Using Sun Tunnel Skylights to Bring More Light into a Garden Space?

[delightfulbags]

Hi everyone!

I’m planning a garden room/greenhouse‑adjacent space that doesn’t get much natural light and I’ve been looking into sun tunnel skylights (tubular daylighting devices) as a way to brighten it up. Has anyone here used them in a garden setup, potting room, or other plant space?

I’m curious if the light they provide is strong enough for plants or just for general visibility.

Do they help reduce artificial lighting needs?

Any tips on placement, installation challenges, or real‑world results would be great!

 

[oneeye]

I don't recommend them because of the problems that come later in time. First of all you have to damage the roof and displace the roof's integrity just to install one. If not done with absolute persision you can run into big problems later. They can break much easyier than the roof during big storms. Also, I don't think they are worth the trouble because the light bends and is very low light compaired to older skylights.

Improper flashing and sealing during installation are primary causes of leaks, especially on steeper or complex roofs. Condensation can form inside the tube over time and sweat causes water damage and mold and roof leaks more common with tubes.

 

[Sheal]

Sorry not a garden set up but I have one in my home and it gives a lot of light even though it has an opaque 'lens' indoors. It has the strength of a bright bathroom ceiling light. My home is 11 years old and it was built in at the time of construction and so far no issues with it.

 

[scarecrow garden in China]

For rooms lacking sufficient natural light, you can consider a "sunlight guiding system," although the initial cost is quite high. I've researched it, and it mainly consists of three parts: a collection unit (placed outdoors) that tracks the sun and collects sunlight; a light-guiding fiber optic cable that transmits the sunlight to the desired indoor space; and a light fixture (installed indoors). This system can naturally guide sunlight to areas with insufficient light, and there are no electricity or other ongoing costs. The only drawback is the high initial investment.

 

[Martin Mikulcik]

Just installed 3 last week, solatube, i mildly don't recommend, Sheal has the best case scenario. I don't think they're any more prone to leaking than a vent, don't know about condensation, but they're underwhelming overall.

 

[Sheal]

For rooms lacking sufficient natural light, you can consider a "sunlight guiding system," although the initial cost is quite high. I've researched it, and it mainly consists of three parts: a collection unit (placed outdoors) that tracks the sun and collects sunlight; a light-guiding fiber optic cable that transmits the sunlight to the desired indoor space; and a light fixture (installed indoors). This system can naturally guide sunlight to areas with insufficient light, and there are no electricity or other ongoing costs. The only drawback is the high initial investment.

It would be a waste of money where I live @scarecrow garden in China, we don't get enough sun here. I wouldn't spend out for solar panels either.

 

[gittyup]

If practical, just use fixed skylights. They'll give you more light, and probably cost less to install, especially in a new build. Fixed skylights don't have the leaking problems as much as the ones that open. Of course, the steeper the roof pitch the more reliable the skylights will be. We had 4 large Velux fixed skylights with electric shades for 20 years and never had an issue with them. Shades are are only needed if you expect to have a big sun load that requires metering.

 

[PGB1]

Some very many years ago, I installed two skylights in a room with a cathedral ceiling. Plants upon which the sun shined through didn't grow any better than those not in the view of the sky lights. Hmmm...

An "Oh Yeah!" moment told me the answer: The glass is laminated safety glass and has plastic in between layers of glass. The plastic blocks UV. (The same reason that some automatic darkening eye glasses won't darken behind a windshield, which has the same plastic layer.) Positive Side? The color of the flooring doesn't fade.

However, under the garden windows (without the laminated glass) plants grow like gangbusters!

So be sure to choose roof windows without plastic laminations. (I wonder if plastic greenhouse windows let in enough UV and what kind of plastic that is.)

Paul
PS: The windows are perhaps 25 or 30 years old and we've not had any leaks. Condensation isn't any more a problem than it is on our regular windows when "someone" turns the humidifier up too high.

PPS: When it snows, the glass is blocked. You may have to clear the snow to let light to the plants.

 

[gittyup]

Use glass that does not filter the light (no Low-E glass). Just know that the room will heat up. So you'll need to have a ventilation system of some sort .

 

[PGB1]

Use glass that does not filter the light (no Low-E glass). Just know that the room will heat up. So you'll need to have a ventilation system of some sort .

Ours open. It's amazing how much heat from the room flows out of the opening, especially if a window in a wall is opened.

For extra hot & sunny days, I took a sheet of radiant barrier and wrapped the ends around two spring tension curtain rods. They get put in the windows to reflect the sun's radiant energy back out. I also crack the windows open a bit on the hottest of days.

Paul
PS: Written on a (-) 2 degrees-F day. Come On In Sun!

 

[gittyup]

Ours open. It's amazing how much heat from the room flows out of the opening, especially if a window in a wall is opened.

For extra hot & sunny days, I took a sheet of radiant barrier and wrapped the ends around two spring tension curtain rods. They get put in the windows to reflect the sun's radiant energy back out. I also crack the windows open a bit on the hottest of days.

Paul
PS: Written on a (-) 2 degrees-F day. Come On In Sun!

I personally do not recommend skylights that open because of the high rate of leaking associated with that type of skylight. It's best to have a separate window, transom or jalousie, preferably with a fan to force hot air out.

 

[PGB1]

I suppose success is all in the brand.

Our Velux brand are more than 35 years old & no leaks yet. (Maybe closer to 40 years)

Downside to Velux is that the crank handles broke a couple of months out of warranty and the company already had obsoleted them. (Made new ones in the shop. Now that 3D printers have been invented, I'd imagine that making some would be simple.)

Both of our American Craftsman garden windows (which also open) had a broken seal between panes problem, thus fogging. The company sent new windows of an improved design. No problems since.

Our PlyGem awning windows have been a disaster from the beginning. Leaks, popped glass seals, mechanisms falling apart, trim falling off, freezing closed due to condensation gathering in the concealed mechanism & more.

Warranty service is awful- Each time it was a minimum of 6 months of constant pestering to get replacements sent.