Solatube Frequently Asked Questions

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What is seasonal consistency and why is it important?

The ability of a tubular daylighting device to capture low-angled winter light may differ significantly from its ability to capture high-angled summer light. The ratio of summer to winter light output can be an indicator of the product’s effectiveness in delivering (or not delivering) consistent light throughout the course of a year. Solatube® Daylighting Systems will produce uniform levels of output regardless of season (or climatic conditions), resulting in steady and reliable interior illumination despite variations in exterior conditions or seasonal changes in the daylighting resource.


Are Solatube Daylighting Systems maintenance-free?

The Solatube® Daylighting System features passive daylighting technology that does not rely on moving parts, making it virtually maintenance-free. All assemblies (dome, flashing, tubing, diffuser) have seals to prevent bug and dirt infiltration. In addition, the dome and flashing are designed to eliminate debris build-up. Unlike traditional skylights, that need periodic cleaning and inspection, the Solatube Daylighting System does not require ongoing maintenance.


Are the domes strong?

The domes used with most Solatube® Daylighting Systems are injection-molded with impact modified acrylic. The high quality and durability of the material combined with the molding process produces a dome that creates a benchmark for the industry. For markets in High Velocity Hurricane Zones, the optional Shock Inner Dome is available to meet building codes. This material is required to pass stringent missile impact tests for hurricane threat areas. In the Solatube SolaMaster® Series, we also offer a military-grade dome for applications that require anti-terrorism blast testing.

The Solatube SkyVault® Series dome, intended for commercial use, is made of high-impact, vacuum-formed polycarbonate that is 43 times stronger than acrylic. A different material is used with this model due to the dome’s massive 29 in. (74 cm) size. An acrylic dome with that diameter would be too flexible and not strong enough to withstand high impact conditions. This model is also available with a dual-glaze dome assembly that includes an outer and an inner dome for added durability.


Can a Solatube Daylighting System be installed horizontally?

Yes. Optional Spectralight® Infinity 0-90 Degree Tubing creates up to 90 degree angles and allows the light to run horizontally. You can even achieve multiple 90 degree turns in the same tube run.

CAD drawings are available on the Technical Resources page of our website.


Are there any issues with leaks?

Solatube® Daylighting Systems have a variety of seamless, self-mounted flashing options, curb-mounted caps and roof accessories that, when combined with the dome and seals, provide a virtually leakproof system.

For more information, see the “Flashing” menu in the Product Selection Guides for our specific daylighting product


Can a Solatube Daylighting System be installed through a wall?

The Solatube® International, Inc. roof components have been designed for installation at the roof level, not on a vertical wall. By installing the roof components on a vertical wall, the product warranty would be voided. However, installations of this type have been done successfully. We recommend a warranty from the installer to cover this type of application.

An application where the roof components are mounted on the roof and the tubing makes a 90 degree turn to allow the diffuser or Decorative Fixture to be mounted on an interior wall are within the bounds of the warranty.

For more information, please contact your local Solatube daylighting expert.


Can a Solatube Daylighting System be used for multi-story applications?

Yes. As long as there is space for the tube run, a Solatube® Daylighting System can run from the roof to lower floors. See product pages for maximum recommended tube lengths. In addition, a chase or enclosure is usually built around the tubing for added protection.


Can a Solatube Daylighting System store light for use at night?

No, the Solatube® Daylighting System only transfers the available sunlight that enters through the dome during the day. However, the optional Solatube Light Add-On Kit may be installed so that the Solatube Daylighting System can be used as a standard lighting fixture at night that operates using a standard wall switch. Available only with the Solatube Daylighting Systems 160 DS or 290 DS.

The Solatube Smart LED™ System is an alternate option that delivers day and night lighting without the need for a Light Add-On Kit. It uses SunSense™ Technology that combines daylighting with LED technology to seamlessly transition from daylight to night lighting or to supplement at times when sunlight is insufficient. The optional Occupancy Sensor makes the system even more energy efficient by preventing the LEDs from turning on unless an underlit area is occupied.


Can I install Solatube International, Inc. products myself?

For residential applications

While Solatube® Daylighting Systems and Solar Star® Attic Fans are engineered for easy installation, you’ll get the best results when you hire a professional who has been factory-trained and certified to install our products. When arranging installation, we recommend you hire a Solatube Premier Dealer who is licensed, bonded and factory-trained on Solatube products to ensure a proper install and protection from unforeseen circumstances.

A general contractor, roofer or local building material supplier may also be able to assist you.

As a homeowner, we recommend installing it yourself only if you have the proper tools and training, and are comfortable making a roof penetration.

For commercial applications

For commercial applications, we recommend a Solatube International Commercial Distributor who has been factory-trained on all Solatube products. They can offer design assistance and/or installation services / training. Coordination with a general contractor or roofer may be required depending on the scope of the project.


Can I split the tubing and light two rooms from only one dome?

No. To transfer the most light possible to your interior, Solatube®, Inc. International uses a 1-to-1 product design that matches the dome to the diffuser. There is no “Y” tubing adapter available for Solatube Daylighting Systems that connects two diffusers to one dome.


Can Solatube Daylighting Systems be installed in a shower?

