WINDOWS & BLINDS

Cut a roller blind down to size

Cut a roller blind's tube, bottom bar and fabric to a narrower width, then refit the brackets to match.

RB-01Set up a flat, protected work areaClear a table or the floor and lay down an old sheet or towel. You need a flat surface long enough to take the full roller and fabric without bending it. Have all your tools within reach before you start, so the blind isn't left half-dismantled.
1 each · Dust sheet or old towel
1 each · Junior hacksaw
1 each · Mitre box (small)
1 each · Craft knife
1 each · Metal straightedge or ruler
1 each · Tape measure
1 each · Set square
1 each · Fine sandpaper or a small file
RB-02Measure the new width and mark the cut lineMeasure the window recess or frame twice, at the top and bottom, and use the smaller figure. Check your blind's fitting instructions for the clearance it needs — most recess-fit blinds want 5-10mm spare each side so they don't bind. Wrap a strip of paper or tape around the roller tube at the mark and use it as a square guide so your pencil line goes all the way round without drifting.
RB-03Remove the plain end capEvery roller blind has one plain end cap (no chain or cord) and one control end with the mechanism. Lever the plain end cap off gently with a flat screwdriver — it's just a friction fit. Leave the control end alone; you're only shortening the plain side.
RB-04Cut the roller tube to lengthSit the tube in a mitre box so the hacksaw cuts square, and cut on your marked line. A skewed cut here throws the whole blind out, so take it slowly rather than forcing the saw. Once cut, run sandpaper or a file round the inside and outside edge to knock off the burr — a rough edge will snag the fabric or jam the end cap.
RB-05Cut the bottom bar to matchCut the aluminium bottom bar to the same finished width as the tube, using the same mitre-box-and-hacksaw method. Deburr both ends the same way. Wrap a short strip of masking tape round each cut end — it stops the sharp aluminium snagging the fabric when you slide the bar back into its pocket.
1 roll · Masking tape
RB-06Trim the fabric to widthLay the fabric flat and use the set square to mark a true right angle in from one edge, matching your new width. Place the metal straightedge exactly on this line and cut with one firm pass of the craft knife rather than sawing back and forth, which leaves a ragged edge. Most blackout and polyester blind fabrics are cut-edge and won't fray, but check yours before you commit to the cut.
RB-07Reassemble the rollerPush the plain end cap back onto the shortened tube. Feed the bottom bar back into the fabric's bottom pocket and clip its end caps on. Give the roller a spin by hand to check the fabric winds on straight and square, with no twist.
RB-08Work out what's behind the bracket fixing point before you drillA narrower blind means the brackets move inward, so you're drilling new holes. Cables and pipes can run almost anywhere near a window, including up to sockets and lights above or beside it — use a cable and pipe detector, but still treat the wall as live until you've drilled a small test hole and proved it clear, because detectors miss cables that are deep, in metal conduit, or behind metal-backed plasterboard. Find your stopcock (usually under the kitchen sink) and check it turns before you start, so you can shut the water off fast if you hit a pipe. If you're at all unsure what's behind the wall, isolate the circuit at the consumer unit before drilling.
1 each · Cable and pipe detector
RB-09Fit the right fixing for your wall or frameIf you're fixing into a wooden or uPVC window frame, use the screws supplied with the bracket kit — no plug needed, just a pilot hole in timber. Into solid brick or block, drill with a 6-7mm masonry bit to the depth of the plug, insert a wall plug, and drive in the screw. For a stud wall above the window, work out what you have first: a stud detector or magnet tracking screw heads finds the studs, a hollow sound between them confirms plasterboard, and a small pilot hole tells you the rest — timber dust means a timber stud, fine grey swarf means a metal stud. Into a timber stud, use a wood screw straight into its centre; into a metal stud, use a self-drilling metal-stud fixing or toggle made for steel, never a plastic wall plug or ordinary wood screw, as both strip straight through 0.5mm steel. If the bracket falls on plasterboard between studs rather than on the stud itself, use a toggle or hollow-wall anchor rated for the blind's weight, not a light-duty picture hook fixing. On dot-and-dab plasterboard, use a fixing long enough to pass through the plasterboard and the adhesive dabs and bite into the masonry behind — check the cavity depth with a long thin drill bit first so you buy the right length.
4 each · Wall plugs (masonry)
4 each · Wood screws (frame or timber stud fixing)
4 each · Self-drilling metal-stud fixings
4 each · Hollow-wall toggle anchors (plasterboard)
4 each · Long fixings for dot-and-dab (through to masonry)
1 each · Drill with masonry and wood bits
RB-10Rehang the blind and test itClip the roller into the refitted brackets, control end first. Pull the chain or cord to run the blind up and down its full length, checking it tracks straight and doesn't rub the reveal. If one side sits slightly lower, loosen that bracket and nudge it level before tightening fully.
1 each · Small spirit level
RB-11Clear upVacuum up aluminium filings and fabric trimmings straight away — they're sharp and easy to miss on a carpet. Fold or bin the offcuts of fabric and bottom bar. Wipe down the work surface before you put the tools away.

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