke off. Glue these back together with Super Glue.
b) When replacing the strings, make suren that you use string of about the same diameter.
start with the black tensioner end. Knot the string, and apply a lighter to make the knot smaller and permanent.
having done ONE and removed the bootom end fixing, MEASURE the strings ... and mark where the small bits are on the end.
NOW you can cut the string and complete removal.
Carry on and finish as above.

Richard T-R, January 2019

Very useful instructions, but I found that when I removed the "black clip in attachment" the blind tensioning all unravelled. I still then couldn't get those parts apart and resorted to cutting and knotting.

As to why not ask Velux, because they charge several tens of pounds to send you a part that was clearly made of the wrong material in the first place.

NMA, June 2018

I have just completed this task. first unscrew metal side runners and plastic cord retainers at the bottom and remove.Next remove the blind.there is nothing on velux website about how to do this.it clicks in on the left and just lifts out on right hand so hold blind between thumbs at front and forefingers by glass towards the left and pull hard straight down towards the floor and slightly forward.It pops out . buy new blind cord from a sewing/diy shop . replace cord each side -you will need to tie new cord onto old and pull through the bottom blind bar for each side. Mend thesmall grey plastic parts screwed onto each end of the pull down bar which the cords run through by concocting an inner sleeve out of something and gluing it in .In the Polish repair youtube videothey use a metal bushel- i used a very large bore straw which i glued in. to attach the top ends of the cords on each side remove the blackclip in attachment which sits in the sides of the blind casing by lifting it out with a screw driver and carefully open it up by opening the flat front panel then attach the new cord to the spring inside as you can see the old one is attached .At the lower endof the bottom cords open up thegrey plastic cord retainer and thread new cord through . tighten the cord though this after replacing the blind and metalside runners and then do knots inside.

Alisonjones, December 2017

Sorry if this seems a bit obvious but why not just ask Velux?

https://www.velux.co.uk/help-and-advice/spare-parts

Gjytff, November 2017