Yes, but there are potential issues with this type of application. Due to the excess moisture present in the shower environment, condensation may occur. Since the accumulation of moisture is a natural occurrence, it is not covered under the manufacturer’s warranty. To minimize condensation, proper ventilation is crucial. In addition, using the Solatube® Natural Effect Lens is recommended to reduce the air exchange between the shower and the inside of the tubing.

For more information about our warranty, visit the Product Registration page in the Support section of our website.


Can Solatube Daylighting Systems be installed on a metal roof?

Yes. We offer three different options, depending on the type of roof and Solatube® product you’re using.

Option one is a Metal Roof Kit that can be used in conjunction with our self-flashing systems on most standing seam metal roofs with seams that are less than 4 1/2 in. (114 mm) high. This is the most commonly used application for our Solatube Daylighting System 290 DS as well as our Solatube SolaMaster® Series 330 DS and 750 DS. This is the only option for our Solatube SkyVault® product for metal roofs of all types.

Option two is the curb cap used on a curb (made by others) where the curb is custom-fabricated to fit the metal roof profile. This is the most commonly used application for our 290 DS, 330 DS, 750 DS models, and the only option for our Solatube SkyVault® Series product for metal roofs of all types.

Option three is the Solatube Metal Roof Flashing, which is available exclusively for our Solatube SolaMaster Series. Featuring an innovative triple-seal Dry-Lock technique, it can be adapted to fit virtually any standing seam roof profile.

See our Production Selection Guide and Technical Resources pages for more details.

It’s always recommended that you contact your local Solatube daylighting expert for specific application details.


Can Solatube Daylighting Systems tolerate very heavy rain?

Yes, all Solatube® Daylighting Systems are designed with features that prevent water from entering the system. The round shape of the domes themselves prevent water from collecting on the surface.

In addition, the circular and seamless, one-piece design of the self-flashing systems allows rain runoff to naturally flow past the daylighting system. As a result, the flashing has no weak points that could separate and allow water to enter. However, an optional turret extension may be added to raise the dome above the roof deck where required.

For curb-mounted applications, the height of the curb would raise the dome sufficiently to avoid any rain runoff. The curb itself (made by others) would typically incorporate a water diverter (cricket) for sloped roof applications.


Can the Solatube Daylighting System run down the outside of a structure and turn 90 degrees through a wall into the interior?

The tubing of a Solatube® Daylighting System is not designed for exposed exterior applications. As long as the exterior tube runs are encased for added protection, however, this type of application is possible. To accommodate multiple 90-degree turns, angle adapters are available that provide maximum flexibility while resulting in minimal light loss. Also, keep in mind that the roof components must be supported if they reside on the side of the structure rather than the roof.

Note: this type of application may void the warranty. Consult your Solatube daylighting expert for more information.


How can condensation be managed?

Condensation in homes or buildings is mainly a winter problem. It occurs most frequently in areas where warm, moist air is generated and allowed to penetrate to colder parts of the building. A number of activities can produce moisture, including cooking, bathing, washing dishes and/or clothes, heating, and humidifying. Condensation may be more severe in buildings with inadequate ventilation.

In Solatube® Daylighting Systems, condensation can occur when warm, moist air enters the tubing or the space between the flashing or curb cavity. If this happens, it’s likely that moisture is also present around or on other building elements, such as windows, doors and skylights.

While condensation cannot be eliminated entirely, Solatube International has made design changes to its daylighting systems over the years to reduce its occurrence. The current systems are designed to allow warm, moist air to escape at the dome level while preventing air infiltration in the tube run and at the diffuser level. Modifying your system with a Dome Upgrade Kit, Flashing / Curb Insulator, Effect Lenses, Severe Climate Glazing, or Curb Cap Insulation Kit may also help, but your local Solatube International, Inc. expert is best-suited to determine if these improvements or other changes will help minimize condensation in your Solatube Daylighting System.

Due to the numerous contributing factors to condensation in a home or building, Solatube International, like most window and skylight companies, does not cover it under the manufacturer’s warranty. As such, please be aware that there may be a charge for the service call and/or additional parts needed to upgrade your system.


How do I remove my Solatube Daylighting System diffuser or Decorative Fixture?

For Residential applications

Your Solatube® diffuser or Decorative Fixture is quite easy to remove and clean. Please note that Solatube Daylighting Systems manufactured before 2000 have twist-lock diffusers for the 10 in. (250 mm) and 14 in. (350 mm) models. For these older units, the diffuser twists off counterclockwise when looking up at the diffuser. 
If you have a unit that was manufactured between 2000 – 2007, simply pry down one edge of the white trim ring using something flat like a butter knife. Continue to work your way around the ring until you have a 1/4 in. (7mm) or so gap all the way around. Then simply grab onto the edges and pull straight down. The diffuser lens can be cleaned with soap and water. To re-install the diffuser, position the four zip ties into the four holes on the ceiling ring and push up until the diffuser is flush with the ceiling.

If you have a unit that was manufactured between 2007 – 2010, simply pull the diffuser straight down.

If you have a diffuser or Decorative Fixture that was purchased after September 2010, you’ll need to twist off the diffuser counterclockwise.

For the QuadraFrost™ and AuroraGlo™ Decorative Fixtures, simply rotate the screws located on the sides of the fixture counterclockwise to release. Make sure to support the underside of the fixture when releasing it from the ceiling.

