Saturday 13 March 2021

Light Well Number 1

On the top floor of Balintore Castle, there are a number of light wells which in the past brought daylight to the uppermost corridor and a bathroom. Unfortunately, the skylights at the top of the light wells were a weak-spot. When I bought the castle, every single one of these had fallen through, each leaving a large hole for rain to pour through. And pour through it did: the water damage in these areas is horrific.

One of the first things we did was to cap these holes with plywood and roofing felt. No more water ingress, but no more light.

Anyhow, we have just completed fixing up the first light well. There are around 4 altogether. A reclaimed metal conservation roof window was installed, and the well itself was fixed up and re-plastered. The roof window is one of a job lot bought on eBay after years of looking: new, they would have been 10 times the price.  

Gregor was not that impressed by the amount of light newly entering the corridor, but I am hoping that when the new plasterwork is painted white and we move towards summer things will take a turn for the better. I have yet to see the refurbished light well for myself.


You can see a circular aperture at the bottom of the light well. This used to hold a circular window with glass in 8 frosted segments. There are marks in the surviving, almost complete, wooden frame every 45 degrees. Greg reported that the well was only rough plastered originally because, given the frosted glass, there would have been no need. My current thought is to use clear glass as the replacement for maximum light transmission and indeed to show off Greg's coloratura plasterwork.

When I visited Balthayock House nearby (a possible restoration candidate - now demolished) the light wells on the top (first) floor were egg shaped with circular openings on the roof, so you got a wonderful softly moulded sculptural lighting effect just from daylight alone. The light well as a art form.

In the photo below you can see the newly installed skylight in the roof, with new slating round the edge.

Patching up the roof is a slow business, but this step forwards was particularly welcome, given the leak in the entrance hall which has suddenly got a lot worse. With every step backwards, one needs a step forwards.


  1. Feels like a white paint job should significantly increase the efficiency. I wonder if there is spatial paint you can use? The 'shinier' the white, the smoother the surface, so less light is absorbed.

  2. The ideal material for a light pipe is totally reflective, so high efficiency modern ones are mirror (chrome?) finished internally. You get paint for home cinema screens when have metallic particles in them, but I will probably try a "bright white" emulsion.

    Having looked into home cinema screens' paint in the past, I was very confused. Some people recommend grey!?!?

  3. Hmm. I guess silver-reflective is not so suiting balintore, but maybe copper could fit?

    I guess if the projectors were designed for grey screens from the beginning that might work, so you get 'blacker' blacks. But I suppose they assume white background.

    1. Hi Gorkem,

      Copper would look lovely in a light well! :-)

      Yes, grey screens in a home cinema are supposed to give blacker blacks.

      Expensive screens use directional reflection to throw back projector light into the eyes of the audience but not ambient light. My projector has a facility to correct for the colour of the wall! The best colour for home cinema walls (apart from the screen wall) is matt black, so there is not light flying around the room.

      My own view is that the law of diminishing returns applies, and I painted a home cinema screen in bright white matt paint. Works for me!

  4. OMG! This is THRILLING! I love when curious bits are resurrected! I tip my hat to you, from across the big pond.