Structures

Light moulding for indirect lighting

An ordinary timber trim at the wall-ceiling junction, a 7 × 18 mm aluminium profile behind it, strip in the profile. The trim is painted to match the ceiling. The cheapest indirect light there is – and it goes up in an afternoon.

Janne Halttu Janne Halttu · LedStore.fi ·

What a light moulding is

A light moulding is a timber or MDF trim from a builders’ merchant – the same one used as a ceiling cornice – fixed to the wall 40-60 mm below the ceiling or to the underside of a kitchen cabinet. Behind it, between the trim and the wall, a low aluminium profile fits, with the LED strip glued into it. The trim is the glare shield: it hides the strip from view and lets the light out only upwards to the ceiling.

It is the same idea as a plasterboard bulkhead, but the bulkhead is replaced with a single trim. No framing, no plasterboard, no filling. The only work is screwing the trim in and painting it.

Light moulding at the wall-ceiling junction - L-trim covering a 7x18 mm profile, light rising to the ceiling
A white L-trim at the wall-ceiling junction. Profile and strip behind the trim, light to the ceiling. Switched off, it looks like an ordinary cornice.

Structure and dimensions

Profile7 × 18 mm low surface profile – the slimmest that fits behind the trim
TrimTimber or MDF, 40-60 mm high, 12-18 mm thick. An L-trim or a straight trim + spacer
Distance from ceiling40-60 mm – the top of the trim. Under 30 mm makes a sharp stripe, over 80 mm and the trim becomes a bulkhead
Gap between trim and wall20-25 mm – 18 mm profile + the strip’s cable
Space from the wall20-30 mm depending on trim thickness
StripCOB 7.2-14.4 W/m, max 8 mm wide – 10 mm does not fit in a 7 mm profile

The trim height is the glare shield

The strip is right behind the trim, so the lip can be low – 20-25 mm above the top of the strip is enough from seated height. A 40-60 mm trim therefore gives a generous margin. The light is cut at the edge of the trim and leans towards the wall – that is the nature of this structure, not a fault.

LED profile behind a timber light moulding
LED profile behind a timber light moulding

Installation step by step

  1. Mark the top edge of the trim with a laser 50 mm from the wall along the whole wall.
  2. Nail the trim to the ceiling along the marked line. The easiest is a finish nailer, every 50 cm. Alternatively, first glue small L-brackets to the trim and screw through them into the ceiling behind the trim.
  3. Screw the LED profile brackets to the ceiling behind the trim and press the trim into place against the ceiling.
  4. Glue the strip into the profile and run the cable from the end of the profile to the corner or behind a cabinet to the driver.
  5. Fit the LED profile cover staggered, starting with a long cover from the cut end of the profile, so that the profile and cover joints do not overlap.
  6. Connect and test: sit where the sofa is and look at the light =)
  7. Acrylic filler or wood filler in the trim joints and any screw or nail marks.
  8. Paint the trim to match the ceiling – matt. Switched off, it disappears into a cornice.

In practice: bedroom 3 × 4 m, three walls

The wall on the bed side is left out (the strip would be visible lying down). Three walls 3 + 4 + 3 = 10 m. 7 × 18 mm profile 10 m about €200, COB strip 7.2 W/m 10 m €150, MDF trim 45 mm 10 m €25, 100 W driver €70, paint. Total under €500. Work: one afternoon, no electrician if the driver is a plug-in on top of a chest of drawers.

Light moulding vs. plasterboard bulkhead vs. surface profile

Light mouldingSurface profilePlasterboard bulkhead
Space required20-30 mm15-30 mm50-150 mm
Visible when offAs a corniceAs an aluminium trimNot visible
WorkAn afternoon, no professionalAn afternoon3-4 days, carpenter + painter
Materials / m€25-35€35-50€25-30 + labour €100-200
CornersTrim mitred, strip breaksProfile 45°, corner connectorSeamless
SuitsFinished room, on a budgetFinished room, modern lookRenovation, best result

Retrofit – all methods → · Wall-ceiling junction → · Glare shield →

Frequently asked questions

What is a light moulding?