For Commercial applications

For Solatube BrightenUp® Series or Solatube Smart LED™ Systems, see instructions above for removing a diffuser or Decorative Fixture.

For the SolaMaster® 330 DS-C and 750 DS-C, remove the diffuser by releasing the tabs on the diffuser frame from the transition box. For the Solatube SolaMaster Series 330 DS-O and 750 DS-O, find the four raised lines on the plastic trim of the diffuser. This indicates where the tube notches are that hold the diffuser in place. Depress above the raised lines to disengage the diffuser from the notches.

For the Solatube SkyVault® Series, first remove the tube belt above the diffuser. Next, lift and untwist the diffuser to unlock it from the Tab-Lock Connection System.

Important note: When removing any diffuser, keep all seals in place to insure proper reassembly. See installation instructions for reattaching diffuser in the Technical Resources section of our website.


How does a Solatube Daylighting System compare to a traditional skylight?

Traditional skylights have their place as do tubular daylighting devices (TDDs). There are a few key benefits of the Solatube® Daylighting System, however, that allow our TDDs to perform better than skylights. Some of these include:

  • flexible location options
  • low-cost installation
  • optimal thermal performance
  • optical enhancement devices
  • no structural changes
  • consistent and visually comfortable daylighting
  • easy customization with modular components

For more details, read “The Skylight Alternative” article in the residential Info Center of our website.


How does a Solatube Daylighting System work?

From sunup to sundown, the Solatube® Daylighting System captures the sun’s rays using an optical dome mounted on the roof. The light is then transferred downward through proprietary Spectralight® Infinity, the world’s most reflective tubing. Designed for minimal light loss, it also easily maneuvers around obstructions with no structural changes required. When the light reaches the interior, it is delivered evenly throughout the space through specially designed Solatube diffusers and/or Decorative Fixtures.

How does Solatube International, Inc. use optical technologies in its domes to capture and control the sunlight?

At the roof level, there are two main optical technologies used in the domes of Solatube® Daylighting Systems: LightTracker™ and Raybender® 3000. The LightTracker Reflector captures low-angle sunlight, specifically in early morning, late day and winter, that would otherwise pass through the dome, and redirects it into the tube. In this way, the system collects the maximum amount of light possible throughout the day and year. This, in turn, yields greater light output in the interior space.

Raybender 3000 Technology is a patented daylight-capturing Fresnel lens integrated into the dome that provides consistent daylighting throughout the day. It accomplishes this by redirecting low-angle sunlight to increase early morning, late afternoon and winter performance. It also rejects overpowering midday sunlight, especially in summer, to reduce glare and heat offering a more consistent daylighting experience.

For additional details on specific technologies used in our product lines, visit the Technology section of our web site.


How does the tube attach to the ceiling?

For residential applications

For Solatube® Daylighting Systems, the bottom tube comes pre-assembled from the factory with integrated fastening clamps in the ceiling ring. For Solatube Smart LED™ Systems, the fastening clamps are attached to the High-Performance Amplifier rather than the bottom tube. Once inserted into the ceiling opening, the bottom tubing telescopes into the top tubing. The integrated fastening clamps secure the ceiling ring into the ceiling.

If using AuroraGlo™ or QuadraFrost™ Decorative Fixtures, please see Solatube Decorative Fixtures installation instructions appendix for additional details.

For commercial applications

If using the Solatube Brighten Up® Series or Smart LED System, refer to the above information for either suspended or hard ceiling applications.

For the Solatube SolaMaster® Series, we offer a transition box in our Solatube SolaMaster Series 750 DS-C and 330 DS-C models. This allows for integration into a suspended, acoustical ceiling grid, replacing a typical 2 ft by 2 ft ceiling tile. The transition box also offers a trim lip so that it can be used in a hard ceiling.

For Solatube SolaMaster Series 750 DS-O and 330 DS-O models, our round open ceiling diffuser can be used in a hard or suspended ceiling. You may want to add an additional trim ring for cosmetics.

The Solatube SkyVault® Series is not recommended for drop ceiling applications.


How durable is the Solatube Daylighting System?

Solatube® products are manufactured using the highest quality materials, so they are extremely durable and designed to last. All Solatube Daylighting System components (excluding electrical components) are covered by 10-year warranty. A multitude of Solatube products have been in operation for more than 20 years and continue to perform exceptionally.

We have specific product configurations that can meet High Velocity Hurricane Zone requirements as well as OSHA fall protection standards and military anti-terrorism blast requirements. Click here to view our code compliance report for specific test standards


How long does it take to install a Solatube Daylighting System?

For residential applications

Solatube® Daylighting Systems feature factory-assembled parts for faster, easier, more professional-looking installations. With this in mind, installing a Solatube Daylighting System on a shingle asphalt roof usually takes two hours or less. Other roof types (e.g., slate, tile, metal, concrete) may take slightly longer due to the roof material.

For commercial applications

Installation times can vary greatly depending on job site conditions, roof type, roof mount options, model and product configuration, and so on. Contact your Solatube daylighting expert for more information.


How much air can the Solatube Ventilation Add-on Kit move?

