7 Expert tips for installing recessed lights at home
What's Recessed Light ?
When planning for recessed lighting in space, people often encounter questions such as “What should I pay attention to when replacing old recessed lights?”, “For recessed lights with adjustable angles, how far should the center of the opening be from the wall?”, “How do I create ambience with recessed lights?”, “What kinds of recessed lights are available?”, “Besides 15cm open recessed lights, are there any other options?”, and “How can I waterproof recessed lights in places prone to dampness such as bathrooms and balconies?”. Here, we at Lightinology share some knowledge on recessed lighting design with you.
Introduction (1): What is a recessed light (can light)? A recessed light is a light fixture that must be installed into a round or square opening in the ceiling. In most cases, it is down lighting (downward-facing lighting). Recessed lights can generally be divided into two types: Fixed recessed lights, and adjustable angle recessed lights.
Introduction (2): The main function of recessed lights is not only to provide basic lighting in a space, but also to create a flush, clean appearance for the ceiling. Using different types of recessed lights in a space can create spatial layering and avoid monotony in the space. It can enhance the ambience of indoor spaces, help people stay in a good mood over a time period, and reduce tension and stress.
Introduction (3): Experts suggest avoiding traditional methods of purchasing light fixtures when buying recessed lights. Do not select only on the basis of wattage. In addition to wattage (power consumption) considerations, take into account color temperature, color rendition, optical design, and the profile and dimensions of the light fixtures.
Introduction (4): When purchasing recessed lights, consumers should match the recessed light fixture type to the different ceiling height, desired ambience for the space, furniture, décor, and functions of the space; don’t just opt for a single type of recessed light for all the spaces.
Introduction (5): Many customers ask about the color of light that should be used in a space, and whether to opt for yellow light or natural light. For these kinds of questions, we recommend the following article: What is color temperature?
Tip 1. First confirm light fixture height and ceiling depth.
First, confirm whether the depth of the wood ceiling can accommodate the recessed lights you wish to install. If you wish to install non-flat recessed lights or high-wattage recessed lights, Lightinology recommends that you reserve more space for heat dissipation. Otherwise, even the body of LED lights can break down easily or become dimmer due to the accumulation of heat.
For example, if the total height of the light fixture is 10 cm, the depth inside the ceiling should be at least 13 cm to be deep enough for installing the recessed light. In addition, in some commercial spaces, in-ceiling conduits and plumbing are complex, and contain fire suppression piping and air-conditioning ductwork. Therefore, during installation, special attention must be paid to whether there is sufficient space for heat dissipation, or if leaking water could drip onto the light fixtures.
Tip 2. How to measure the dimensions of an opening when replacing old recessed lights with new fixtures
The dimensions of recessed lights generally refer to the dimension of the opening that can accommodate the installation of the recessed lighting. Currently, the common market dimensions for recessed lights are 7cm, 7.5cm, 8cm, 8.5cm, 9cm, 10cm, 12cm, and 15cm.
Installation of new recessed lights in new construction: If installing recessed lights in a new renovation, consumers should refer to the ceiling opening dimensions recommended for each type of recessed lights, and provide them to their renovator or designer as reference for on-site construction. Current LED technology is developing rapidly. If you’re using light fixtures that require small openings, we recommend avoiding numerous large opening recessed lights all over the ceiling, as these will affect the visual space. Some recessed lights today have fine edges to create the visual effect of borderless recessed lights. With these fixtures, renovators must be extra precise when cutting the holes. Before the openings are cut, consumers should also buy a set of samples as a reference for the on-site designer or renovator.
Replacing old recessed light with new recessed lights: It is very important to first confirm the dimensions of the old recessed light's opening. To confirm the dimensions of the old recessed light’s opening, measurement cannot be merely taken from the outside. Remove the old recessed light and measure the dimensions of the opening in the ceiling. Next, check whether the dimensions of the new recessed light fixture will fit the dimensions of the original opening. If not, the new fixture will not fit into the old recessed light’s opening (we recommend that the above tasks be performed by a licensed electrician).
Tip 3. When to use fixed versus adjustable angle recessed light
Fixed recessed lights should be selected for long corridors, open spaces, and fixed furnishings or equipment. The advantage is that if the lights must be repaired or replaced, the light distribution can be kept consistent; the original settings will not change when different people do the maintenance or replacement.
