slats #2

Slatted ceilings progressing in the inner ‘box’!

For the last few weekends I have been working on the slatted ceilings in the inner box that cover the services but are demountable and so provide permanent access. As described in another post they are softwood timber finished with a grey Osmo woodstain and matt Osmo topcoat.

After measuring and cutting to length I laid out the slats in order and stained them in batches. They require 2 coats and then a top coat, so I numbered them on the back so that they wouldn’t get mixed up. In the second photo you can see a double assembly which is ready to receive an LED light - more on this later. In the third photo you can see the shorter pieces which are required to make up the areas around the smoke detectors and sprinkler heads, as described in the earlier post.

These photos show such a central ‘block’ from the ‘back’ (facing up towards the ceiling), and the ‘front’ which will face down towards the room.

This is the assembly process: a strip of EDPM rubber around the perimeter edges that will be seen from below or diagonally, and some plastic spacers to keep the pieces separated and avoid over-compression of the rubber strip once screwed together. I pre-drilled the upper piece in each case to allow the thread of the screw to pass through easily so that it really grips the piece below, and makes a strong connection between the slats.

This is the view from above. Once assembled I cored a minimal hole to receive the cable for the smoke detector. We are using Nest multi-functional alarms throughout to cover smoke and heat detection, so they have a short section of removeable cable that is hard wired to the mains electricity cable at one end and clips into the detector head at the other. They also have a screw on base, shown below, and the detector head fits on to this with a twisting motion, so it is important to work out the orientation before the slats are fitted to the ceiling to ensure that the head is aligned orthogonally!

The cable from the rear… The cable with it’s connectors fitted to allow easy connection to the mains cable later… The final head twisted into position on the front.

The other aspect of the slatted ceiling is lighting. We are integrating LED strip lights into the slats instead of hanging pendants between. We decided to do this to (a) keep the lighting flush, and (b) because the gaps between the slats are quite minimal.

These photos show the process: firstly the channel is measured to fit; then the LED strip is measured to fit that, leaving enough tolerance for the cut position and the cable connection at the end. We are using black channel so that it ‘disappears’ visually and reads like a gap between slats when the lights are off. The third photo shows the spacer blocks of wood I made at the fixing points of the double slat assembly. These keep the two slats exactly the right distance apart for the LED channel.

The LED strip has multiple cut points. Once it is cut to length I temporarily taped the end in position and then moved along the fitting removing the self-adhesive backing strip and adhering the strip to the inside of the channel. There is then a transulcent plastic cover that slides into the channel and covers the LED' bulbs making the light diffuse.

Here are some photos of me installing the lights and other ‘fixed’ components, such as smoke detector positions, in place before any individual slats are fitted. You can see the black cable tray in position and the orange sprinkler pipe above. On the second photo you can also see a corner of plumbing pipe still waiting to be insulated!

In these photos you can see the cable tray connections, with a slotted screw and washer to one side and a threaded rod to the other, with all cables tucked between the supporting rods. The third photo shows a tricky connection where the slats are directly below the cable tray and the ducts are sufficiently low that we have no space for our supporting batten each side! The fourth photo shows another case where the duct was smaller, but still ate into the supporting batten zone. In the last photo you can also see the masking tape with markings as I worked out the spacing of the individual slats between the fixed position items.

These two photos show the slat in question above with it’s connection being made ready for hanging from the cable tray. I pre-drilled the slat and fitted some threaded rod to hang it from, then used a double nut to adjust it to the right height, with a final nut and washer installed from above, from within the inside of the cable tray. This means the slats can still be removed later if needs be.

The final result starting to take shape along the hallway.