A typical bathroom fan will move about 50 cubic feet of air per minute (CFM). The proprietary fan / motor in the Solatube® Ventilation Add-on Kit is rated at 110 CFM (3 cubic meters per minute), which means it is more than twice as effective at clearing air than a standard fan.


How much attic space is needed to install a Solatube Ventilation Add-On Kit?

A minimum of 12 1/2 in. (318 mm) between ceiling joists and a minimum of 12 in. (304 mm) of vertical clearance above the ceiling is required in order to use the Ventilation Add-On Kit. It is also important to note that service access is required to the fan motor assembly junction box.

How much does a Solatube Daylighting System cost?

Solatube® Daylighting Systems vary in price based on a number of factors, including:

  • System model
  • Roof type and pitch
  • Tube length and angles
  • Optional accessories and add-ons, such as Daylight Dimmers and tubing extensions
  • Regional economy and location

Installation costs are listed separately, and vary based on region as well as the complexity and difficulty of the install. Your local Solatube daylighting expert can provide you with a free assessment and estimate. Call 1-888-SOLATUBE or request a quote here.


How quiet is the Solatube Ventilation Add-On Kit and does it have a sones rating?

The Solatube® Ventilation Add-On Kit features an in-line fan motor assembly that is remotely mounted in the attic or plenum rather than on the ceiling of the room to be vented. This significantly reduces the noise level in the room below.

At this time, there are no sones (sound) level test standards available for this product due to the number of variables involved with its installation, such as:

  • Type of duct
  • Length of duct
  • In-line fan motor assembly distance from intake source

However, it is generally accepted that remote-mounted venting is usually quieter than in-room venting.


Is there a Ventilation Kit available?

The Solatube® Daylighting System 160 DS is available with an attractive optional Solatube Ventilation Add-On Kit. When the Solatube 160 DS is combined with a Ventilation Add-On Kit and a Solatube Light Add-On Kit, it becomes an attractive 3-in-1 ceiling fixture.

  • Quiet, remote in-line fan motor with opposing rotation to overcome pressure and increase speed and volume of airflow, even under extended duct runs
  • Fan motor moves up to 110 cubic feet (3 cubic meters) per minute
  • Optional Roof Vent Cap: Self-flashing design for easy installation. Gravity damper prevents back flow. Low profile in black color blends with roof.

Recommended for residential use only.


Is there a way to turn off or “block out” a Solatube Daylighting System?

Yes, the Solatube® Daylight Dimmer controls the amount of natural light entering a room. Utilizing a patented butterfly baffle design and a convenient wall-mounted switch, it allows the user to adjust light levels simply and easily anywhere between 100% and 2% daylight. Designed for both residential and commercial applications, it’s perfect for bedrooms, family rooms, offices, classrooms and conference rooms. The Daylight Dimmer is available for the Solatube Daylighting System 160 DS and 290 DS, the Solatube Smart LED™ System, and the Solatube SolaMaster® 330 DS and 750 DS. The Daylight Dimmer can also be integrated with an overall lighting control system. For more details, click here for the Daylight Dimmer Integration Guide.


Is there an electric light for nighttime use?

You can get day and night lighting in one unit with the revolutionary Solatube® Smart LED™ System. Uniting daylighting with LEDs, it can save you up to 94% in energy costs. Featuring proprietary SunSense™ Technology, the system monitors daylight levels and allows the LEDs to activate automatically only when needed. The optional Occupancy Sensor makes the system even more energy efficient by preventing the LEDs from turning on unless an underlit area is occupied.

For the Solatube Brighten Up® Series, you can also get day and night lighting using one of our light kit options that can be wired to a wall switch.

Compact Fluorescent Light Add-On Kit

Add a dedicated compact fluorescent fixture to use with the Solatube Daylighting System as a recessed light fixture at night. Accepts one 26-watt compact fluorescent lamp (GX24q-3 Base, 26W 4-pin). Meets California Title 24 bath light requirements. Two fixtures may be used with the Solatube Daylighting System 290 DS.

Universal Light Add-On Kit with Medium Screw-in Base

Add on a light fixture to use the Solatube Daylighting Device as a recessed light fixture at night. The Solatube Daylighitng System 160 DS Light Add-On Kit accepts (1) Compact Fluorescent Lamp, Medium Base – 23 Watt Maximum, Total Maximum Length 4 3/4 in (120 mm). The Solatube 290 DS Light Add-On Kit accepts two Compact Fluorescent Lamps, Medium Base – 23 Watt Maximum, Total Maximum Length 4 3/4 in (120 mm).


On what roof types can Solatube Daylighting Systems be installed?

Solatube® Daylighting Systems can be installed on practically any roof type. We offer numerous roof mount options for both self-mounted and curb-mounted applications. For details, see our Product Selection Guides for residential and commercial applications.


What best practices can an installer employ to reduce the possibility of condensation when installing a Solatube Daylighting System?

Understanding the cause (e.g., poor ventilation) is the first step toward preventing condensation. Listed below are a number of steps that can be taken to reduce the potential for moisture buildup.

1. Always make sure round holes are cut in the roof deck, whether using the self-flashing or the curb-mounted cap. Square holes cut in the roof deck will let too much warm, moist air into the flashing or curb cavity.

2. Install a flashing insulator or curb insulator. These reduce the amount of warm air from the building’s interior that contacts the cold, metal interior of the flashing. On a curb-mounted unit, attach the curb insulator to the interior base of the curb, centering it over the round hole in the roof deck.