An ordinary timber or MDF trim at the wall-ceiling junction that hides a 7 × 18 mm aluminium profile and LED strip behind it. The trim is the glare shield and is painted to match the ceiling. The cheapest indirect light for a finished room.

Light moulding or plasterboard bulkhead?

A light moulding goes up in an afternoon and takes 20-30 mm. A bulkhead needs 3-4 days of building work but is seamless. Light moulding for a finished room, bulkhead for a renovation.

Can a light moulding be painted?

It should be painted to match the ceiling with matt paint – switched off, it disappears into a cornice. Timber and MDF paint normally. If the trim is aluminium, use a primer first.

How is a light moulding fixed?

With screws or nails into the wall every 40 cm, countersunk and filled. An L-trim straight over the profile, a straight trim on 20 mm spacers. Glue alone will not hold for years.

How are light moulding corners done?

The trim is mitred at 45° like a cornice. The strip is cut before the corner and continued with a corner connector – a 3-5 cm dark spot remains in the corner, which does not show on the ceiling.

Which strip behind a light moulding?

COB 7.2-14.4 W/m, max 8 mm wide – a 10 mm strip does not fit in a 7 mm profile. COB, because the profile is shallow and SMD would show dots.

Profiles for this structure

Moulding and shelf profiles

A light moulding can also be bought as a ready profile. These models are fitted to a shelf or moulding, or suspended from the ceiling, with no joinery.

Hides the track 1 / 5
At the ceiling edge, in front of the curtain track

Profile-curtain-DECO-W-2m

Screwed to the ceiling in front of the curtain track: the profile hides the track and directs the light down along the curtains. Takes a strip up to 20 mm, so a powerful 14-30 W/m strip fits. One product solves both hiding the track and the lighting.
Dimensions 55 mm high · 29 mm wide
Max strip 20 mm
Installation Screwed to the ceiling
60 € LedStore →
Skirting 1 / 4
Skirting profile

Profile-floor-molding-3m

Works as a skirting board and a light moulding at the same time: screwed to the wall and the cover pressed into place. Light down onto the floor – evening mood in the living room, a night light in the corridor or the lower line of a staircase. Powder-coated surface withstands wear, IP44.
Dimensions 3000×80×15 mm
Max strip 12 mm
Installation Surface, IP44
71 € LedStore →
Max shelf 17.5 mm 1 / 5
Shelf edge

profile-shelf-EDGE-W-3m

Slides over the edge of the shelf: mounting recess 17.5 mm high and 10.4 mm deep, so the shelf may be at most 17.5 mm thick. Fixed with double-sided tape or adhesive. The 30.7 mm front strip hides the strip and the light is directed under the shelf without glare.
Dimensions 30.7 × 11.6 mm · 3 m
Max strip 8 mm
Installation Tape or adhesive
60 € LedStore →
Max 7.2 W/m 1 / 5
Moulding and step profile

Profile-indirect-molding-stairs-3m

A slim T-shaped profile for mouldings, stair steps and shelves. Only 14 mm high, screwed from above or taped. The light is directed indirectly, so the walkway is lit without glare. Also suitable for outdoor use. Note: on steps max 7.2 W/m – 3.6 W/m CCT is enough.
Dimensions 40 × 14 mm · 3 m
Max strip 9.5 mm
Installation Tape or screw
99 € LedStore →
Driver inside 1 / 5
Suspended, two-directional

profile-suspended-2-51-76-W-3m

Suspended from the ceiling on adjustable wires (0-1000 mm). Three strips: two side by side downward as task light and one upward as indirect light. The deep profile hides the strip’s dots, so HELMI 14.4 or 17 W/m is enough. The body can hold a narrow TRIAC driver of up to 100 W – a luminaire with no external parts.
Dimensions 51 × 76 mm · 3 m
Max strip 28 mm
Installation Wire 0-1000 mm
175 € LedStore →

Prices include Finnish VAT of 25.5 % and are current LedStore.fi prices. Profiles include an opal cover and end caps; the LED strip is ordered separately.

Completed projects

Light moulding toteutettuna

Puulistan taakse asennettu matala profiili – valolistan neljä toteutusta.

1 / 4

Photos: completed LedStore.fi projects.

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