Adjustable angle recessed lights should be selected for walls that have artworks, décor, accent painting, or non-fixed furnishings (sofa/dining table/mattress, etc.) under the ceiling. This provides more flexibility in matching the space and lighting, so that future lighting can be adjusted to match changes in the décor and furniture.
Tip 4. How to create bright and comfortable lighting in a space
To create an interior space that is bright, comfortable, and uniform, and achieve similar lighting box effects found in an Apple Store or other technology companies, many lighting design techniques can be employed, such as using light shelves on ceilings, indirect lighting, and wall wash lights. Consumers who choose to use recessed lights should be particular about selecting lights with a wide light projection area (angle), so that the light extends from the top to the bottom and creates a light box effect. The words for “light projection area (angle)” here is means "field angle”of a lighting fixture, and does not refer to the size of the beam angle. If a light has a small beam angle but the field angle is wide, it can also create a bright and uniform lighting effect.
Tip 5. How to create a warm and intimate lighting ambience in a space
To create the intimate and high-end lighting effect found in star-rated hotels, high-end restaurants, and cozy bars, the first key is to refrain from an excessive number of lights. Second, select recessed lights with a small field angle or fixture with anti-glare fittings to reduce the proportion of light spreading to the upper half of the space as it extends down. The beam angle of the light should not be too large. Generally, a beam angle of 10-20 degrees or 20-40 degrees is recommended. If there are no special requirements for general surfaces or facades, the choice of color temperature should be 2700K-3000K for a cozy and relaxing tone. A natural light color temperature of 4000K should be used to create a modern style.
Tip 6. IP44 level waterproof recessed lights are recommended for bathroom spaces
Most indoor lights are IP20 level, where the "2" means a dustproof ability able to prevent entry of foreign bodies larger than 12.5mm in diameter into the lights; and "0" means no waterproof or protection ability.
An IP43 level or above is recommended for bathrooms and semi-outdoor areas (such as balconies). Most common bathroom lights have a maximum of IP44. The first "4" represents the ability to prevent/block entry of foreign bodies greater than 1mm in diameter; dustproof ability higher than "2” means they are many times more protective. The second "4" means that the light fixture is protected against splashing water, and has a flow rate of 10 liters per minute, a flow pressure of 80–100KN/m2, a waterproof protection of 5 minutes against water splashing from within 60 degrees, and can pass a waterproof test from all splash angles.
The leak-proofness of IP44 lights is much better than that of IP20 lights; this means that the airflow and heat dissipation inside the lights are lower than those rated IP20. Therefore, more LED heat dissipation issues must be considered in designs using these lights. The LED heat dissipation modules must be bigger, and the LED specifications must have greater heat-resistance and lower lumen depreciation than general LEDs.
Tip 7. How far should the center of the opening be from the wall for adjustable angle recessed light?
How far should the center of the opening be from the wall for adjustable angle recessed lights? This is a frequently asked question. Generally, for wall washing, the recommended center of the opening for the light is at most 40-50 cm. To illuminate a specific position on the wall, the distance from the wall must be determined according to the conditions of the site, which is a mathematical problem. Consumers should refer to the diagram above and the formula description below for further information.
We assume that the setback distance of the fixture from the wall is SD, and assume that the visual height (Eye Height) calculated from the ceiling of the scene is EY.
So according to the definition of trigonometric functions :
tan(θ) = sin(θ) / cos(θ) = SD / EY
Therefore, the distance between the lamp and the wall can be obtained by this formula :
SD = EY x tan(θ)
Generally, the adjustable angle of a recessed downlight is about 30 degrees, so :
tan(30)= 0.57735 ≈ 0.6
Finally, we can get a mathematical formula that is :
SD = EY x 0.6
Let's take this example: The wood ceiling in your home is at a height of 270 cm; a piece of art is installed on the wall; your visual height is 160 cm. The EY value is therefore 110 cm. The recommended distance between the recessed light and the wall is then 110 × 0.6 = 66 cm.
If the recessed light is mainly for wall washing, and there is no artwork, then the position of the light will be higher than the visual height. That's because this way, the space will have an additional feeling of height. Based on your desired light projection on the wall, apply the above formula. For example, if the wood ceiling in your home is at a height of 270 cm, and the desired height of your light projection is 200cm, then the EY value is 70cm. The recommended distance between the recessed light and the wall is then 70 × 0.6 = 42 cm.