3. For self-flashing units, pack insulation material into the space between the flashing and the tubing to reduce the volume of warm, interior air that contacts the cold metal of the flashing. With curb-mounted units, push insulation into the curb cavity. Filling the curb cavity’s air space will equalize the temperature and reduce the occurrence of condensation. The Solatube® Curb Cap Insulation Kit is also recommended and provides R-6 rigid insulation at the underside of the curb cap. For the Solatube SkyVault® Series, rigid insulation is pre-installed in the roof assembly.

4. If a curb or flashing insulator is not used, another option is to seal the penetration where the tubing comes through the roof deck with an expanding foam sealant, insulation, or other similar product. This will reduce the chances of warm, moist air making contact with the interior of the flashing or curb cavity.

5. Ensure the dome is correctly attached to the flashing or curb cap, including dome seals in certain models. Solatube Daylighting Systems are designed to allow some air transfer from the interior of the system to the exterior. This allows moist air to vent, while enabling any droplets of water that may form on the dome to escape

6. In extreme cold climates, wrap the tubing in insulation. For best results, use foil-faced insulation. Be sure to insulate the entire tube run from the roof deck to the ceiling plane, leaving no gaps in the insulation. You can also use this method in extremely moist environments in an open ceiling application.

7. If a vapor barrier is present when penetrating the roof deck, ensure that it is maintained and sealed off once the Solatube Daylighting System has been installed.

For more details on how to address condensation, please contact your Solatube daylighting expert.


What happens if the dome gets covered with snow?

When just the roof is covered with snow, it may actually increase light output as the white snow makes the roof more reflective. When the dome itself is covered with snow, light output will be reduced but the dome will continue to perform. Tests have indicated that all Solatube® Daylighting System models can resist positive snow loads up to 150 pounds per square foot. For more information and to review the CCRR test report, click here.


What happens on a cloudy day?

Solatube® Daylighting Systems maximize the amount of daylight available for lighting your interior, regardless of sky conditions. Our proprietary Raybender® 3000 and LightTracker™ Technologies in our domes combined with our Spectralight® Infinity Tubing transfer the maximum amount of daylight from the rooftop down into the interior with minimal light loss, even on cloudy days. Keep in mind your light output is always relative to your light input. There will be a noticeable difference in light intensity between a clear, sunny day and a heavily overcast day. Our diffusers and Decorative Fixtures keep a consistent diffusion pattern, regardless of light intensity.


What happens on full moon nights?

The Solatube® Daylighting System captures ambient light so well that you can actually see a nice glow from your fixture on full-moon nights. If you prefer, you always have the option to add a Solatube Daylight Dimmer to block out unwanted light.


What if the light is too bright or bluish?

Solatube® Daylighting Systems are designed to control the intensity of daylight by rejecting overwhelming midday sun and reducing glare. They also reflect the true color temperature of the sky conditions outside.

For residential applications

We offer an array of Solatube Effect Lenses to adjust the light intensity and color. For homeowners who prefer less light intensity, the Softening Effect Lens creates a softer, glowing effect. The optional Solatube Daylight Dimmer can also be installed for easy adjustment of room light levels at the touch of a button. 
The Warm Effect Lens enhances natural daylight by “warming” it, creating a yellowish color similar to incandescent bulbs. Important: Never use standard window tinting or any flammable material to block the incoming light. This is a potential fire hazard.

To adjust both the light intensity and color, the Warm and Softening Effect Lenses may be used together to produce a glowing effect that mimics the color of incandescent lights.

For commercial applications

In our commercial line, we offer a secondary diffuser for the Solatube SolaMaster® Series that fits under the dome to soften the light. Our Solatube SolaMaster Series 330 DS dome maximizes midday sun while our Solatube SolaMaster Series 750 DS dome delivers consistent light output throughout the day. If using the Solatube Brighten Up® Series or Solatube Smart LED™ System, Effect Lenses may be used as described above.


What if the protective liner won’t come off the inside of the tubes?

If the tubes have been left in the sun or exposed to heat, the protective lining may adhere to the tubing and become difficult to remove. If this occurs, the tubing will likely need to be replaced. For best results, un-installed tubing should be kept in the packaging until it is installed. Also, it should not be stored in areas with direct sunlight or excessive heat for long periods of time.

What if there is no attic or plenum space?

Solatube® Daylighting Systems feature unique telescoping tubes that can be easily installed even when access to the attic or plenum is limited or there is no space between the ceiling and roof at all. We can also install most products in an open ceiling application where no ceiling exists and the underside of the roof deck is exposed.

One exception to this is the Solatube Smart LED™ System, which requires a minimum height of 16 in. (406 mm) between the base of the ceiling and the roof line. With the Solatube SolaMaster® Series 330 DS-C and 750 DS-C units, the transition box requires approximately a 12 in. (305 mm) depth between the ceiling and the roof.

We recommend you consult your local Solatube daylighting expert for specific details.


What is Color Temperature Maintenance and why is it important?

Color temperature Maintenance (CTM) is a measure of how well a system can deliver reflected light without a color shift. The specific measured L*a*b color model performance parameters associated with a reflective surface are used to determine the spectral consistency of light as it is transferred through a tubular system. A high CTM denotes a product that produces minimal color / spectral shift of the light, which makes it a highly desirable light source for interior illumination. The Spectralight® Infinity Tubing used in Solatube® Daylighting Systems has a high CTM, which allows it to deliver the brightest, purest daylighting without major shifts over the course of the day or changes in season.

What is Light Transfer Efficiency and why is it important?

Light Transfer Efficiency (LTE) measures how effectively and consistently daylight is transferred through a TDD’s optical tubing system and into a room for all daylight hours of the year. This factor is closely linked with the specular reflectance associated with a system’s tubing material. The higher the specular reflectance, the more efficient and consistent the transportation of light is. A high LTE typifies a product that limits light loss and, therefore, delivers an even and dependable amount of light to an interior, regardless of season or weather condition.


What is the approximate light coverage of a Solatube Daylighting System?

For Residential applications

The light coverage area varies among our Solatube® Daylighting System models. Keep in mind different light levels are required for different tasks. As a result, the approximate coverage areas are shown below for ambient light levels.

  • Solatube  Daylighting System 160 DS (10 in. / 250 mm) up to 200 sq. ft (19 sq. m)
  • Solatube  Daylighting System 290 DS (14 in. / 350 mm) up to 300 sq. ft (28 sq. m)
  • Solatube Smart LED™ System* (10 in. / 250 mm) – up to 250 sq. ft (23 sq. m)

These estimated lighting areas are based upon an average 6 ft (1.82 m) tube length and 8 ft (2.4 m) ceiling height with the dome in direct sunlight.

Light output will vary depending on the intensity of the sun. For example, there will be more natural daylight at midday than in the early morning or evening. Light output may also decrease as the tube length increases beyond the recommended distances.

*applies only to daylighting portion of the system


For Commercial applications

Please consult a Solatube Commercial Representative as acceptable illuminated areas will vary greatly due to ceiling heights and space uses. Our commercial experts are well-versed in application-specific Solatube design and light analysis for both new and retrofit projects.


What is the product warranty?

Under the product warranty, Solatube® Daylighting System components are covered for 10 years, most electrical components for 5 years, and Solatube Smart LED™ electrical components for 3 years. For full warranty details, click here.


What is the ultraviolet (UV) and infrared (IR) impact of installing a Solatube Daylighting System?

To answer this question, we first need to understand what wavelengths of radiation are emitted through a Solatube® Daylighting System. Solatube Daylighting Systems utilize two technologies to eliminate ultraviolet (UV) radiation and reduce heat from infrared (IR) wavelengths entering the building interior.

The first technology is related to the domes. Solatube acrylic outer domes have special UV inhibitors designed to block 100% of UVB (280 to 315 nanometers), 100% UVC (100 to 280 nanometers) and 98.5% UVA (315 to 400 nanometers) rays.

The second technology is related to the tubing. Spectralight® Infinity Tubing transmits the visible spectrum of light (400 to 760 nanometers).  A minimal amount of the infrared spectrum of light (above 760 nanometers) is transmitted by the Spectralight Infinity Tubing.

With this information in mind, the following subjects can be addressed.

Plant Growth

In conjunction with the above information, there are a few factors to consider when determining if a Solatube Daylighting System will have an effect on plant growth. The first factor is how much UV, if any, the particular plant will need for proper growth. Second, the size of the daylighting system used may impact how much light the plant can obtain. It is also important to point out that the Solatube Daylighting System removes a majority of the infrared wavelengths, which substantially reduces any heat-related stress problems that may occur with indoor plants.

Typically plant growth occurs between 400 and 1000 nanometers. Based on this data, it would be safe to say that, in general, a Solatube Daylighting System will have a positive effect on plant growth depending on a particular plant’s UV requirements.

Solar Heat Gain

With the infrared-blocking capabilities of the Spectralight Infinity Tubing, removing greater than 50% of the heat from the IR wavelengths (>900 nanometers) of the sun with every reflection on the tube surface, the Solar Heat Gain of Solatube products is greatly reduced. This, in turn, will reduce the air conditioning load requirement for the space being daylit. These technologies allow Solatube Daylighting Systems to provide the highest light output performance with minimal thermal impact.

UV Effect on Skin and Vitamin D Production

The different UV wavelengths affect skin in the following ways.

UVA – The lowest energy range, UVA causes little burning ordinarily, but it penetrates deeply, beyond the surface layer of the skin. Over long periods of exposure, UVA causes wrinkling and premature aging of the skin.

UVB – More energetic, the chief burning and tanning rays which area major factor in producing skin cancer, although not penetrating beyond the skin.

UVC – The most energetic, intensely burning rays.  Fortunately, UVC is mostly absorbed by the ozone layer, which essentially serves as “sunscreen” for the Earth.

Vitamin D production occurs when a compound within the skin reacts with UV rays between the 270-300 nanometers wavelengths, with peak synthesis between 295-297 nanometers. Based on this information the Solatube Daylighting Systems do not transfer the required UV for Vitamin D synthesis because it will block all of the UVB and UVC rays, which fall between the 100-315 nanometer range.

Note: The UV information in this article is specific to Solatube Daylighting Systems. Other TDD products may not provide the same performance standards.


When roofing, what is the best time to install a Solatube Daylighting System?

All Solatube® products were designed with retrofit applications in mind. However, when dealing with a new roof installation or a re-roofing project, it’s recommended to coordinate with the roofer.

For residential applications

For typical shingle roofs, it is best to install after the new roof is in place. However, the Solatube Daylighting System can easily be installed at the same time the roof is going on in most cases.

When installing a Solatube Daylighting System on a tile roof, installation is usually done after the roof is completed. On hot mop applications, installation can be done during or after.

For commercial applications

For new construction or re-roofing projects, our Solatube daylighting experts often coordinate the installation of a Solatube Daylighting System with a professional roofer to ensure flashings or curbs are properly installed. This helps to maintain the roof warranty, if applicable. Since they are factory-trained on all Solatube products and experienced with installing on a wide variety of roof types, Solatube daylighting experts can provide valuable information on how to ensure a successful outcome.


Where can Solatube Daylighting Systems be installed?

The better question is where can’t they be installed? Solatube® Daylighting Systems have been installed in virtually every type of residential and commercial application. See our residential and commercial showcases for examples.


Why is Specular Reflectance a better measurement of light output than Total Reflectance?

The reflection of light is extremely predictable. When light strikes a surface, it is either absorbed or reflected. Total reflectance indicates the percentage of light that is reflected, regardless of the direction it travels after leaving the surface. A surface’s total reflectance can consist of both specular and diffuse components. To illustrate this, imagine a ray of light as a tight bundle of smaller, individual rays, all traveling parallel to each other. In accordance with the Law of Reflection, rays that strike a smooth surface will reflect and remain in a concentrated bundle. This is called specular reflection and represents a “mirror-like” reflection of light. On the other hand, rays that strike a rough, or diffuse, surface will reflect and scatter in many directions through diffuse reflection.

While a diffuse surface can have a high total reflectance, the reflected light is scattered, which prevents it from being transmitted in a consistent and tightly-controlled fashion. For tubular daylighting devices (TDDs), a high specular reflectance is imperative so that light can be efficiently transferred through the system. A tubing system with a diffuse reflectance component should be avoided since that would result in light being scattered and lost back out through the top of the system.

The Spectralight® Infinity Tubing used in Solatube® Daylighting Systems is the most reflective material used in TDDs. With an extremely high specular reflectance of up to 99.7%* over the visible portion (ranging between 380-760 nanometers (nm)) of the electromagnet spectrum, it ensures that very little light is lost as it travels through the optical tubing system.

Achieving a high specular reflectance is critical since even small differences in reflectance values can significantly impact light output. That’s because every time a ray of light is reflected, some amount of that light is either scattered or lost through absorption. The difference of just a few percentage points in specular reflectivity makes a huge difference in overall performance.

Contrary to total reflectance, specular reflectance is a key factor in determining an optical tube’s efficiency in transferring light, and manufacturers should provide specular reflectance data to document the true efficiency of their TDD systems.

*Specular reflectance greater than 99%, with wavelength-specific reflectances up to 99.7% for the visible spectrum


Will a Solatube Daylighting System work for a mobile or manufactured home?

Yes, dim interiors are common with mobile homes because carports and patio covers often shade the windows. Solatube® Daylighting Systems overcome this issue by delivering light directly into the interior through the roof. Plus, installation is quick and easy because no structural modifications are required.


Will a Solatube Daylighting System work in cold climates and northern latitudes?

Our products feature dome optics that help collect low-angle sunlight, which is extremely important in northern latitudes. As a result, Solatube® Daylighting Systems have performed successfully in cold weather climates like the Northern U.S.A., Canada, and Northern Europe for more than 20 years.

Will a Solatube Daylighting System work in hot climates like Arizona?

Yes, Solatube® Daylighting Systems work especially well in hot climates. All of our Daylighting Systems feature Spectralight® Infinity Tubing. This transmits the visible spectrum of light (400 to 760 nanometers), but provides significant blockage of infrared wavelengths greater than 900 nm, which is the main culprit in solar heat gain.

Additionally, the dome ring in the Solatube 160 DS/ISn and Solatube 290 DS/ISn acts as a thermal break between the flashing and tubing to prevent external heat from entering an interior space. In the Solatube SolaMaster® Series, the tube ring performs this same function. In the Solatube SkyVault® Series, R-6 rigid insulation that comes pre-installed in the curb cap roof assembly prevents heat transfer. All of our other curb-mounted units have the option of adding the Curb Cap Insulation Kit for maximum heat transfer prevention.

Also, the Raybender® 3000 Technology featured in many of our products helps to reject overwhelming light and heat when the sun’s rays are most intense.
The Solatube Brighten Up®, SolaMaster 750 and the SkyVault M74 also offer inner dome options that improve thermal performance by creating a dual dome system.
These technologies allow Solatube Daylighting Systems to provide the highest light output performance with minimal thermal impact.


Will a Solatube Daylighting System work when installed on the north side of a roof?

A Solatube® Daylighting System works well on the north side of a roof. However, it performs even better when exposed to direct sunlight. For the best results, position the system where it will receive the most direct south-facing sunlight possible. To catch more direct rays, a turret extension can also be added to raise the dome height above the roof peak if on the north side of the roof.

The reverse is true in the southern hemisphere. There, a north-facing position is ideal.


Will a Solatube Daylighting System work with a Solatube Light and Ventilation Add-On Kit at the same time?

Yes. The Solatube® Light and Ventilation Kits can be added to the Solatube Daylighting System 160 DS model to create a dynamic 3-in-1 fixture that includes daylighting, night lighting and venting functions in one ceiling location.


Will I have to cut the tubing?

Most Solatube® Daylighting System extension tube sections have a special notching system that allows one end of the tube to be larger than the other so they can telescope into each other for easy installation. As a result, trimming is rarely necessary.

The exception to this rule is the Solatube SkyVault® Series, a product that was designed for commercial high bay, open ceiling applications that don’t require connecting to a ceiling.

It features an innovative Tab-Lock Connection System with Tube Belts as well as extension tubes that come in pre-determined lengths, which makes cutting the tubing unnecessary.


Can the dome be raised higher above the roof?

All flashings or curb caps can be modified by adding a turret extension. It raises the height of the dome to avoid snow, rain runoff, and shading from roof obstructions like mechanical units or parapet walls. The turret extension also allows the dome to clear thick roofing materials or insulation.Turret extensions are available in 2 in. (50 mm), 4 in. (100 mm), 12 in. (300 mm), 24 in. (600 mm), 36 in. (900 mm) and 48 in. (1,200 mm) heights. See Product Selection Guide for specifics.

Keep in mind a turret extension must still be lined with Spectralight® Infinity Tubing. In the case of Solatube® Daylighting Systems 160 DS and 290 DS models, addition of a turret extension may require a Spectralight Infinity 0-90 degree angle adapter.


How are the extension tube sections fastened together?

Most Solatube® Daylighting Systems feature tubing with a specially designed notching system that allows one tube to telescope into the next, so they rarely have to be cut to length. High-quality foil tape is used to seal all tubing seams. This keeps bugs and dust from entering the system, ensuring maintenance-free operation. Tube sections are further reinforced by fastening them with provided self-tapping screws for structural integrity.

One exception is the Solatube SkyVault® Series, which features a patented Tab-Lock Connection System that guarantees proper assembly. Additionally, Tube Belts ensure structural integrity by cinching the tube connection to prevent gaps and provide a tapeless, self-sealing joint. This combination of features simplifies installation and reduces labor costs.


What is Spectralight Infinity and how does it achieve maximum Light Transfer Efficiency without shifting colors?

Used in both our LightTracker™ Reflector and our tubing, Spectralight® Infinity is a proprietary material that has a specular reflectivity of 99.7%*, the highest of any material used in tubular daylighting devices on the market today. As a result, less than 1% of the daylight captured is lost with each “bounce” of daylight down the tube. This becomes increasingly important when light levels are low, such as in the early morning or late afternoon, on overcast days, or during winter months. At these times, the reflected daylight may make hundreds of bounces down the tubing. Because Spectralight Infinity has such a high Light Transfer Efficiency (LTE), daylight can be transmitted over long distances with minimal light loss to provide consistent illumination, regardless of season or weather condition.

In other systems that use tubes with lower reflectivity, so much light is lost (some as high as 16% with each bounce!) that little usable light remains by the time it travels all the way down the tube.

In addition, Spectralight Infinity Tubing also has a high Color Temperature Maintenance (CTM), which means it delivers the true color of the daylight with no color shift. Other tubing materials are not only less effective at reflecting light but are not “spectrally-neutral,” meaning that they can shift the color of the light significantly.

The end result is that you get maximum light output with no significant color shift for the brightest, cleanest natural light possible.

*Specular reflectance greater than 99%, with wavelength-specific reflectances up to 99.7% for the visible spectrum


What length can the tube be?

To achieve optimal light output in spaces that require long tube runs, we recommend using tube lengths no longer than those listed below:

  • Solatube® Brighten Up® Series: Solatube 160 DS (10 in. / 250 mm) – 20 ft (6m)
  • Solatube Brighten Up Series: Solatube 290 DS (14 in. / 350 mm) – 30 ft (9m)
  • Solatube Smart LED™ System: (10 in. / 250 mm) – 20 ft (6m)
  • Solatube SolaMaster® Series: Solatube 330 DS and 750 DS (21 in. / 530 mm) – 50 ft (15m)
  • Solatube SkyVault® Series: M74 DS (29 in. / 740 mm) – 100 ft (30m)

For tube runs exceeding 15 ft in length or running horizontally, we recommend the addition of suspension wires for support.

In short tube runs, there is no minimum length for the Solatube Brighten Up Series. The tubing may simply need to be modified to fit the space. This can be done easily by telescoping or cutting the tubing to the desired length. With the Smart LED System, the minimum length is 16 in. to accommodate the Amplifier. For SolaMaster 330 DS-C or 750 DS-C, a minimum depth of 12 in. is required to accommodate the transition box. For most open ceiling applications, the tube can be cut or telescoped to make the diffuser flush with the underside of the roof deck or to lower the diffuser to the desired height.

For Solatube SkyVault M74 DS applications, the Tab-Lock Connection System dictates that the tubes are set to designated lengths. Curb height can be manipulated to affect diffuser position.

Keep in mind that, for a short tube run, creating tube angles may not be possible.